Gardening does not end with the first frost! We will work our way from clearing the least hardy crops to those we can leave outside all winter. See our tableWinter Kill Temperatures of Cold-Hardy Vegetables. We will harvest or cover all the frost-tender crops, make a last harvest of rhubarb (the stems are hardy to 22°F (-6°C)) and hoop and rowcover the last outdoor lettuce. Our June-planted potatoes will be our last big harvest for the year.
We pull up the biggest Purple Top turnips and Cylindra beets, leaving the others a bit more room to size up before their killing temperature of 12°F (-11°C). Any day now, we’ll start harvesting fall leeks (King Richard and Lincoln), keeping the winter-hardy ones (Tadorna) for the winter.
I recommend learning your local weather patternsby keeping records and watching what happens. Here’s what I’ve learned about ours:
Our mid-Atlantic climate is controlled by three weather systems,
mainly by moisture from the Gulf of Mexico,
the Bermuda High Pressure area in summer,
and recurrent waves of cold Canadian air in winter.
Rain (statistically fairly evenly distributed throughout the year in our county) has slight peaks in January, February and March, and again in early June and August.
Some parts of our area can experience long periods of drought. September-November is the drier season but it’s also the hurricane season, so the net result is very variable.
We use Wunderground.combut subtract 5F° from their forecast night lows for our nearest town, and mentally downgrade the chance of rain by 10%, as rain often passes us by as it scoots along the river valley north of us.
Our average first frost date is October 14. Actually from our own records it has averaged 10/20 (13 years of our own records). So it’s time to start thinking about frost. It’s good to be prepared.
According to Dave’s Garden in Louisa County where I live, the threshold of 36°F (2°C) has a 50% likelihood on Oct 3; the 32°F (0°C) threshold has a 50% likelihood by Oct 13 and the 28°F (-2°C) threshold is as likely as unlikely by Oct 27. The 90% chances occur by Oct 14, Oct 28 and Nov 12 respectively.
Now that climate change is here, it pays to be ready for weather different from what we have experienced previously. Keeping records helps, as does having good thermometers for air and soil.
Four Ranges of Cold-Hardy Crops for Harvest at Various Stages of Winter
This simple model helps reduce confusion and set priorities
1. Crops to harvest before cold fall weather (32°-25°F) and store indoors:
Chicory for chicons or heads; crosnes/Chinese artichokes, dry beans, Chinese cabbage, peanuts, “White” Peruvian potatoes at 32°F (0°C) approximately, pumpkins, seed crops, sweet potatoes at 50°F (10°C), winter squash.
2. Crops to keep alive in the ground into winter to 22°-15°F (-6°C to -9°C), then harvest.
Store: Beets before 15-20°F (-9.5 to -7°C), cabbage, carrots before 12° F (-11°C), celeriac before 20°F (-7°C), kohlrabi before 15°F (-9.5°C), winter radish including daikon before 20°F (-7°C), rutabagas, turnips before 20°F (-7°C).
Use soon: Asian greens, broccoli, cabbage, chard, lettuce, radishes
3. Hardy crops to store in the ground and harvest during the winter.
In zone 7, such crops need to be hardy to 0°-10°F (-17.8°C to -12.3°C):Collards, horseradish, Jerusalem artichokes, kale, leeks, parsnips, scallions, spinach.
4. Overwinter crops for spring harvests before the main season.
In zone 7, they need to be hardy to 0°-10°F (-17.8°C to -12.3°C): Cabbage, carrots, chard, collards, garlic and garlic scallions, kale, multiplier onions (potato onions), scallions, spinach.
Frost is more likely at Twin Oaks if:
The date is after 10/14 (or before 4/30).
The daytime high temperature was less than 70°F (21°C).
The sky is clear.
The temperature at sunset is less than 50°F (10°C).
The dew point forecast is low, close to freezing. Frost is unlikely if the dew point is 43°F or more.
The Wunderground 3.30pm forecast low for Louisa Northside is 37°F (3°C) or less.
The soil is dry and cool.
The moon is full or new.
There is little or no breeze, although if temperatures are falling fast, the wind is from NW and the sky is clear, then polar air may be moving in, and we’ll get a hard freeze.
Frost Alert Card
For just this time of year, we keep a Frost Alert Card reminding us which crops to pay attention to if a frost threatens. We check the forecast online at 3.30 pm (we find that’s late enough to be fairly accurate about night temperatures and early enough to give us time to get vulnerable crops covered).
The big decision is the triage of harvest/cover/let go. Our list is not just crops that will die with the first frost but also ones that will soon need covering as temperatures decrease.
Cover lettuce, zucchini, summer squash, cucumbers, beans, Chinese cabbage, pak choy, lettuce and celery.
Harvest crops listed above that can’t or won’t be covered.
Harvest all ripe tomatoes, eggplant, corn, limas, cowpeas, okra, melons.
Harvest peppers facing the open sky, regardless of color. (Often only the top of the plant will get frosted).
Check winter squash and harvest any very exposed squash.
Set up sprinklers for the night, on tomatoes, peppers and a cluster of beds with high value crops.
We really like this pepper strategy we have developed: by picking just the peppers exposed to the sky, we reduce the immediate workload (and the immediate pile up of peppers in the cooler!) and we often get a couple of milder weeks after the first frost before the next. By then the top layer of leaves that got frosted the first time will have died and a whole new layer of peppers will be exposed and need harvesting. This way we get fewer peppers at once, and a higher percentage of ripe peppers, which have so much more flavor.
Our overhead sprinkler strategy is useful if a frost is coming early when we still have many tomatoes we’d like to vine-ripen. Keep the sprinkler running until the sun is shining on the plant sin the morning, or the sir temperature is above freezing again. The constant supply of water during the night does two things. First water gives off heat as it freezes. Yes, really. It’s easier to understand ice taking in heat to melt, but the flip side is that water gives off heat as it freezes. This latent heat of freezing helps warm the crops. And if ice does form, the shell of ice around the plants stops more cold damage happening.
Frost Alert List
Harvest all edible
Harvest all edible
Harvest all edible
Harvest all edible
Including green ones
Harvest all edible
Peppers exposed to the sky
Harvest all edible
West Indian gherkins
Harvest all edible
Harvest all edible
Harvest all edible
Beans #4, 5, 6, then cover
Uncover once mild again
Thick row cover
Spring hoops or none. Ditto
Thick row cover
Spring hoops or none. Ditto
Thick row cover
Double hoops – leave covered
Thick row cover
Last lettuce bed
Double hoops – leave covered
Overnight from before 32F till after sun shines on plants
Roma paste tomatoes and peppers
Other vulnerable raised bed crops
Cold Weather Crop Protection
Rowcover – thick 1.25 oz rowcover gives about 6F (3.3C) degrees of frost protection. Use hoops.
Low tunnels and Quick Hoops are wider version of using rowcover. They need the edges weighting down. Best for climates where the crops are being stored in the ground until spring, when they start growing again. Less useful in climates like ours which have very variable winter temperatures, and are warm enough that we realistically expect to harvest during the winter, not just before and after.
Caterpillar tunnels – 2 beds plus 1 path, tall enough to walk in. Rope holds cover in place, no sandbags.
High tunnels (= hoophouses), single or double layer. Double layer gives 8F (4.5C) degrees of protection, plus plants can survive 14F/8C colder than they can outside, without extra rowcover; at least21F/12C colder than outside with thick rowcover. Leafy crops are not weather-beaten. We strongly believe in two layers of plastic and no inner tunnels (rowcovers) unless the night will be 8°F (-13°C) or colder outdoors.
Salad greens in a hoophouse in zone 7 can survive nights with outdoor lows of 14°F (-10°C). A test year: Lettuce, Mizuna, Turnips, Russian kales, Senposai, Tyee spinach, Tatsoi, Yukina Savoy survived a hoophouse temperature of 10.4°F (-12°C) without rowcover, -2.2°F (-19°C) with. Brite Lights chard got frozen leaf stems.
The Remarkable Things that Insects (and Other Invertebrates) Do – And Why We Need to Love Them More
Chelsea Green Publishing, September 2021, 224 pages, $17.95
Vicki Hird has a passion for insects, and this book brings home to us how much depends on the well-being of invertebrates in the world. Insects are a cornerstone in our ecosystem, and we must reverse the current dangerous decline in bug populations (40% of insect species are at risk of extinction and 33% more are endangered). We are heading towards “Insectageddon.” After reading this book, I found myself being much more careful about gathering up insects inside the house and taking them outside, where I imagine they will thrive better. Did you know that spiders rest calmly in your gently closed hand? They do not wriggle and tickle!
We need to overcome any aversion or indifference to creepy-crawlies, and change our attitudes to respect, appreciation, and some humility if possible. Insects pollinate plants, recycle waste into nutrients, control pest species, add air channels in the soil, and ultimately return themselves to the soil food web.
Vicki explains how to rebug our city green spaces, grow gardens without pesticides and weedkiller, teach children to appreciate small creatures, make choices that support insect-friendly (planet-friendly) production of food and fiber, and make wider choices that affirm human dignity and equal rights.
This book has charming insect drawings, and delightful anecdotes: “I was never going to get the pony I wanted, so I settled for an ant farm at an early age.” Studying biology at school led Vicki to a summer job observing bees at a research station. A later job investigating cockroaches led her to respect them and realize that it is humans that need better control, more than roaches do.
Vicki has been an environmental campaigner, lobbyist and researcher for about 30 years, and is the mother of two children. Vicki is also head of the Sustainable Farming Campaign for Sustain: The Alliance for Better Food and Farming, a UK alliance of organizations and communities advocating for healthy food, people and environment, and equity in society. She has a website for Rebugging.
Those over 50 (and maybe 40) will have noticed that long car drives no longer lead to cars covered in smashed bugs. There are fewer butterflies. More than twice as many insect species as vertebrate species are at risk of extinction. I noticed on a trip to England after an absence of a couple of years, that the number of sparrows has plummeted. We are more likely to get distressed about the charismatic mega-fauna, but less so about formerly ubiquitous sparrows, and even less about insects. There may be 4 million unidentified species of insects (as well as the million we know). In the UK 23 bee and wasp species have become extinct since 1850.
So, what is ‘rebugging’? It is a form of rewilding (the introduction of similar-to-natural ecosystems and missing species into an area and then waiting to see if the species can settle in). It is somewhat controversial, and alone is insufficient to cause all the changes we seek. We also need changes in policy, lifestyle, and civic involvement. This book provides information, encouragement and tools to act.
What would the world be like without bugs? “A great image that has been doing the rounds is a picture of a bee saying, “If we die, we’re taking you with us.” It’s not an empty threat, but a fact – we would not last long without insects. Our flowering plants would die off; all the species that dine on insects would be lost, followed by the next ones up the chain; dead animals would pile up undigested; trees would cease growing in the compacted airless soil.
But this is not our inevitable future. We can step back, as we have done when the dangers of DDT, CFCs, and nuclear weapons became blindingly clear. We can work to restore habitat, reduce damage and make political and economic structural changes at all levels in society. We can start by “rebugging our attitudes.”
How can we protect and nurture invertebrates? We can help research what’s out there. We can encourage others to be concerned and take action to protect invertebrates. We can teach others about the value of insects for human well-being. We can make havens for wildlife, convert every city street into a biocorridor, share designs for pollinator-friendly gardens, encourage conservation of water and other natural resources, make urban farms and community gardens.
The book is studded with sidebars on aspects of the value of insects, such as “How much is a bee worth?” (The answer is over $3,000 per hectare in pollination services, for wild bees) That’s more than 651 million GBP to the British economy.
Insects are food for many animals such as poultry, fish and pigs. And some insects could be food for humans. I ate a 17-year cicada last time they were in our area (2013). I was partly inspired by Jackson Landers’ book Eating Aliens. And really, if you can eat shrimp, you can eat meaty insects. But Rebugging isn’t mostly about eating insects, but rather preserving their lives, and benefiting from their contributions.
If you are still unsure what bugs do for us, the second chapter spells it out. We would be knee-deep in manure, leaf litter and dead animals within weeks, if there were no bugs eating it all, and enriching the soil. Tardigrades (water bears or moss piglets) are the most resilient animals known, able to survive extreme temperatures, pressures, dehydration, oxygen deprivation, starvation and radiation. They can remain in suspended animation for years until conditions improve. They have already survived all five mass extinction events, and some have been revived from a hundred-year-old sample of moss in a museum. Respect, please!
Avoid spraying wasps with pesticides-in-a-spray-can. They are as useful as bees and ladybugs, and are the best pest control we have for hauling away cabbage caterpillars. If you are more motivated to provide accommodation for ladybugs than wasps, keep moist dark places like old hollow stems, bark pieces and logs where the adults can overwinter. I could really use some early-spring-wakening ladybugs in our hoophouse to tackle the aphids!
Carefully introduced biological bug control can reduce the amount of pesticides used. A scientific risk assessment is an important first step, though. The 1930’s introduction of cane toads in Australia for pest control was a terrible mistake. The toad was a worse pest than the bugs had been. There are many more success stories than disasters!
Rewilding can be complicated – looking at a huge overgrowth of creeping thistle is alarming. Happily, the biggest migration of painted lady butterflies came over and laid eggs on the thistles. The resulting spiny black caterpillars ate the thistles down to the ground. UK organizations have been creating maps of “insect superhighways” they are calling B-Lines, that will be filled with wildflowers so that insects and other wildlife have continuous corridors to travel from one area to another. There’s a two-page spread of possible actions to help the rebugging process, starting with publicity and education, and moving onto helping build bug-friendly habitat in public places and workplaces and private gardens.
Green public spaces can include a wide variety of invertebrate species. Look on derelict land, in cemeteries, along grass verges, and even on golf courses. Many companies and local authorities are now wanting to manage their land in ways that support more wildlife, and with encouragement might move another step in that direction. Tiny public orchards and forests are being planted in some places. There is a sidebar of actions to reduce deliberate, accidental, and thoughtless damage to insects.
After starting small and local, you might be ready to expand your ambitions and commitment. The overall total mass of insects is estimated to be falling by 2.5% every year. One big factor pushing species towards disaster is climate change. This is a big one to tackle, and yet we must. Overwintering numbers of monarch butterflies (the celebrities of the insect world) have dropped to less than 1% of their 1980’s population. Yes, compared with 40 years ago, the population is now just 1/100 of what it was. When food species arrive, peak, or leave earlier in the year due to changed temperatures, the predator species goes undernourished. Pesticide contamination gets a lot of blame too.
Water pollution also harms diversity. Leached fertilizers in estuaries have created ocean dead zones. Combating climate change might not be what you expected to read about when picking up a book on rebugging the planet, but it is vitally connected. We can learn from bugs about climate management. Honeybees have learned how to mob an invading Asian giant hornet and cook it to death. In Brazil, scientists discovered an area of 200 million termite mounds each spaced 60 feet from its neighbors. This is all one colony, connected underground. Some of the mounds are over 4,000 years old. They have created a stable environment for millennia. The methods of ventilation and gas exchange could be copied for human habitation.
Are 5G phones heating insects 370% above normal levels and cooking them in the electromagnetic fields they generate? It could be true, based on research on models. The action list at the end of this chapter urges us to avoid 5G phones if we can, and not to use them outdoors if we must have one.
The chapter on why our farming, food and shopping all need bugs opens with a discussion on almond milk. The “dark reality” is that huge almond plantations need millions of bees brought in every year for pollination. Thousands of colonies are moved in to California’s Central Valley, for example. 30% of these bees die, because the environment is hostile, devoid of crops other than almond trees. Local wildlife cannot survive either.
It is a mistake to think that all vegan milk-substitutes are environmentally better than all dairy milk. It takes roughly 4 gallons of water for every gallon of milk a cow produces. Almond milk is much more intensive on water use: it can take up to 101 gallons of water to grow 1 cup of almonds, plus another 3 or 4 cups of water to manufacture almond milk. In fact, many commercial almond milks only have about 2% of almonds in them – the rest is water!
Bugs and other small animals can thrive in pastures if the livestock management is done well. The stock numbers and types are important.
Did you know that more than 70% of the world’s fish stocks are over-fished, depleted or collapsed?
We could also consider the impact of our decisions about textiles, timber and metals, on wildlife and ecology. The average person in the UK now buys over four clothing items a month! Less than 1% of clothing textiles is recycled. The waste mounts up. Forests are destroyed to make way for cotton plantations. Even if organically grown, cotton monocultures destroy habitat of thousands of species of butterflies, moths, termites, wasps, bees, and other bugs. Ironically, the cotton crop is then a sitting target for the bollworm moth. Genetically modified cotton was developed to overcome bollworm problems. A few countries resisted the siren call of GM cotton, and use integrated pest management (IPM) instead. They have lowered costs and increased yields.
While worrying about cotton, let us not forget synthetics and the huge problem of microplastics. In 2016, for example, 65 million tons of plastic textile fibers were produced. They do not decay. They are found everywhere on the planet, from the Arctic to the ocean depths. Ingestion of microplastics causes problems for marine life. The dyes cause disease, and can kill corals.
The action list for this chapter focuses on reducing waste. Think before you buy, think before you throw away. If you can, switch to consumption of locally sustainably produced goods.
The action lists that close each chapter get longer, the connections get wider. Politics and the economy might not be the direction you expected from this book, but these topics are all part of the connected system, and all need consideration and action. Termites and corals co-operate within their colonies to create and maintain large healthy populations: we can do it too. (Corals are symbiotic associations of bugs (coral polyps, which form the exoskeleton) with several thousand species of animals and plants living within. Algae provide oxygen and carbohydrates.)
Big investors own shares in seed companies, just to make money. They have no interest or incentive to protect bugs or any aspect of the ecology. “It’s as if some beetles decided to take all the ants’ food supplies even though they cannot eat or use them. Money accumulation is hard to eat.”
Frustratingly, vested interests have too much power in decisions that affect large groups of people. We tend to avoid tackling entrenched societal problems. Vicki suggests three big areas to understand and deal with: poor governance and politics; inequality and poverty; runaway consumerism and waste. If you only wanted to read about saving beetles, you might be tempted to put the book down at this point. However, in order to save beetles, we need to look at the underlying causes of beetle die-offs.
Decisions on land use are often made by corporations and investors less focused on protecting biodiversity, and more on profits. We need to show them that enlightened self-interest can protect their financial success for the long haul. Some corporations are seeing this now that climate chaos is biting hard. Pushing humans to get three-quarters of their calories from just four crops (soy, wheat, rice and maize) may bring in fast bucks, but gives little resilience against climate change and extreme weather conditions, and is bad news for biodiversity.
Research has shown that as social inequality grows, so does harm to biodiversity, which leads to more inequality. Financial pressure from profit-seekers drives down wages, leading to a demand for ever cheaper food, spiraling to lower costs of production. They wring out higher short-term yields. Sustainability of food production goes to the wall. Desperate people take desperate measures to cover their basic survival needs. In 2020, the UN announced: “to bend the curve of biodiversity loss, we need to bend the curve of inequality.”
The action list for this chapter is over 5 pages, demonstrating the broadening of the goals. Campaigning, lobbying and voting; pushing governments and economists to balance social and environmental concerns and work for sustainable outcomes; requiring corporations to show much stronger accountability for all the results of their activity; supporting companies that are taking steps to lower their environmental damage and increase co-operation with others, strengthen international treaties and hold nations to their commitments on biodiversity and limiting climate change.
This probably sounds overwhelming, but “You don’t have to rebug alone”! You can join (or start) local organizations working on an issue you feel strongly about. The book contains a directory of some organizations (mostly in the UK). There is some help on starting lobbying, which most of us have not done before. The resources include guides on campaigning and influencing people. You can reduce your own carbon footprint and encourage others to do so. Big change is needed, but some days it’s restorative to “clean our own house” rather than go out lobbying.
We like to eat lettuce year round, and have put time and energy into finding the varieties and planting dates that work best here in Central Virginia, as well as how to get the best results in each season. Recently I revised our lettuce schedules, partly to take account of hotter weather arriving earlier in the year, and also to even out the harvest dates.
I have frequently written blogposts about growing lettuce. And I have a whole year of Lettuce for the Month posts. See here for the overview, or click on the month you want to know more about. These posts are mainly about our favorite varieties for each time of year.
Back in 2006, I wrote Lettuce: Organic Production in Virginia for VABF. We’re now in Winter Hardiness Zone 7a. Back then we were 6b. Read this publication for details you are hazy on, but see our updated Lettuce Varieties List and Lettuce Log in this post.
Choose appropriate lettuce varieties for each time of year.
Sow several varieties each time to spread the harvest season and the risks of poor germination. I like to use something fast, something slow; at least one red; a romaine, a bibb and a couple of leaf types.
Consider multileaf lettuces too, Salanova and Eazyleaf brands. They are bred for uniformly small leaves, with more texture, loft and flavor than baby mixes and faster harvesting. Transplanted 6″–8″ (15-20 cm) apart they produce 40% more than baby leaf mixes. The full-size plant can be harvested as a head, providing a collection of bite-sized leaves. Or just one side (or the outer leaves) of the plant can be cut and the plant will regrow for future harvests. Growing multileaf heads takes 55 days, compared to 30 days for baby lettuce
Our recent changes to our Lettuce Varieties List include switching over from “Early Spring” varieties to “Spring” varieties at the end of February rather than the end of March. This means we only make 3 sowings of the early spring varieties, and we need to stop buying much seed of those varieties! Next year I might even abolish that category and those early varieties to simplify life.
The spring varieties we now sow from February 28 to April 22. We used to sow these until May 15. We’re still making 5 sowings of those, but the dates have moved earlier.
On April 23 we switch over to our Summer varieties, which we make 20 sowings of, until August 14. (Buy lots of seed of those varieties!) We then switch to nine sowings of Fall varieties, until September 7.
From September 8 to the end of September we use our cold hardy varieties. These 9 sowings include those for the greenhouse and hoophouse, which will feed us all winter.
You’ll need a large screen, a magnifying glass or the ability to expand the image.
We like to grow a balance of leaf lettuce and head lettuces, and, in winter, baby lettuce mix too. We harvest the baby lettuce mix when 3″–4″ (7.5–10 cm) tall, cutting 1” (2.5 cm) above the soil. We harvest leaves from the big lettuces the rest of the time. Baby lettuce mix is very pretty, but I actually prefer the juiciness and crunch of big lettuce.
Keys to year round lettuce
·Store seed in a cool, dry, dark, mouse proof place.
·Grow your lettuce quickly, for high quality and flavor, using good soil preparation and high organic matter.
·Learn the skills of lettuce germination in all weathers. Minimum soil temperature for germination is 35°F (1.6°C). Optimum temperature range for germination is 68°F–80°F (20°C–27°C).1/4″–1/2″ (6–10 mm) deep is ideal. Good light.
Watch the temperature – Germination takes 15 days at 41°F (5°C), 7 days at 50°F (10°C), 3 days at 68°F (20°C) and only 2 days at 77°F (25°C). Germination will not occur reliably at temperatures hotter than 86°F (30°C).
Keep watching the temperature – Optimum growing temperatures are 60°F–65°F (15°C–18°C), Some growth occurs whenever the temperature tops 40°F (4.5°C).
·Choose good locations! We grow lettuce outside from transplants from February to December (harvesting from late April); in a solar-heated greenhouse from September to March (harvesting leaves from November) and in a solar heated hoophouse from October to April (harvesting leaves from November, and whole heads in April). We also sow baby lettuce mix in the hoophouse from October to February, for harvest multiple times from December to April.
·Use shade cloth on hoops in hot weather
·Use rowcover in cold weather, or plant in cold frames, greenhouses or hoophouses.
Lettuce under shade cloth. Photo by Nina Gentle
Grow a consistent lettuce supply using succession crop planting
To have a continuous supply, it is important to plant frequently, at intervals adapted for the time of year. The gap between one sowing and the next gets smaller as the year progresses; the gap between one transplanting and the next does likewise. The number of days to reach transplant size dips to 21 days in the summer, then lengthens as the weather cools and the days get shorter.
We made a Lettuce Succession Crops graph using our records for sowing date and harvest start date. From this we determined the sowing dates to provide us with a fresh harvest (120 heads of lettuce, or equivalent) every single week. We made a Lettuce Log with our planned sowing, transplanting and harvest dates. This is explained in my slideshow Lettuce year round.
Lettuce Succession Crops Graph
Recently I fine-tuned this in light of more recent records. In some cases we had been led astray by a spreadsheet date calculator that was based on 30 day months in a 360 day year! Not reality! We also had data showing that transplants were not always ready on the dates we had thought, probably due to a mistake in an earlier year when we were unable to transplant on time, and repeated the delayed date the next year. Most of the tweaking was in early and late spring, and then in August.
Tips for growing good quality lettuce
I recommend transplanting lettuce (other than baby lettuce mix) at 4-6 true leaves (3-6 weeks of age). It is worth learning good transplanting skills, so that plants thrive, even if transplanted in mid-summer.
Water enough, with an efficient irrigation system. Water new transplants daily for the first 3 days, then every 4-7 days after that. Lettuce needs a relatively large amount of water throughout its growth. Deeper weekly waterings equivalent to 1” (25 mm) of rain are better than frequent superficial irrigation – roots will grow deeper, giving the plant greater drought-resistance.
To make best use of space and time, plant lettuces 10-12” (25-30 cm) apart, in a hexagonal pattern. If you plant too close, you are restricting the size of the lettuce. If you plant with more space than needed, you will waste time dealing with more weeds!
Transplanting gets a head start on weed control, which is important from planting to a couple of weeks before harvest. Don’t waste time hoeing lettuce you will be harvesting next week. I generally find that if I hoe once, a couple of weeks after transplanting, that is all the weed control I need at the fast-growing time of year. We like the stirrup, or scuffle, hoes, which are safer in the hands of novices than sharp edged hoes, because the blade is in a closed loop.
Some growers use black plastic mulch, but I hate filling the world with single use plastic, so we don’t do that. Some others use landscape fabric with melted holes at the right spacing. I used this for strawberries and liked it. I’m not sure I’d find it worthwhile for fast-growing lettuce. No-till growers can transplant into mulch, first making what we call “nests” at the appropriate measured spacing. It’s tempting to skip the measuring, but if you drift from a 12” (30 cm) spacing to a 15” (38 cm) spacing, you will end up with fewer lettuces!
For those who like to direct sow lettuce, you could prepare the bed, let it rest for a week (watering it), then flame or lightly hoe the surface before sowing to remove a flush of weeds.
Bolting and/or bitterness are more likely with under-watering, long days, mature plants, poor soil, crowding, high temperatures, and vernalization—once the stems are thicker than 1/4″ (6 mm), if plants suffer 2 weeks of temperatures below 50°F (10°C), followed by a rapid warm-up.
Deal promptly with pests and diseases. Aphids, cutworms, slugs, rabbits, groundhogs and deer all like lettuce as much as we do. If you find your lettuces melting down with fungal diseases, you can, of course, commit to better crop rotation. You can also consider solarizing beds for next year’s lettuce. You need a minimum of 6 hot weeks in which to cook the soil-borne disease spores by covering the prepared beds tightly with clear plastic. Old hoophouse plastic is ideal – construction plastic does not have the UV inhibitors that prevent the plastic shattering into shards.
Aphids can get out of control in early spring as they become active before their native predators, such as ladybugs, emerge from hibernation. We have a particular problem in our hoophouse and in our greenhouse on the eggplant, pepper and tomato transplants from mid-April to mid- to late-May depending when we manage to get them under control.We’re planning now, so we can be ready next spring.
There are many kinds of aphids. The lifecycle of aphids starts in spring with eggs hatching into wingless females that give birth via parthenogenesis to more females. Within a week, one female can produce 100 clones, which can repeat the process at the age of one week.This continues until adverse weather or predators trigger production of a generation of winged female aphids that moves to new plants. Later in summer male aphids are born and females lay fertilized eggs that overwinter on host plants, to hatch the following spring.
Climate change is making the problem worse: for every 1degree Celsius rise in average temperature (about 2 F degrees), aphids become active two weeks earlier.
Organic Integrated Pest Management
I have a blog post about our organic integrated pest management, a step-by-step method of pest management which starts with actions least harmful to the ecosystem, only employing biological controls such as botanical sprays and selective pesticides if necessary after all other steps have been insufficient.
I recommend the ATTRA online publicationOrganic Integrated Pest Management. Each of the 22 pages is a poster, complete with good photos and concise clear info. Extension.org has an article on Organic Integrated Pest Management that explains how to tackle pest problems one step at a time with ecologically-based practices, starting with actions chosen to reduce the chances of the pest ever getting a grip on your crops.
Steps in Organic Integrated Pest Management:
Prevent infestation: Cultivate a good environment for your crops: healthy soil, sufficient space, nutrients and water, suitable temperature, soil pH. Practice crop rotation to reduce the chances of pests and diseases carrying over from one crop to the next. Clear old crops promptly, so they don’t act as a breeding ground for the pest. Choose suitable varieties that resist the pests you most expect.
Cover or protect the plants physically from the pests (mulches to stop soil-dwelling pests moving up into your crops, netting, rowcover, planting diverse crops, and even growing trap crops)
Provide habitat for natural enemies and other beneficial insects
Monitor crops regularly at least once a week and identify any pests you see.
Introduce natural enemies of the pest (bacteria, fungi, insect predators or parasites)
Hand pick and kill the pests if the pest population is above the action threshold. Many fruit and root crop plants can take 30% defoliation before any loss of yield. Where the crop is the foliage, this may be too much!
Use biological controls (often derived from natural enemies) if the damage is still economically significant after trying the earlier steps in the process.
Applying these principles to dealing with early spring aphids
1.Prevent infestation If you act before the aphids arrive, you can use a fine mesh netting to keep them off your plants, but monitor to make sure no aphids have got inside the net. Control ants (which farm aphids for their sweet excretions). Reputed repellents that I have not tried: dilute garlic, onion or chilies with water; diatomaceous earth (health hazard from inhaling gritty particles); vegetable oils.
2.Cover or protect physically. You could try trap crops of nasturtiums to draw aphids away from your crop, but how much of your space do you want to devote to nasturtiums, and how do you deal with them then? The same choices as on food crops.
3.Provide habitat for natural enemies. Plant for a continuous supply of insect-attracting blooms, that flower early in the year and attract aphid predators such as ladybugs, lacewings, syrphid flies (hoverflies), damsel bugs, big-eyed bugs, and spiders. Grow some early blooming flowers with pollen and nectar they can use as alternative foods. Sow seed in fall for earliest bloom.
Native annuals are some of the earliest bloomers that attract beneficial insects:
Tidy Tips (Layia platyglossa), a spring flowering wild annual in the aster (sunflower) family. The white tipped yellow daisy like flowers are 2” (5 cm) across. A native of California, it grows up to 2ft (60 cm) tall. The seeds attract birds. Flowers have special value to native bees. Tolerates cold to -5°F (-20°C). Likes full sun. Seed is widely available. To start indoors, sow seeds 6 to 8 weeks prior to planting outside. Do not cover; seeds need light to germinate. Seeds germinate in 8-12 days at 65-70° F (18-21°C). Temperatures above 70°F (21°C) inhibit germination.
Information from Laura Blodgett in the Daily Improvisations blog, Southwest Idaho: Starting Tidy Tips from seed in February was too early. The seeds sprouted within a few days. The plants were sturdy from the start. It was too cold to plant them out, but they had so much growth that they were cramped in their small pots. There were enough warm days in March to harden them off, even though temperatures got down in the mid 30’s F (1-3°C) a few nights.
Meadowfoam (Limnanthes douglasii) commonly known as poached egg plant and Douglas’ meadowfoam. The five-petalled 1” (2.5 cm) flowers have yellow centers and white edges. A fast-growing bushy annual, very attractive to hoverflies, butterflies and bees. Requires insect pollination. It grows 6-12” (15-30 cm) tall and wide. Hardy to zone 2. Germinate below 60°F (16°C) (in fall?). May need light for germination. Easy to transplant, but don’t let it dry out! If spring-sown, may not flower until early summer (too late for aphid control). Temperatures below 55°F (13°C) will hinder flower opening as well as honey bee flight.
Baby blue eyes (Nemophila menziesii) is a low spreading, shrub-like plant with succulent stems and flowers with six curved blue petals. It grows 6-12” (15-31 cm.) high and wide. You can expect baby blue eyes flowers in late winter where temperatures are moderate and the plant blooms until late spring to early summer. Wait until soils warm to nearly 60°F (16°C) to sow seeds. Sow shallowly, about 1/16 inch (2 mm) deep. Baby blue eyes flower will germinate in 7-10 days with cool weather and short days. Baby blue eyes self-seeds readily but does not transplant easily. Butterflies, bees, and other helpful insects use the nectar as food. Pinch the tips of the growth to force bushier plant formation. Once the plant has flowered and seed heads formed, cut them off and dry them in a paper bag. Shake the bag after a week and then pick out the larger pieces of chaff. Transplant carefully 6-8 weeks after sowing. Sow in the fall, (but not frost-hardy? winter hardy in zone 7 and warmer?) then blooms from early spring to mid-summer. Baby blue eyes will die out if too hot in summer. Water frequently, provide shade (without hindering insects!)
Borage is a warm-season annual, fast at producing nectar, taking about 8 weeks to flower from sowing. Borage grows 1-3 feet (30-90 cm) tall and wide; it blooms from early summer until the first frost in fall. Borage can be started indoors 6-8 weeks before the last frost. Seeds germinate in 7-10 days. Transplant borage seedlings outdoors after the last spring frost. Be careful when transplanting not to damage the taproot. Seeds can also be sown in the fall and will germinate the following spring.
Alyssum is a small plant we have used in broccoli and cabbage beds to attract beneficial insects. Sweet alyssum attracts three main groups of predatory beneficial insects a) Minute pirate bugs (they eat aphids, thrips, mites, psyllids, and insect eggs), b) Parasitic wasps (they lay eggs in aphids, beetles, flies, moths, sawflies, mealy bugs, and scales. The larvae hatch and eat their way out, killing the host. c) Hover flies, aka syrphid flies (the larvae feed on aphids). Alyssum flowers also attract butterflies and bees. Buy Sweet Alyssum, not the ornamental cultivars.
Shungiku, Chrysanthemum Greens, Chopsuey Greens, Glebionis Coronaria, is in the aster family, Asteraceae. It is native to the Mediterranean and East Asia. The plant’s greens are used in many Asian cuisines. Shungiku is easy to grow and the leaves, young shoots and stems can be eaten. Leaves are aromatic, with a strong flavor. Some describe the taste as between celery and carrots. Even the petals and seeds can be eaten. Small House Farm grows this (and sells seed). Bevin says it does attract bees, butterflies and predatory insects. It would probably do well in the winter hoophouse, and could be provoked into bolting early in the spring.
Dill is a biennial umbellifera, often grown as an annual. It is easy to grow, germinating in 10-14 days. It doesn’t transplant easily (although we do it every year without a problem). It does self-seed readily, so to prevent this, cut the seed heads before the seeds turn tan. The leggy plant grows 2-4 ft tall (60-120 cm) and half as wide. Each plant grows only one hollow stem with an umbrella-shaped flower head from mid-summer to fall (too late for spring aphid predators). Dill tolerates cold and heat, but will likely die back to the ground after the first hard freeze. It might not be the easiest to include in a hoophouse.
Angelica is a biennial that can flower in the spring of its second year.
Phacelia is a particularly useful perennial plant in early spring if it has overwintered as it is an early pollen source for bees coming out of hibernation. Sow in the fall for early spring blooms – Phacelia will survive mild frosts to bloom in spring. It winter-kills at approximately 18˚F (-8˚C). The seeds need darkness to germinate, and then the plants like to grow in full sun. Phacelia flowers from 6-8 weeks from spring sowing for a period of 6-8 weeks with lavender blooms that attract syrphid flies, bumblebees, honeybees and native bees, and also aphid predators like hoverflies and parasitic wasps. It can grow 6-40” (8-100 cm) tall, given the chance.
Yarrow is a perennial, hardy to zone 5. Common Yarrow (with flowers that range from white to red) is hardy down to zone 3. It attracts an array of beneficial insects. In addition, the scent of yarrow repels deer and mosquitoes.
Fennel,Foeniculum vulgare (common fennel), is an herbaceous perennial commonly grown as a summer annual. 5-7 ft (1.5-2 m) tall; each stem branches near the top and each branch ends with a flat-topped cluster of small yellow flowers; fennel looks very much like dill but is taller and coarser. Fennel blooms from mid-summer to frost. Too late and too tall for our goal of attracting spring aphid predators in the hoophouse.
Coyote bush, (Baccharis pilularis), also called chaparral broom, is a native shrub related to sunflowers. It may be a low-growing shrub or an erect tall bush, depending upon its growing conditions, and so may not be a good candidate for a potted plant in the hoophouse! It attracts syrphid flies, as well as bees and butterflies, with its abundant winter bloom.
Dandelions. If you decide to trust to weeds to feed your beneficial insects, take care about how much seed they sow!
4.Monitor crops at least once a week
5.Introduce natural enemies: We do have an aphid parasite in the hoophouse as we do find mummies, but not enough to control an aphid outbreak in spring. Parasitic wasps for aphids include
Aphidus colemani eggs hatch into larvae which feed on the nymphs from the inside, the nymph swells and hardens into a leathery, grey or brown colored mummy similarly to effects of Aphelinus abdominalis. Once larvae mature, adult A. colemani wasps chew their way out of the aphid mummy and emerge to seek out aphids. These parasites are a good choice for year-round use (in greenhouses and outdoors) as the short days of winter do not affect them. Optimum Conditions: 70-77°F (21-25°C), 80% relative humidity. Release rates: 500-3,000 per acre, 2-3 times at one week intervals, depending on the extent of infestation. This product controlsaphids, especially melon and cotton aphids Aphis gossypii, but also attack green peach aphid Myzus persicae, tobacco aphid Myzus nicotianae and bird cherry-oat aphids Rhopalosiphum padi. Price $243 for three batches of 500, including overnight shipping, from Arbico Organics.
Aphidus ervi will consume all types of larger aphids, especially the potato aphid, Macrosiphum euphorbiae, and the glasshouse potato aphid, Aulacorthum solani. It also parasitizes Myzus persicae var. nicotianae, as well as aphids such as Sitobion sp., Schizaphis sp., Rhodobium sp., Acyrthosiphon pisum and others. Use Aphidius ervi especially when aphid infestations are just beginning, as control will be easier to achieve before the aphid population’s explosion. Aphidius ervi are shipped in a 125 ml bottle that contains at least 250 mummies and adult aphid parasites. The bottle has a ventilated cap for optimum humidity. A sugar-water feeder ring ensures adult survival. Release the emerged adults within 18 hours of receipt. The parasitized aphid swells and hardens into a leathery, grey or brown colored mummy. The first mummies can be seen in the crop approximately 2 weeks after the first introduction. Use at the rate of 1 adult per 20-100 sq ft (1 per 2-9 m2) for preventative use. 250 mummies is sufficient for 5000-25,000 sq ft (460-2300 m2). Dose rate may be increased 5-fold for hot spots. Introduce A. ervi weekly for at least 3 weeks. Cost from Arbico is $101 including shipping each time, $303 likely. Monitor weekly and make further introductions as required. When pruning leaves, check for parasitized aphids (brown mummies) and if present, keep these leaves in the greenhouse until new parasites emerge. Because they fly as soon as they emerge, you need to cover doors and windows with mesh screens.
Another option is a predatory gall-midge, Aphidoletes aphidomyza, the larvae of which hunt and kill aphids. Kills over 60 species of aphids, especially those in greenhouses and hoophouses, including green peach aphid Myzus persicae; andthe hemlock woolly adelgid Adelges tsuga. Optimum conditions: 64-77°F (17-25°C) with RH of 70%. Shipped as pupae. The adults hatch within 1-12 days. After hatching, females lay eggs among aphid colonies. The eggs develop into larvae, and seek out adult aphids, injecting a toxin in their legs to paralyze them. Then they bite a hole in their thorax and suck out the body contents. Use 1 predator per 10 sq ft (1 m2), 2-3 predators per 10 sq ft (1 m2) for heavier infestations or 4,500 per acre (0.4 hectare) weekly until infestation subsides. 1000 for a 96x30ft (29×9 m) hoophouse, cost $125 including shipping per week, perhaps $375 total.
Green Lacewing adults feed on nectar, pollen, and aphid honeydew, and the larvae are active predators of soft-bodied insect pests: aphids, thrips, whitefly, leafhoppers, spider mites (especially red mites) and mealybugs. After hatching, green lacewing larvae seek out prey – pest eggs, nymphs or adults. They feed for 2-3 weeks, spin a cocoon, and emerge as adults 10-14 days later. Lacewings have the ability to tolerate wide temperature ranges and work well with most other beneficial insects. Green Lacewing Eggs:Best low-cost biological control for common garden pests. If you want to establish Green Lacewings at the beginning of the season or have a limited infestation, choose the appropriate numbers of eggs for your garden or greenhouse. It takes 3-10 days for larvae to emerge depending on the temperature and other environmental conditions. Repeat applications every 1-2 weeks. Green lacewing eggs are available in loose media or on hanging cards for easy release. Green Lacewing Larvae:Best for immediate treatment of a pest problem. If you have a more severe infestation, buy the larval frames or bottles, which provide the quickest means to control unwanted pests – the larvae arrive ready to feed. Adult Green Lacewings:Best for establishing a population. If you are treating a large area and want to create a stable population, buy adult lacewings. The adults come ready to lay eggs throughout the release area. They do not actively control pests themselves. Cost 1000 eggs on cards $30 each time; 1000 larvae $61 each time; 100 adults $85. All prices include shipping.
Ladybugs. live ladybugs are best used when pest numbers are low, but can be used to fight existing infestations. Ladybugs primarily feed on aphids, but will prey on a variety of other pests including mealybugs, thrips, soft scale, whiteflies and spider mites. Each adult can consume up to 5,000 aphids in a lifetime. The larvae eat 50-60 aphids per day.Optimum Temperatures: 62-88°F (15-31°C). Ladybugs are prone to flying away. Help keep them around and attract native species by planting perennial and annual flowering plants and by avoiding chemical sprays. Create shaded areas or plants with dense canopies to provide alternative habitat when conditions are not ideal. While these methods may not keep all the ladybugs on site, they should help. If you have had issues with ladybug flight, consider using Assassin Bugs or Green Lacewing instead. 4,500 for up to 2,500 sq ft (232 m2). Cost $20/1500 plus Overnight or 2nd Day Air shipping.
6.Hand pick and kill the pests if the pest population is above the action threshold. Handpicking aphids is likely impossible, so blast them off the plants with a water jet from a hose. This may decrease the population enough for natural predators to begin control.
7.Use biological controls. Failing success with the methods above, a soap spray can be effective, although aphid predators will also be harmed. We use 3 Tablespoons (15 ml) per gallon (3.8 l) of biodegradable Murphy’s Oil Soap, in a sequence of 3 sprayings 5 days apart. The soap needs to hit the aphids to kill them. Soak both sides of the leaves and directly spray any visible pests.Murphy’s Oil Soap is made from lye (potassium hydroxide) or sodium hydroxide, and vegetable oils with 2% of synthetic ingredients including trisodium MGDA, Lauramidopropyl dimethylamine oxide (a non-toxic purifying agent), sodium tallate. Official insecticidal soaps are made from potassium salts of fatty acids (potassium laurate).
Insecticidal soap works in several ways. The soap penetrates insects’ cuticles, which causes their cells to collapse and dry out. Soaps suffocate insects such as scale insects. Soap sprays are also somewhat effective against chiggers, earwigs, fleas, mites, scales, and thrips. They are not effective on chewing insects such as caterpillars and beetles.
You can make your own soap spray if you have some fragrance-free liquid soap. You do not need to include oil. Note that “dish soap” is actually detergent, not a soap at all, so don’t use that. Test your homemade spray on a small part of a plant first and wait 24 hours to see if there is any damage. Look for spotting, wrinkling, or browning of leaves. If you see any trouble, don’t use the spray.
Soap sprays can be potentially damaging to some plants. Crops that are susceptible to damage from soap sprays include cucumbers, squash, melons, beans, and peas.
Neem is a botanical insecticide effective against aphids.
Best Options for our Hoophouse in April and May
Looking at the options for dealing with aphids and choosing those most compatible with pot-grown plants to flower in spring in our greenhouse and hoophouse, these seem our best chances:
·Cultivate a good environment for our crops.
·Monitor crops regularly once a week.
·Grow Meadowfoam from seed in the hoophouse in late October. Hardy to zone 2. Try February too.
·Grow Tidy Tips from seed in the greenhouse in February, pot up and move into the hoophouse just before flowering. Try starting some in late October too. Tolerates cold to -5°F
Grow Sweet Alyssum from seed started in February.
Grow borage form seed started in February. Move pots to hoophouse after April 1.
Grow perennial phacelia started in October and February for future years. Phacelia will survive mild frosts to bloom in spring. Protect from worse than “mild frosts”.
Grow yarrow from seed started in October and February. It is hardy down to zone 3.
Grow Shungiku from seed sown in late September, and provoked into bolting early in spring.
If we want to spend $100+ to deal with a bad infestation, buy 3 units of ladybugs.
This was day 7 of my Agroecology Tour of Cuba with the Organic Growers School (Monday January 13, 2020)
Dinner at the Garden of Miracles (Jardin de los Milagros Paladar) farm-to-table restaurant, with guest speaker, Rafael Betancourt
Overview of the Cuban Economy, Cooperatives and Politics
We rearranged the tables in a square, to better hear the speaker, Rafael Betancourt, talking about the Cuban economy, cooperatives and politics. First I’ll write about the talk, then about the restaurant.
The Cuban economy has changed from the export of plantation products (using enslaved people) to tertiary tourism, remittances from ex-pats in the US and training (medical and other). Sand and Sun tourism is waning, Agritourism could be increased. Farmers can earn more money by catering for tourists than from selling crops. “Cuba doesn’t export any food except apples.”
Rafael Betancourt believes it is geographically inevitable that the US and Cuba will come together. Right now we’re at a juncture. Obama’s executive orders were been rolled back by Trump. Cubans prefer the word “blockade” to “embargo” (which implies bilateral actions.) The Helms-Burton Act of 1996 included that US dollars cannot be banked in Cuba. It’s costly for them to keep moving suitcases of US dollars around.
The US and Cuban economies are entangled but limited. Food imports from the US are allowed but have to be paid in cash as soon as the product arrives. [This is different from what we were told about US chicken not leaving the US until it had been paid for in Euros and cleared the European Bank.]. Exports to the US are almost always prevented, except that tourists export rum, cigars, honey, etc.
“In this history of Cuba, Louis A. Pérez proposes a new Cuban counterpoint: rice, a staple central to the island’s cuisine, and sugar, which dominated an export economy 150 years in the making. In the dynamic between the two, dependency on food imports—a signal feature of the Cuban economy—was set in place.”
U.S. rice producers resisted Cuban efforts to expand rice production, because they relied on the Cuban market for rice. Cuban sugar growers relied on the U.S. market. U.S. growers prepared to cut the sugar quota to control Cuban rice markets. In the 1950s, when revolutionary tensions in Cuba were strengthening, U.S. rice producers and their allies in Congress clashed with Cuban producers supported by the Batista government. U.S. interests won out, contributing to undermining Batista’s ability to govern. Cuba’s inability to be self-sufficient in rice production continues to this day, but U.S. rice growers have lost the Cuban market. In the face of the U.S. embargo, Cuba buys low quality rice from Vietnam, that does not sell well in Vietnam. They are learning Vietnamese water-conserving rice-growing methods.
Cuba does not need to import eggs, but they do import chicken feed.
Food waste from restaurants may be taken home by the workers, or sent to schools and hospitals, or become pig food. There is no State strategy.
Portion size: there is a scarcity mentality in Cuba, leading to a frugal use of resources.
Cubans going overseas bring back empty Tropicana juice jugs in their luggage.
Recycling varies from place to place. The State purchases cans, metal, plastic and paper. They sell the products back to the manufacturing company.
Climate change and resiliency: In the US, food waste accounts for more than 20% of greenhouse gases. Cuba has a strategy for reducing greenhouse gases. Cuba didn’t make many of the greenhouse gases, but will be strongly impacted by climate change. The coastal resorts are vulnerable to sea level rise, and suffer badly from hurricanes. They have a big Reforestation Project, adding more trees every year. Cuba is committed to 20% renewable energy sourcesby 2020. Cuba became the first country in the world to completely phase out incandescent light bulbs.
The top five Cuban products Rafael Betancourt would like to see exported to the US: Cancer vaccine, other pharmaceuticals, high technology software, beer, services. Currently the label “Remittance” covers business transactions.
Academic Exchanges: A US institution would need to partner with a Cuban academic institution. Cuba could help with rice post-harvest equipment and know-how; Milk production (they have a very cheap method of producing 1 liter/day); Cattle feed; Biofuels using sugar bagasse; They could use help with setting up a certifying board and certifying and exporting organic food; They would like to provide their own organic seeds (many Cuban vegetable seeds are imported, but row crop seeds are grown there).
The story of the CUC: The US embargo was designed to push Cuba towards the USSR. Most imports came from the USSR. When the Soviet Union collapsed, Cuba experienced an 80% reduction in imports and exports. Remittances from Cubans overseas helped island survival. Tourism grew, and hard currency started coming in, but the banks didn’t touch it. Cubans became allowed to possess hard currency, and a chain of stores opened, selling goods in US$.
The CUC was invented in 1994 after the collapse of the Soviet Union, to substitute for US$, which people were then not allowed to spend. People converted their dollars into CUCs. Domestic tourism increased, and the CUC stimulated imports and suppressed exports. The exchange rate was about 24 Cuban pesos to 1 CUC. The State promises to honor the value of the peso. The CUC was phased out on January 1, 2021, after that plan being a kind of a secret. The duty-free shop at Havana airport sells goods for US$ or pesos, but not CUCs. We were warned not to take CUCs out of the country, hoping to use them in the future. (US banks and currency exchange bureau don’t deal with Cuban money at all.) The Peso is now officially set at 24 Cuban pesos to 1 US dollar
Garden of Miracles (Jardin de los Milagros Paladar) farm-to-table restaurant
We visited the restaurant roof garden, which supplies the restaurant. There were table-top beds of greens, and beehives. We saw it in the dark, so my photos and impressions are murky! I believe they must buy a lot of their ingredients from elsewhere.
Here is a table of vegetable seed germination temperatures. These apply to soil temperatures when you sow directly in the ground, and to air temperatures when you sow indoors in small containers. If your indoor air temperature is not warm enough when you want to sow your chosen crop (watermelons, anyone?) you can make a small warm place, or use a professional heat mat, or, for a small scale, germinate seeds in an instant pot! If you have one of these handy cooking devices, check the lowest setting. Perhaps labeled for making yogurt, it might be 91°F (33°C). Look at my chart below and see if your seeds will germinate at that temperature. You’ll have to experiment for the seeds which germinate well at 86°F (30°C) but not at 95°F (35°C). Don’t try this with spinach or lettuce! You might be surprised to see that some cool weather crops, like broccoli and cabbage, can germinate just fine at high temperatures!
You can see my chart is a work in progress, so if you can add any info, please leave a comment on this post. Bold type indicates the best temperature for that vegetable seed. The numbers indicate how many days it takes that seed to germinate at the temperature at the head of the column. Where I don’t know the number of days, I have put “Yes” if it does germinate at that temperature, “no” if I think it doesn’t and a question mark where I plain don’t know. I would love to know, so if you can resolve the uncertainties, please speak up! I’ve also used the words “best’, “min” and “max” which I hope are self-evident.
To measure the temperature of the soil outdoors, I recommend a dial-type soil thermometer. Ignore the vague guidelines on Min/Optimal/Max and use the table above. The usual practice is to check the temperature at 9am each day, and if you are unsure, check again the next day. In some cases it is best to get 4 consecutive days of suitable temperatures, or even (in spring!) a few days of rising temperatures.
Harbinger weeds of spring and fall
The progress of emergence of different weeds in the spring shows us how quickly the soil is warming up. I wrote about that here. In that post you can see photos of flowering chickweed, purple dead nettle, and henbit.
In the fall we will be waiting for the soil to cool enough to sow spinach. I have a blog post about thishere, and also photos of those three weeds as seedlings, which is what we are looking for in the fall, as an indication that the soil has cooled down enough for them (and spinach!) to germinate.
I have a post about phenology here.You can read some of the details of when to plant by natural signs. For instance, we sow sweet corn when white oak leaves are the size of a squirrel’s ear. I got excited this past weekend (April 10) when I saw wind-driven twigs on the ground with oak leaves definitely bigger than squirrels’ ears. But they were Red Oak, not White Oak.
The chart in that 2013 post has now got corrupted (at least it has on my screen), so here is a pdf
Phenology records are a useful guide to when to plant certain crops, and a way to track how fast the season is progressing right where you are. Phenology involves recording when certain wild and cultivated flowers bloom, seedlings emerge, or various insects are first seen. These natural events can substitute for Growing Degree Day calculations. Certain natural phenomena are related to the accumulated warmth of the season (rather than, say, the day-length), and by paying attention to nature’s timetable you will be in accord with actual conditions, which vary from year to year, and are changing over a longer time-scale.
Keeping your own phenology record will help build resilience in the face of climate change. Ours might be interesting to you, but unless you live in central Virginia, you can’t use our dates. You do need to make your own. This can be a great home-schooling project, or a crew I-Spy competition, or a calming end-of-day walk around your gardens.
This was Day 7 of my January 2020 Agroecology trip with Organic Growers School. This day we studied ecology, climate change, the effects of extractive agriculture, deforestation, reforestation and responses including Bioreserves and urban permaculture gardens.
To read other posts in this series, click the Cuban Agriculture category. Click this link to see a short video about the OGS Cuba Agroecology Tour. It goes live on April 14.
FANJ (Antonio Núñez Jiménez Foundation for Nature and Humanity) Havana
After breakfast at our casa, we rode our tour bus to FANJ (Antonio Núñez Jiménez Foundation for Nature and Humanity), a non-governmental cultural and scientific institution, dedicated to the research and promotion of environmental protection in relation to culture and society. We were given a tour of the museum and library. Roberto Pérez Rivero, the PNS-FANJ Director, gave us a talk “Cuban Environment, the challenge of climate change and development: an environmental education approach.” It covered science, urban agriculture and food security in Cuba.
We sat in the library around the glass topped tables of artifacts. National treasures and plastic lawn chairs!
There are 11 million Cubans, the population is not growing. The island of Cuba is only 30 miles wide at the thinnest point, and so the country is heavily influenced by the ocean. There are three or four ecosystems: sand beaches, mangrove swamps, bush (shrubs) and trees, seagrasses [maybe seaweeds?].
Biologically speaking, Roberto Pérez Rivero says the Caribbean is a province of the Amazonian Rainforest. A big project associated with FANJ was a journey in a large hollowed tree canoe, from the Amazon to Cuba. I didn’t understand everything. We saw the canoe and some photos and various artifacts from that trip.
In the eighteenth century, ship-building was important in Cuba. There was a “Forbidden Forest” reserved for shipbuilding. In 1769, the Santisima Trinidad was built in Havana, and was possibly the largest warship in the world at that time. It fought on the Spanish and French side against Britain in the US War of Independence.
No gold was found in Cuba, so the colonizers made plantations of several crops. Two species of tobacco, Rustica and Virginia were hybridized. Haiti had been the main coffee producer in the region, up to that point. Sugar cane came later on, from New Guinea, in the time of Columbus.
The Toxic Acids of Cuba: Rum, Tobacco, Coffee and Sugar.
There used to be three enslaved people (they say “slaves”) per white person. The plantation system shaped the environment. 90% of the land had been forests of all kinds. There were edible rats (vegetarian) living in the tree canopy, but no monkeys. By 1816 there was deforestation around the cities, but still 87% coverage overall. In 1909 there was only 54% tree cover left; in 1959 it was down to only 14%. The Cuban people (not the IMF!) worked on reforestation. In 2018 there was 32% tree cover (going up!)
There are 26 types of forest in Cuba, a “miniature continent”, including 4 areas of pines. This is the southern limit (20°N) for pines, which don’t grow in tropical areas [such as Jamaica, as I’d noticed on my trip there.] There are 40 million arable acres. Article 27 of the Constitution of the Republic of Cuba, 1996 revision, lists environmental problems:
Land degradation (heavy Soviet tractors, mono cropping).
Bauxite versus forest.
Contamination (pollution). During the Special Period businesses collapsed and pollution decreased; waste was converted into resources.
Loss of biodiversity, although this was less bad in Cuba than in other Caribbean countries; there are 240 protected areas.
Lack of water: in the dry season, water is needed for agriculture; more CO2 means more humidity (more water is trapped in the air).
Impacts of climate change; amphibians are being strongly affected. It’s better to protect ecosystems than individual species.
Bioreserves of the Biosphere: There are six Natural Areas designated as Reserves. Fishing is illegal if from a Styrofoam raft. [? I cannot explain this part of my notes!] Another speaker told us there is no fishing industry in Cuba – fish is imported.
Cuba reduces the threat of climate change by making preparations. They have 72 hours to prepare before each hurricane, thanks to Russian radar. The mangroves act as a “Live Task Force”and block storm surges.
“Dinosaurs did not go extinct, they evolved into birds” Birds can fly away. Roberto Pérez Rivero is an Informed Optimist. The Apocalyptic Vision doesn’t serve us.
2000: The Antonio Núñez Jiménez Foundation and Urban Agriculture Urban Agriculture Notes, Published by City Farmer, Canada’s Office of Urban Agriculture
2006: The World Wildlife Fund, In its 2006 Sustainability Index Report, using a combination of the United Nations Human Development Index (a measure of how well a nation is meeting its nutrition, water, health care, and education needs, etc.) and the Ecological Footprint (natural resource use per capita), determined that there is only one nation in the world that is currently living sustainably — and that nation is Cuba. The Report states, “No [other] region, nor the world as a whole, met both criteria for sustainable development.”
2007: View the 53 minute Cuban Permaculture documentary, The Power of Community: How Cuba Survived Peak Oil...Cubans share how they transitioned from a highly mechanized, industrial agricultural system to one using organic methods of farming and local, urban gardens after they lost global support in the early 1990’s. Roberto Pérez, a well-known exponent of this Cuban approach to ecology, can be seen in this documentary.
2008:Click HERE for a three-part talk by Cuban permaculturist Roberto Pérez that delves deeper into Cuba’s green revolution, and a half-hour video Peak Moment: Learning from Cuba’s Response to Peak Oil
Lunch on our own: I don’t remember what or where I ate. Or what I did in the afternoon. I probably ate my leftover pizza at the casa. I might have done some emailing. I’m surprised I didn’t write anything down. It’s hard to imagine I frittered away a whole afternoon of this special time! But I do remember dinner at the Garden of Miracles (Jardin de los Milagros Paladar) farm-to-table restaurant, with a guest speaker, Rafael Betancourt. I’ll tell you about that and their rooftop garden, another time.
Book Review: Greenhorns: The Next Generation of American Farmers
Edited by Zoë Ida Bradbury, Severine von Tscharner Fleming and Paula Manalo, Storey Publishers, 2012. 250 pages, $14.95.
This book isn’t new but deserves much more attention. It’s a collection of short pieces by farmers about things they learned as new farmers that they want to pass on, to save newbies (greenhorns) making those mistakes. Because it is personal anecdotes, this is easy to read, despite the seriousness. Greenhorns presents thought-provoking material, so you can usefully read one piece in a spare minute, and then think about it while you do a routine task. It’s a good companion volume to the more technical books on starting to farm.
There are fifty different short pieces, clustered into topics such as Money, Land, Body/Heart/Soul, Purpose, Beasts, Nuts & Bolts, Ninja Tactics, Old Neighbors, New Community. The resource section is a tad old, but still contains good stuff.
This book is written for the people who are willing to “jump high hurdles and work long hours to build a solid business” around the love of farming. Severine quotes Thomas Edison “Opportunity is missed by many because it is dressed in overalls and looks like work.”
Some of the messages are encouraging: you will get stronger with practice using a hoe and working outdoors all day, and you can learn diligence, courage and resilience. Don’t expect to be perfect from day one! Especially if you are making the big transition from an urban, less physically-active lifestyle. On small budgets of money and time, it is important to take care of your health, including sanity.
You do not need to struggle alone! Look for opportunities such as incubator farms, where experienced farmers are nearby as mentors, and you rent land, greenhouse space and some equipment. “I laugh every time I stop with a hoe in my hand to text the other farmers to see if a tractor is free”, says Meg Runyan. Beginner farmer programs are another source of support.
Some of the stories act as reality checks, including this from Jeff Fisher: “Cut, cracked, and bleeding fingers are just the start of the physical hardships of farming.” “At the end of each day I was left with aches, pains, cuts, cracks, blisters, infections, stings and sprains.” Not all of those, every day, I want to add! Farming is a very physical lifestyle, so invest in maintaining and strengthening your body for a long career.
“I feel so alone sometimes. It’s overwhelming to have every decision weigh on me. . . Why did I choose to farm alone? I just wish I had some company. Frustrated and full of self-pity, I finish the lettuce in a huff. . . As I work, my tantrum begins to subside.”
You need a sturdy sense of your own worth. How will you deal with a potential customer complaining about your prices (and by implication down-valuing your work? Will you get defensive? Crumple into tears? Go on at length about your own self-doubts? Admit you are new and slower than an experienced farmer? Such issues can lead to Imposter Syndrome (chronic self-doubt despite external proof of your competence).
It can be helpful to learn how to reframe a situation and celebrate the half-full glass. Learn to appreciate rural life. Learn to make friends with neighboring farmers, for what you share in common, setting aside the differences. Listen to their advice, accept offers of help when you can. Build community, a wealth of human connections. How important is it to you to look different? As Vince Booth points out, “This project of finding common ground with people who voice conservative ideals would be a lot more daunting if our agrarianism wasn’t an honest attempt to embody the most fundamental of conservative tenets: There are limits to everything. Given that, I believe local farming can be a rallying point for those on the left and those on the right . . .”
Josh Morgenthau shares his realization that reality can crowd out the ideals (which are the root of the disdain some farmers have for the organic movement). He grew fruit without chemical sprays, but was he prepared to lose his whole crop and go out of business rather than spray? How great a benefit to humanity would that be? “Even from an environmental point of view, running tractors, fertilizing with organic fertilizer, and putting untold other resources, human and otherwise, into growing an organic crop, only to lose it on principle. . . well, that just didn’t seem reasonable.” “Getting today’s customers to accept apples that bear more physical resemblance to potatoes than to fruit turns out to be even more challenging than is growing them organically in the first place.”
Those with romantic notions about working with horses will find Alyssa Jumars’ story sobering. Ignorant bliss, obstinacy, passion and ambition are not the way to go. She learned that they had unwittingly taught their draft horses to throw a fit or act terrified, so the people would take away the work, talk soothingly and stroke their necks. This big problem split apart the farm partnership.
Some of the tales are cautionary. Teresa Retzlaff and her partner leased farm land from very nice people they knew. “Be sure to put everything you are agreeing to in writing. Be explicit. Then have both a lawyer and a therapist listen as everyone involved explains exactly what is being agreed to. And still have a backup plan in case it all goes to hell.” She doesn’t cast blame or say anything nasty, but clearly she speaks from experience.
Be realistic about your finances, consider loans and debts carefully. Have a backup plan, and regularly compare your daily realities with where you need to be financially. Don’t dig deeper into a hole. You’ll be putting your hearts, souls, energy, time, family and livelihood on the line when you take out a loan. Don’t rush to own and lose sight of your actual goal of farming. Bare land with no infrastructure is going to be hard to wrest a living from if you have no money left over for building the farm!
Luke Deikis advises walking the land before sitting down to discuss details with sellers (saves time drinking unnecessary cups of tea!) Even better, get a map and do a drive by before scheduling a meeting!
Ben Swimm writes about losing tools as part of a chaotic spiral that’s especially dangerous for new farmers. It’s connected with being over-ambitious, spreading yourself too thin, getting flustered and disorganized. This can lead downwards to a state of demoralization. Adding to the challenge is the seasonal nature of farming. It gets too late to fix a problem this year – you need to move on from this year’s mess and do something different next year. Triage is as valuable in farming as in hospitals.
Sarah Smith writes about farming while raising two young children. As a farmer-mama, “there are no vacations, Saturday gymnastics classes, or afternoons at the playground.” Sure, the kids thrive in the outdoor air, learn math making change at market, and develop good social skills by being around so many different people, but “on many days, all this comes at a cost to our family.” Being a farmer and a mama are both full-time jobs and among the most difficult in the world.
Evan Driscoll combined an unpaid 20 hour-a-week farming internship, 40 hours a week earning money, and childcare. He thought that was reasonable, on his way to becoming a farm owner. He hadn’t realized that having his partner in law school meant he’d be the primary caretaker for their child. That’s definitely something to clarify before you get too far down the road.
Maud Powell was shocked to find herself in the conventional women’s role on her farm, after her children were born, while her husband did the fieldwork. The couple apprenticed on a farm together, doing all the types of work interchangeably. She imagined continuing this way on their own farm after her first child was born: farming with the baby strapped to her back. Like many pre-parents, she underestimated the amount of energy and time breastfeeding and childcare would take. She also underestimated the love and devotion she would feel for her child, and how her focus would move from farming to mothering, and taking care of the household.
After her second child was born, her struggle continued. For efficiency in their time-strapped lives, they let their gender roles become more entrenched. This changed when they started growing seed crops. Preserving the fruits that contained the seeds increased the value of the kitchen work. Maud later branched out into community organizing around shared seed cleaning equipment, farm internships, and a multi-farm CSA. She became the one “going out to work” while her husband stayed home on the farm.
Farming includes many aspects we cannot control, including the sometimes devastating weather. Unexpected frosts, floods, hurricanes. As farm-workers, we learn to work outdoors, where the weather is a matter of personal comfort. But it is only as farm-owners that the weather affects our livelihood. We learn to do our best to prepare where we can, surrender when we must, and pick and up and rebuild afterwards.
Kristen Johansen says, after Hurricane Ike destroyed their chicken housing in the night, “It was our first year farming, and the learning curve was steeper than you can imagine. It was demanding, stressful, frustrating, exhausting, dirty and beautiful at the same time. When we took the leap into farming, overnight we became responsible for several hundred tiny little lives, and the weight of that responsibility was heavy.”
Climate change is undeniable; we must develop resilience. Ginger Salkowski says, “A successful new farmer in today’s (and tomorrow’s) climate has to have a serious package of skills. You have to be able to live with less. . . get very creative with very little money and time in order to make your season happen. You have to thrive on uncertainty. . . You need to be strong in body. . . You must be strong in mind . . . You must be strong in spirit: In times of high stress, there is grace to be found in pausing to observe the first sweet-pea blossom . . .”
Farming is mostly an exercise in managing chaos, as Courtney Lowery Cowgill points out. She shares her twin defeat of seeds that would not germinate and a hoped-for pregnancy that wasn’t happening. Proactive people make good farmers, and yet we must remember we can’t make everything turn out the way we want. We must learn not to blame ourselves for things we could not control or predict. While also getting better at predicting. “Farming in an ecologically responsible way involves good timing, and when we need to get something done, we git ‘er done!” (Paula Manalo)
Some of the stories describe unconventional (risky) ideas that helped the farmers get through a tough patch, like using a credit card with a year of zero percent interest rate to finance the first year of farming! Or getting a farm loan that didn’t allow for earning any off-farm money (very hard while starting up), followed (when that didn’t work out and they had to get off-farm jobs) by a home loan that didn’t allow any farming! “The irony of having to quit farming so we could finally get a loan to buy the land . . . was made even harder to swallow when we had to provide written assurance to the lenders . . . that although we had indeed spent five years running a ‘hobby farm’ we . . . now had nice safe real jobs, and only wanted to buy eighteen acres of land zoned agriculture-forestry so we could continue to live a ‘rural lifestyle’” “I can’t say I recommend lying to your bank as a road to farm ownership.”
Don’t feel a failure if you need some off-farm income to make the good life good enough. It doesn’t make your farming any less “real”! Casey O’Leary surveyed neighboring farmers and found she was not alone in needing some off-farm income. There is no shame in doing paid landscaping work two days a week to fill the financial gap. By embracing the part-time nature of your farm, you may be able to increase your dollar per hour, as Casey discovered. Focus on the best-paying farming and walk away at the end of the day. “My relationships with my lover, friends, and family have improved because of my ability to keep my farm in a part-time box.”
Some passages are about why we farm. If your goal is to grow nourishing food with and for those with limited access, while also meeting your own needs to farm full-time, then don’t focus on making money from farming. Find other sources to support your financial needs. Douglass Decandia had a dream of this sort, and found paid work with a Food Bank. “Most of us don’t need to search for meaning in our lives, because we see it every day. Thankfully, the work itself propels us on to the next task.” (Tanya Tolchin)
Jenna Woginrich is an office worker by day and “a farmer by passion”. She attributes her happiness and success to two things: “I always believed I would (not could, not might, but would. 2. And because I wrote it all down.” Only 2% of people with goals write them down, but of that 2%, 90% achieved their dream.
Emily Oakley and Mike Appel write about their decision to run their 100 member CSA of 50 crops on five acres, with just the two of them. It’s their full time job, and they designed their farm to fit this preference. Their goal is to be as small as possible while still making a living. What a refreshing perspective! Bigger means more responsibilities, more worries, and not necessarily more money. Their farm can be smaller because they are not paying anyone’s wages. Why pay for more land just so you can grow more food, so you can pay employees? Staying small also meant they can have an off-season break. The limitations are that there are no sick days; it can get lonely; it can put strains on the relationship.
Farming may not be easy, but it sure isn’t boring. Sustainable farming includes some pioneer spirit and also giving back/paying forward. Respecting other farmers, customers, neighbors. Mentoring newer farmers, sharing tools.
Some stories share the magic and the sense of connection with past farmers. Sarajane Snyder says: “Farmers, understand what you’re doing in the context of inter-connectedness, of caring for multitudes of beings. Take refuge in the care you are generating and the sustenance you are providing, for humans and bees and microorganisms, for gophers and spiders. Our dirty work is good work.”
Ben James describes the day he realized the rusty spots on the right fender of the John Deere he’d recently bought were caused by the palm and fingertips of the previous owner twisting in the seat to see the row behind the tractor. He shares his realization that “Time on the farm is not static, it’s not a given. It’s not like a ladder with all the rungs evenly spaced. Rather it’s a substance, a material we try to manipulate just as much as we do the tilth and fertility of the soil. How many tomatoes can we harvest before the lightning storm arrives?”
Jen Griffith writes about watching the sunset towards the end of her year as an apprentice living in a tent, watching a great blue heron twenty feet away, swallow a gopher whole.
Don’t miss the bonus flip-book in the bottom right page corners. Watch the seed germinate and grow. Use it to distract that young child while you do your accounting! Or for yourself to wind down and cheer up after a hard day.
My annual blogpost of Winter-Kill Temperatures for Cold-Hardy Vegetables is always very popular. In fact, it’s my most popular title! Usually searches for this info increase in October and peak in early November, so here are quick links for those of you who have been meaning to look something up.
For several years, starting in 2012, my friend and neighboring grower Ken Bezilla of Southern Exposure Seed Exchange and I have been keeping records of how well our crops do in the colder season. Ken provided much of the original information, and has suggested the morbidly named Death Bed idea: set aside a small bed and plant a few of each plant in it to audition for winter hardiness. Note each increasingly cold minimum temperature and when the various crops die of cold, to fine-tune your planting for next year (and leave me a comment!) Each year I update the list, based on new things I learned during the recent winter.
We are in zone 7a, with an average annual minimum temperature of 0-5°F (-18°C to -15°C).
The winter 2019-2020 was mild, with our lowest temperature being a single night at 12°F (-11°C). The Koji greens became completely unmarketable but did not completely die. Yukina Savoy is indeed hardier (as I expected), being OK down to 10°F (-12°C). We had one night at 13°F (-10°C) and two each at 17°F (-8°C), 18°F (-8°C also) and 19°F (-7°C). That winter I noted the death of rhubarb stems and leaves at 25°F (-4°C), rather than 22°F (-6°C), as I noted a year or two ago. I also added some cover crop hardiness temperatures.
I also learned that there is more damage when the weather switches suddenly from warm to cold. And that the weatherman in Raleigh, NC says it needs 3 hours at the critical temperature to do damage. Also note that repeated cold temperatures can kill off crops that can survive a single dip to a low temperature, and that cold winds, or cold wet weather can destroy plants quicker than simple cold. All greens do a lot better with row cover to protect them against cold drying winds.
It’s worth noting that in a double-layer hoophouse (8F/5C warmer at night than outside) plants can survive 14F/8C colder than they can outside, without extra rowcover; at least 21F/12C colder than outside with thick rowcover
Salad greens in a hoophouse in zone 7 can survive nights with outdoor lows of 14°F (-10°C). A test year: Lettuce, Mizuna, Turnips, Russian kales, Senposai, Tyee spinach, Tatsoi, Yukina Savoy survived a hoophouse temperature of 10.4°F (-12°C) without rowcover, -2.2°F (-19°C) with. Bright Lights chard got frozen leaf stems.
Seeking Reader Participation
Your experience with your soils, microclimates and rain levels may lead you to use different temperatures. I’d love to hear from readers if they’ve found my numbers work for them, or if they have a different experience. You can leave a comment here, and it will appear on the website, for others to consider. Or you can fill out a Comment Page and only I will see it, although I’ll pass on the information without your name, if I think others would like to know too.
Preparing for Frost and Cold Weather. This post includes our Frost Alert Card, a Frost Predictions checklist of what to do when the first fall frost is expected; how to use sprinklers overnight to stop tomatoes from freezing; four ranges of cold-hardiness (some crops can wait in the garden till it gets colder); and different levels of crop protection, including rowcover, low tunnels, Quick Hoops, caterpillar tunnels and hoophouses (aka high tunnels).
Season Extension and Frost Preparations. This post includes my Season Extension slideshow; the Frost Alert Card and Frost Predictions checklist again; a diagram of our winter double hoop system to hold rowcover in place during the worst weather;
Changing Winter Temperatures
Here’s an article from the Virginia Mercury by Sarah Vogelsong, giving info about changing winter temperatures, particularly later fall frosts in Virginia:
Autumn’s first frost is falling later. For farmers, the consequences are wide-ranging
by Sarah Vogelsong, November 3, 2020
Halloween has come and gone. The clocks have been set back. Every evening darkness falls just a little bit earlier.
But for much of Virginia, the first frost still remains elusive.
Over the past century, the average date of the first frost has been moving progressively backward throughout the commonwealth, today landing a week or more later than it did at the turn of the 20th century.
“This is one of the clearest signs of not only the changing climate but … its impact on our systems,” said Jeremy Hoffman, who as chief scientist at the Science Museum of Virginia conducts extensive research on climate change in Virginia. “It’s not just here, it’s everywhere.”
As global temperatures have warmed, largely due to the release of greenhouse gases into the atmosphere, frost seasons have shrunk. The Fourth National Climate Assessmentreleased by the Trump administration in 2018 reported that “the length of the frost-free season, from the last freeze in spring to the first freeze of autumn, has increased for all regions since the early 1900s.”
How the shifts have played out in different states with different geographic, ecological and topographic features varies. Data from the U.S. Environmental Protection Agency show that between 1895 and 2016, the average date of the first fall frost moved back by 7.1 days in Virginia.
On the local level, the changes may be even starker. Estimates of how much the average date has changed vary depending on the time range used and how scientists fit a line to their data points, but in most Virginia cities, they show unmistakable upward trends. Looking at first frost dates between 1970 and 2016, Climate Central, a nonprofit staffed by scientists and journalists, calculated that on average, the first frost today is 5.9 days later in Lynchburg, 8.9 days later in Harrisonburg, 12.8 days later in Roanoke, 15 days later in Charlottesville and 18.5 days later in Richmond. While their data show Norfolk’s first frost occurring about six days earlier on average, Hoffman said that longer-range data going back to 1940 show the first frost moving back by about five days. Still, he cautioned, variation does occur: “Localized things like weather” can “work against that dominant signal in datasets like these.”
The implications of the shifts in the freezing season go beyond a few more days to enjoy warm weather, say scientists and policymakers. Perhaps most affected are farmers, whose livelihood is intimately tied to fluctuations in both short-term weather and long-term climate.
“Some things you can sort of manage around and some things you can’t,” said Wade Thomason, a professor of crop and soil environmental science at Virginia Tech and the state’s grain crops extension specialist.
For most farmers, the last frost of the year in the spring is the riskier of the season’s two endpoints, falling as it does when most plants are young and more vulnerable to temperature extremes. But ongoing changes in the first frost in the fall also have ripple effects.
“It can be a beneficial thing for some instances. We might get more grazing days for livestock operations in a year,” said Thomason. For some crops, like double-cropped soybeans that are planted following the harvest of another crop — typically a grain like wheat — “it can extend the season.”
Other effects are less immediately apparent. Many wheat farmers who typically plant in mid-October have begun to push back their planting dates to ensure plants don’t grow too quickly during the freezing months, making them susceptible to disease or falling over in the field. Specific types of forage rely on long periods of cool weather to thrive: in Northern Virginia and the Shenandoah Valley, farmers have noticed that orchard-grass stands are only living for four to five years instead of the once-standard 10.
“For years now, we’ve heard from farmers that the stands don’t persist like they used to,” said Thomason. Research has shown that one factor contributing to less persistence is warmer nighttime temperatures, he added, but because most operations rely on cultivars developed decades ago, “we haven’t adapted orchard grass that thrives in a warmer climate.”
Other crops affected by longer warm seasons? Tree fruits and wine grapes
“Virginia’s one of those places that we expect to get hotter and we also expect to get wetter,” said Benjamin Cook, a climate scientist with the National Aeronautics and Space Administration’s Goddard Institute for Space Studies whose research includes the effects of climate change on vineyards. Neither of those conditions are necessarily good for high-quality wine prospects, he said. Furthermore, farmers working in these areas face special risks because of the long time to maturity of their crops.
“Those are parts of the agricultural world that adaptation eventually becomes a lot more challenging, because you can’t switch crops from year to year,” he said. “You have to make a bet on something and wait four years to see if it pays off.”
Regardless of their specialty, all farmers face another consequence of shorter freeze seasons: more weeds and more pests.
“With longer growing seasons, with these warmer winters, the populations of insects are increasing, the mortality is lower, they can produce more generations a year, and that potentially presents a problem for agriculture and plants in general,” said Cook.
Those effects can be seen on the ground, said Thomason: “Maybe 30 years ago, we could stop worrying about them in early October, and now it may be a week or 10 days later.”
Our stories may be republished online or in print under Creative Commons license CC BY-NC-ND 4.0. We ask that you edit only for style or to shorten, provide proper attribution and link to our web site.
I saved this post on Origami Weevils to share. It transitions us from the ridiculous (funny animal videos) to the sublime.
Charley Eiseman describes himself this way: “I am a freelance naturalist, endlessly fascinated by the interconnections of all the living and nonliving things around me. I am the lead author of Tracks & Sign of Insects and Other Invertebrates (Stackpole Books, 2010), and continue to collect photographs and information on this subject. These days I am especially drawn to galls, leaf mines, and other plant-insect interactions.” He is an exceptional photographer, an exceptional entomologist, and one of those people who pays exquisite attention to what he does. These factors make his blog a special treat.
“I always get excited when I encounter the work of leaf-rolling weevils (Attelabidae), even though they are by no means uncommon. I just find it fascinating that these insects have learned to fold leaves into neat little cylindrical packets for their larvae to live inside, without the use of silk or any other adhesive. The […] Read more of this post
Now we might be ready to move off the holiday couch, at least enough to get pencil and paper and start some planning. Here is an EssentialRainwater Harvesting Spreadsheet Toolkit from Verge Permaculture: https://vergepermaculture.ca/product/spreadsheet-tool/ $29.00 CAD (Canadian dollars)
TheEssential Rainwater Harvesting Tool is a spreadsheet tool for analyzingthe feasibility of a rainwater storage system on your farm. It contains tables, formulas and logic from the Verge Essential Rainwater Harvesting book, pre-programmed and ready-to-go, plus a substantial number of extra features.
They are also offering a FREE WEBINAR on Jan 14, 6:30 pm MT: IS RAINWATER SAFE? with pioneering Australian hydrology engineer, economist, policy analyst, educator, UN adviser and researcher Peter Coombes
The National Farmers Union in the United Kingdom has announced in this 12-page report their ambitious goal of reaching net zero greenhouse gas (GHG) emissions across the whole of agriculture in England and Wales by 2040. This is farming’s contribution to the UK’s ambition of net zero by 2050. In the UK, agriculture’s contribution to Greenhouse Gas Emissions is 10% of the nation’s whole. (27% is from transportation)