Weed of the Month for May: Galinsoga

People in early spring weeding spinach that has been hooped and covered overwinter.
Photo Wren Vile

This is the first of my new monthly series of posts. All about weeds.

Sustainable (or Ecological) Weed Management: A Holistic Approach to Organic Weed Management

In the early days of organic farming, maximum use was made of frequent cultivation to kill weeds. Now we know that too-frequent cultivation risks causing soil erosion, and that each tilling or deep hoeing stirs air into the soil and leads to a burning-up of organic matter. The practice of sustainable weed management is about effectiveness – including removing weeds at their most vulnerable stage, or at the last minute before the seed pods explode – and ignoring weeds while they are doing little damage. Work smarter, not harder!

Start with restoring and maintaining balance in the ecosystem. Develop strategies for preventing weeds and for controlling the ones that pop up anyway. An obvious point is to avoid adding new kinds of weeds to any part of your fields. Remove the hitch-hikers from your socks out on the driveway, not when you notice them as you squat to transplant onions! We use our driveway as a convenient place to “roadkill” particularly bad weeds by letting them die in the sun. Beware of Trojan plant swaps!

Weeding in early June. Photo Lori Katz

Weeds are not a monolithic enemy, but a diverse cast of characters. Applying biological principles is not an attitude of war, but more like ju-jitsu, using the weaknesses of the weeds to contribute to their downfall. Develop an understanding of weeds and the different types: annual/perennial; stationary perennials/invasive perennials; cool weather/warm weather; quick-maturing/slow-maturing; and what Chuck Mohler referred to as “Big Bang” versus “Dribblers”. In this monthly blogpost series, we’ll meet various types of weeds, and develop a broader understanding of how and when to tackle each kind.

One factor to consider is how vulnerable the crop is to damage from that weed at that time. Weeds that germinate at the same time as a vegetable crop usually do not really affect the crop’s growth until they become large enough to begin competing for moisture and nutrients. These early weeds have the greatest potential for reducing crop yields if allowed to grow unchecked. We need to cultivate or otherwise control weeds before this 2- to 3-week grace period is over.

Weedy sweet corn. ideally, we would have cultivated two weeks and four weeks after sowing. Photo Bridget Aleshire

The critical period for weed control for the crop is the interval from the end of the initial grace period until the end of the minimum weed-free period, which is approximately the first third to one half of the crop’s life. For vigorous crops like tomato, squash and transplanted brassicas this is four to six weeks; less vigorous crops like onion or carrot need weed-free conditions for eight weeks or more. During that period it is essential to control weeds to prevent loss of yield.

Weeds that emerge later have less effect, and ones that emerge quite late in the crop cycle no longer affect the yield of that crop, although there are long-term reasons for removing weeds to improve future crops.

Know Your Weeds

Lettuce with weeds, easily hoed. Photo Bridget Aleshire

Learn to identify the major weeds on your farm, and any minor ones that suggest trouble later. Observe and research. Start a Weed Log with a page for each weed. Add information about your quarry’s likes and dislikes, habits and possible weak spots. Find out how long the seeds can remain viable under various conditions, and whether there are any dormancy requirements. Note down when it emerges, how soon it forms viable seed (if an annual), when the roots are easiest and hardest to remove from the soil (if a perennial), what time of year it predominates, which plots and which crops have the worst trouble with this weed. Monitor regularly throughout the year, each year. Look back over your records and see if anything you did or didn’t do seems to have made the problem worse or better.

Next think about any vulnerable points in the weed’s growth habit, life cycle, or responses to crops or weather that could provide opportunities for prevention or control. List some promising management options. Try them, record your results, decide what to continue or what to try next.

Most weeds respond well to nutrients, especially nitrogen. If you give corn too much nitrogen, even as compost, the corn productivity will max out and the weeds will use the remaining nutrients. Some crops, like carrots and onions never cast much shade at any point of their growth, so that sun-loving weeds like purslane are more likely to thrive there, but not be a problem for crops which rapidly form canopies that shade the ground.

Galinsoga – a fast growing, fast-seeding weed of cultivated soil.
Photo Wren Vile

Galinsoga

This month’s Weed Character is galinsoga, a “Seed Dribbler”, that matures seed while still quite small plants, sheds some, makes some more, and can carry on for a long seed-shedding season.

Encouraging information is that a constant percentage of the seeds that are still left from one year’s shedding dies each year. This varies widely among species – for lambsquarters it’s 31% per year in cultivated soil (only 8% in uncultivated soil). The number of seeds declines rapidly at first, but a few seeds persist for a long time.

While seeds survive better deeper in the soil, they don’t germinate better down there. Larger seeds can germinate at deeper levels than small seeds. If you are trying to bury seeds deep, use inversion tillage, don’t rely on rotavating, as seeds somehow manage to stay near the surface with rotary tilling. Chuck Mohler, author of the excellent book Manage Weeds on Your Farm, has tested this out with colored plastic beads.

We have two kinds of galinsoga: narrow-leaved and hairy. Both behave the same way. They thrive in highly fertile, freshly tilled soil, just the same as you hope your vegetable seeds will. Mostly we think about how to get rid of galinsoga (prompt hoeing or other cultivation before it flowers), or stop it germinating in the first place (mulches). Its flowers attract beneficial insects such as hoverflies, and it can be eaten by humans and livestock. Young leaves can be used in a soup or in mixed dishes. It doesn’t have a strong flavor. The plants contain flavonoids and phenolic compounds, and it has been found to have antioxidant and anti-inflammatory properties. Extracts from hairy galinsoga can coagulate blood. It is an alternate host for certain nematodes and over twenty insect pests. Hairy galinsoga is thought to have originated in Central and South America, and has become naturalized in North America and other temperate and tropical regions.

Galinsoga is a summer annual that belongs to the sunflower family (Asteraceae) and can invade vegetable gardens with dense infestations that crowd out crop plants. The secrets of galinsoga’s success are that its seeds germinate immediately they reach the soil (no dormancy period), it grows very fast, shading out other plants, it sets seed in as few as 30–40 days after emergence, and continues shedding seed as long as it is growing. It also has the knack of re-rooting if pulled and laid on the surface of the bed, if there is any moisture in the soil. Large plants seem able to transfer the water in their cells to their roots, helping re-rooting happen. Seed that is shed early in the year is capable of growing a mature plant very quickly. There can be multiple generations in one warm season. Fortunately, the seeds are short-lived, and have to be in the top 0.25″ (6mm) of the soil to germinate.

Hoe weeds while they are small and you’ll be rid of those with short-lived seeds in a few years. Galinsoga and Outredgeous lettuce.
Photo Pam Dawling

Galinsoga Identification

Hairy galinsoga (Galinsoga quadriradiata), has profuse hairs on stems and leaves. Narrow-leaved galinsoga ( Galinsoga parvifolia), is very similar, except it is not hairy and it has narrower leaves. Leaves are oval with serrated margins and distinct petioles. They are arranged opposite each other on the stems. The flowers have densely packed yellow disc florets and five tiny white ray florets, each with three scalloped teeth at the end. Seeds of hairy galinsoga germinate between 54°F-86°F (12°C-30°C) with an optimum temperature requirement of 68°F-75°F (20°C-24°C). Most of the seed germination occurs from May to June, after the last frost. It flowers abundantly from about late-May until late fall here in central Virginia. Fallen seeds can germinate immediately due to the absence of dormancy requirement. Take advantage of this phenomenon to eradicate hairy galinsoga from an infested field in three to four years by careful management.

Controls for Galinsoga

Prevention of Weed Germination

Hoeing or mechanical cultivation is effective if carried out repeatedly during the early stages of growth (before flowering). Mulches, such as thick (6-mil) black plastic, or straw, hay, leaves, woodchips over cardboard or newspaper, are effective to control galinsoga in small gardens if applied immediately after planting the crop and before the galinsoga germinates.  Tarping is the equivalent solution for larger areas.

Reduction of Weed Seeding

Grazing, or the mechanical equivalent, mowing, will take care of galinsoga in places you are not currently growing a crop. This weed is not usually found in lawns. It has no resistance to frost. Livestock will happily graze it.

Reduction of Viability of Seeds

Most weed emergence happens within two years of the seeds being shed. Not all seeds that are produced will ever get to germinate (I was very pleased to learn that seeds have many ways of not succeeding!) You can help reduce their chances, by mowing crops immediately after harvest, (to prevent more weed seed formation); then wait before tilling to allow time for seed predators to eat weed seeds that already produced. Seeds lying on or near the soil surface are more likely to deteriorate or become food for seed predators than buried seeds, so delaying tillage generally reduces the number of seeds added to the long-term seed bank. (Short-term, they may germinate!)

If they do not get eaten, dry out or rot, seeds on top of the soil are more likely to germinate than are most buried seeds, and small, short-lived seeds of weeds which have no dormancy period, such as galinsoga, will almost all die within a year or two if they are buried a few inches.

Putting it Together

Strategies include

  1. Inversion tillage such as moldboard plowing (seeds will die off deep in the soil within a year or so.)
  2. Mulching – the seeds will not germinate or be able to grow through the mulch, and will be dead by next year. Be sure to rotate the mulched crops around the farm, so that the benefits are not confined to one section;
  3. Grazing with small livestock, or harvesting galinsoga for human consumption, or mowing: especially mow as soon as the food crops are finished, if you cannot till right away.
  4. Tarping (mow first);
  5. No-till cover crops, with summer crops transplanted into the dying mulch;
  6. Stale seed bed techniques, including flaming;
  7. Plant flowers that attract beneficial insects, particularly seed-eating insects, and birds.
Front cover of manage Weeds on your Farm

Resources on Weeds

Cover Crops in January: The Big Picture

Winter rye and crimson clover cover crop
Photo by McCune Porter

Since May 2023 I have written a post at the beginning of each month about cover crops. In most parts of the US,  January is too late to plant any cover crops, and too early to terminate any  in preparation for sowing(except winter-killed ones!). This is a great time to ponder your cover crop strategies for the coming year, and perhaps plan some changes or tweaks.

I found a great treasure trove of cover crops resources from SARE (Sustainable Agriculture Research and Education). The Resources and Learning tab led me to the Cover Crops Topic and the four page publication Cover Crops for Sustainable Crop Rotations.  

My search for slideshows didn’t immediately turn up the collection I had saved previously, but there is plenty there to usefully inspire you on a rainy day, when you’re all caught up on the accounting and the tool repairs! Or even sooner.

Here’s a compilation of slides I made from SARE’s materials. There are slides on reasons to grow cover crops, some beautiful photos of some good “starter” cover crops, factors to consider when choosing cover crops, information of planting equipment options and opportunities, and several slides of further resources.

Sit back and enjoy the show!

SARE Cover Crops Materials Digest

 

I can also give you to the most recent version I have of my own cover crops slideshow

Cover Crops for Vegetable Growers 2023 60 mins

 

Cover of Managing Cover Crops Profitably book from SARE

Happy New Year , and all the best for a great 2024 growing season!

Book Review The Ecological Farm by Helen Atthowe

Front cover of The Ecological Farm

 The Ecological Farm: A Minimalist No-Till, No-Spray, Selective Weeding, Grow-Your-Own-Fertilizer System of Organic Agriculture, Helen Atthowe, Chelsea Green Publishing, 2023. 368 pages, $44.95.

 In this inspiring book, Helen Atthowe explains her 35 years of experience farming fruit and vegetables in Montana, California and Oregon. This book will appeal to all those (especially orchardists) who are fine-tuning their land management. I think beginners could find it over-whelming, unless they take it in rich small doses! This is definitely a book to dip into and come back to as needed. It provides a Big Picture of ecological farming, not a step-by-step How To.

Helen clearly pays exquisite attention to her farming, conducts research and share her knowledge with others. She operated an Organic orchard in California, together with her husband Carl Rosato, who very sadly died in a farm accident in 2019. Helen and Carl together pioneered ways to raise tree fruit with no pesticides at all. Helen has expertise in ecological weed, disease and pest management, minimal soil disturbance, and managing living mulches, providing soil fertility without manure-based compost, and cultivating habitat for beneficial species. There is lots to learn from this book.

The endorsements for The Ecological Farm are staggering: fifteen well-known ecological farmers (fourteen men and one woman, what’s with that?). Clearly, this work is held in high regard by many experts in the field. The love of farming goes beyond achieving high crop yields, embracing connection with the land and all its forms of life. Helen says “The process of creating farms and gardens opens my eyes to awe, attunes my ears to listening, and offers the gifts of curiosity, discovery and deep connection.”

The ecological approach in this book goes beyond organic, which in the wrong hands simply substitutes a different set of substances for the banned ones, and doesn’t look any deeper. Helen has measured the effects that her actions have had on her land and crops, and shares her results so that we too can grow nutrient-dense foods and leave the environment in a richer, more balanced state than we found it.

The book contains dozens of Helen’s own beautiful full-color photos of plants, pests, birds, fruit trees and vegetables in various combinations. There are prepared forms for monitoring problems and planning interventions. There is a Vegetable Crop Growing and Troubleshooting Guide, a section on Vegetable Crop Insect Pests and Interventions, one on vegetable crop diseases, and similar sections for tree fruit crops.

The first half of the book sets out ten empirical and practical Principles for Managing Ecological Relationships. As the name emphasizes, it’s about managing relationships, not managing crops for highest yields, regardless of what else happens. The connections that form healthy farming ecosystems require us to pay attention, and avoid outside inputs in favor of balancing what is happening on our own farm. There are some excellent charts of applying the ecological principles.

The Principles include creating above- and below-ground diversity; minimizing soil disturbance; maintaining growing roots year-round (living plants secrete 30-60% of the carbon they capture from the air during photosynthesis down into the soil); growing your own carbon; adding organic residues all season; focusing on carbon fertilizers; recycling rather than importing nutrients; fertilizing selectively; weeding selectively; and creating beneficial habitat as close to the crops as possible.

There are many ways to build soil organic matter without removing large quantities of inputs from someone else’s land (not sustainable or fair, as Helen remarks); many ways to build habitat for beneficial organisms; many actions that can steer plants, animals and fungi towards better balance, so that the soil microbial community will thrive and cycle nutrients continuously.

Helen tells that when she started farming, she behaved like a “nitrogen hoarder”, focused on maximizing the amount of nitrogen the soil had available, and topping it up with compost and cover crops if the soil held less than the requirement for the next crop. Her soil management went through a three-stage evolution: She started to view the abundance and diversity of active microbes as the important bit, and the nitrogen level as merely a sign of that activity. Next, she moved to consider the whole soil organic matter system, rather than the parts as separate features to measure. Thirdly, she researched soil carbon and realized that microbially-active carbon was essential fuel for the soil microbes, and deserved more attention.

Actual measurements showed that, contrary to careful calculations, her soil levels of nitrogen, phosphorus and potassium were becoming too high. Helen had been generously adding sheep manure and clover compost at 7-10 tons/acre (18-25 tons/ha). She changed to using mown clover as her main fertilizer, and learned to manage the carbon:nitrogen ratio, with the goal of achieving steady decomposition of organic residues and increased microbe populations and diversity. Simply adding more high-nitrogen material will not provide good crops! We need to build carbon in our soils, and optimize organic matter decomposition and nutrient cycling.

Helen discovered that the C:N ratio of mowed clover living mulch residue varied according to the time of year, being highest (least nitrogen, nodules not yet formed) in July and lowest (most nitrogen, clover flowering) in August and September. This affects nutrient availability and decomposition rate. Vegetable crops do best in Helen’s system if she tills once a year and regularly applies both high-C and low-C residues on the surface. The continuous organic surface residue supply is much better than an annual large dose. Timing when and how we apply organic residues influences their C:N ratio, and hence how we build up carbon in the soil.

Minimizing tillage is another way to build soil organic matter. Incorporated clover releases nitrate-nitrogen into the soil much more quickly than surface-applied cut clover. If your soil has an active and diverse microbial community, incorporating legume cover crops in spring can give a quick burst of nitrogen (for a few weeks), then a sustained regular release of more as it slowly decomposes. With no tillage there is a lag time. No-till does keep the fungal food webs unbroken, which has advantages. It is important to focus on the carbon fertilizers rather than fast-release nitrogen fertilizers. Since 2016, Helen has used only mowed living mulch as fertilizer for most crops, paying close attention to the timing of mowing. The vegetable plots also benefitted from the living mulch in the row middles growing over the bed after the food crop was finished.

I had to look up “row middles” to understand the methods better. With rows of fruit trees, row middles are the aisles between rows of trees. They can be planted in cover crops, which can be mowed and the cut material blown into the tree rows to act as mulch. The photos of vegetable production (other than her home garden) seem to show aisles wider than the beds, so that less than half of the land is in vegetables and more than half is in cover crops. This fits with the method of growing lots of cover crops as the main source of soil fertility. And with Helen’s method of always leaving half of the living mulch row middles unmowed to provide good habitat for beneficial insects. Over here on the East Coast, I am more used to intensive vegetable farms with narrow aisles between beds, perhaps because land is more expensive, perhaps because Bermuda grass is so invasive as to scare off anyone who might consider permanent paths. Jennie Love, a flower farmer in Philadelphia, uses Living Walkways. Hers are 21″ wide, mostly grass and weeds, and require mowing every single week. Helen’s are more focused on legumes, especially clovers.

To focus on a soil organic matter system driven by microbial activity, attention goes to C:N ratios, optimal decomposition speed and nutrient cycling of the cover crops, mulches and composts. As Helen admits, this can be overwhelming, so don’t change everything at once! As you gain experience growing your own fertilizers, you can cut back on imported fertilizers. Do provide a diversity of organic materials throughout the growing season. Having just one kind, all at once is, for the soil, like us eating a whole giant cheese pizza! Soil “indigestion” takes the form of an over-population of just a limited specific microbial community.

Decreasing nutrient inputs and increasing application of organic residues leads to an increase of mycorrhizal fungi. Including chipped woody compost increases the soil carbon. Adding cover crops increases not just the soil nitrogen but also the carbon as more microbial bodies are born, feed and die. Raw organic matter is to be avoided as it acts like an unmanageable surge that can burn plants (by releasing high levels of salts and toxic byproducts) and leach nutrients. In hot humid climates, it is best to aim for slow decomposition to balance the climate’s effect causing fast decomposition. Aim for ten weeks’ worth of nutrients, not more, and watch for foliar signals of nitrogen or phosphorus deficiency that last for more than 3 weeks – a sign that things are out of balance.

In early spring (if early harvest is a priority) you will need to provide easily available nutrients. The first couple of years after switching your focus to carbon, you may be frustrated by the slow rate of decomposition and the lower yields. It takes weeks longer for surface-applied plant matter to release its nutrients than it does for tilled-in plant matter. This requires patience, planning and also has financial implications. Wait 2-4 weeks after incorporating organic residues, or 4-6 weeks after spreading them on the surface, before planting. Animal manure is not essential for soil fertility. After all, animal manure is simply plant matter that has been partially digested. By applying the plant materials to the soil surface, the digestion is done by small soil animals. It’s not so different!

Letting living mulch grow tall in very wet or very hot weather will help dry or cool the soil, but don’t let the cover crop out-compete the food crops for water! Adding cut covers is also a way of adding to soil moisture. Helen is a fan of minimizing tillage, not of banning it.  Tillage decreases organic matter, microbial diversity and abundance, and disrupts the fungal chains. Strip tillage tills out narrow strips to plant into, from an existing sward of cover crops. Tillage incorporates organic residues, adds air, and stirs up a burst of biological activity, helps warm up spring soils, reduces weeds and breaks up compaction. These benefits can be put to use rather than scorned. “Practice tillage with intention” as Helen advises.

Likewise, compost can be useful when starting on poor land, or needing to address some other kind of imbalance. Don’t rule it out completely! There is plenty of information about making good compost here. Did you know the critical temperature for killing most weed seeds is 145˚F (63˚C)? This book also offers a recipe for a liquid fertilizer for “emergency use” on crops showing a nutrient deficiency.

Author Helen Atthowe.
Credit Cindy Haugen

I appreciate reading work by growers such as Helen, who have done the research and experimentation and responded to the science. An average of one page of footnotes per chapter backs up her claims. I’m not a fan of myths and “woo-woo” gardening. This book includes many useful charts and graphs, so you can see the facts. A four-year experiment started with a 50-year old grass, clover, alfalfa and weed pasture, was divided into two fertility treatments. The first was strip-tilled, with the mowed living mulch blown onto the 4′ (1.2 m) wide crop plots each spring. The second was similar, with the addition of 4″ (10 cm) of clover/grass/weed hay mulch in the late summer before the spring strip-tilling. The hay was cut from another field on the farm. Crop yields were economically sustainable in both plots all four years, and there were almost no insect or disease problems. Yields improved in the second and third years. Yields of some crops were higher with the hay addition – peppers and onions significantly; dry beans and cabbage slightly.

The information on choosing cover crops advises using mixes of crops with different C:N ratios, and including legumes whenever possible. This chapter includes recommendations on inoculants, cover crops for various soil types, and “biographies” of four perennials, 15 annuals and the biennial yellow sweet clover.

The book reminds (or informs) us that being able to stop using pest control sprays starts with building the soil, making it comfortable for soil microbes and creating habitat for natural enemies of the pests. The next step is growing healthy plants, by providing optimal conditions of light, temperature and water, and managing plant competition from weeds or over-thick sowing. After that, focus on the balance of nutrients in the soil, especially carbon.

Suppress pests, rather than focusing on killing them. Spraying insecticides, even organic ones, can disrupt balance and leave you inheriting the task of the creatures you killed. Killing all the prey starves the predators who were keeping the prey in check. Learn to intervene with the least possible impact. Tolerate non-threatening amounts of pest damage. Approach in this order: prevention, pest diagnosis, research, monitoring and ecological decision-making. Minimal-impact interventions include trapping and pest-specific microbial insecticides like Bt (which could require ten sprayings to achieve 98% damage-free Brussels sprouts); moderate-impact interventions include broader-spectrum microbials and materials like soap, horticultural oils and minerals; heaviest-impact interventions (those likely to injure non-targets) include using neem oil, pyrethrin, pyrethrum powder and spinosad.

Designing and maintaining a disease-suppressive ecosystem is the title of the section that focuses on preventing diseases. Crop rotations and diversity of crops and other plants are at the top of the list.

Plant competition is the description of the effect of weeds and over-thick planting. We are encouraged to focus on the weeds most likely to cause problems leaving those that can peacefully co-exist with the crop. Knowing and understanding weed ecology is important: when and where does this weed do best? How can you make your vegetable gardens less comfortable for the weed?

Perennial weeds that spread underground need good attention. Helen deals with quack grass, which takes about four years to become a serious invasion problem, when three passes with the tiller 7-10 days apart in spring are needed. I’ve lived with quack grass (couch grass), a cool-weather invasive. It’s a challenge, but I do think the warm-weather Bermuda grass (wire grass) is worse. Tilling also deals with that.

Crop rotations, especially of crops that grow in different seasons, underground crops that need soil disturbance to harvest them, and crops that rapidly cover the soil, are a big help. Helen recommends growing a full-season perennial cover crop on 25-50% of your garden beds or farm area in production each year to break annual weed cycles.

Some cover crops, including cereal rye, hairy vetch, red clover, sunflowers and mustards all exude allellopathic compounds that inhibit germination of nearby seeds (weeds and crops). Often incorporating the cover crop in the soil works better than chop-and-drop, as buried plants decompose without much air, giving a stronger effect. Also tilling reduces the immediate competition from weeds. Tillage can increase yields even if you believe no-till is best! It’s a trade-off. Tillage reduces soil health. Perhaps the sweet spot is minimal tillage, such as strip tillage. Landscape fabric (reused for ten years) offers another method of weed management.

Part Two of the book (approximately half of the pages) covers an ecological approach to crop management and troubleshooting. I didn’t take as many notes of that. After the introduction to some techniques like interplanting, succession planting, making your own microbially-amended seed growing mix, and using season extension tools, the book focuses on thirty popular crops, with tips on crop management, pests and problems.

A tidbit I learned with spinach is that fall-sown plants that reach the two-true-leaf stage before winter will resume growth in late winter. I also learned that the western striped cucumber beetle has a reddish thorax, making it look more like our striped pigweed flea beetle without such sturdy leg muscles.

The crop management sections include soil and fertility needs and special ecological preferences. The problems sections describe symptoms first, then causes, then resistant cultivars and other strategies for avoiding that problem in future. A valuable reference, and good winter browsing when reviewing the season past and preparing for the coming year. The index covers a substantial 18 pages, in three columns, promising to be comprehensive!

Helen Atthowe still acts as advisor to her previous farm, Woodleaf Farm in eastern Oregon, and is a farm consultant in the US and internationally. I notice that Helen is a speaker at the November 2023 Carolina Farm Stewardships Sustainable Farming Conference.

Helen Atthowe, November 2017.
Photo from Veganic World

Workhorse Crops for October

 

The crew working on the sweet potato harvest.
Photo McCune Porter

This is another episode in my monthly series of 14 Workhorse Crops. These crops are reliable under a wide range of conditions. We’re several months into this series, so here’s the complete list: asparagus, beans, cabbage, carrots, chard, collards/kale, garlic, potatoes, sweet corn, sweet potatoes, tomatoes, watermelons, winter squash, zucchini/summer squash.

I hope to help you become more efficient, productive and profitable (if selling) as you deal with another strange year. Maybe you are not at home as much as last year, or maybe your helpers have gone back to school, but you deeply appreciate sustainably grown food.  You still want to garden, even with less time at home. You can use the search box to find previous month’s entries, such as September.

Workhorse Crops to Plant in October

In October in central Virginia we only have enough remaining good growing conditions outdoors to plant 3 of our 14 Workhorse crops – we can still transplant chard, collards and kale. A big step down from last month’s 8. We could also plant some garlic scallions (the soil is still too warm for us to plant garlic, but if you are in a colder zone than us, you’ll want to see this post.)

In October here, outdoor gardening is more focused on harvesting and less on planting. In contrast, October is our busiest planting month in the hoophouse! In September we direct sowed our first hoophouse bed, and sowed other crops in an outdoor nursery seedbed. Two to four weeks later, in October, we transplant them in the hoophouse. Workhorse crops getting transplanted into our hoophouse in October include Red and White Russian Kales, Bright Lights chard, and Napa Chinese cabbage. This year we are trying some carrots (actually we sowed those in September). We have plenty of other crops that don’t qualify as workhorses too!

Chard:

Swiss chard can be sown outdoors here in September, and transplanted early in October for an early winter harvest, with the option of overwintering under rowcover to provide harvests during the winter. We could direct sow chard in September and protect it for the winter, for a late winter and early spring harvest. Remember that red chard is more cold-hardy than the multi-colored types, and green chards tend to be even more hardy.

Hoophouse Bright Lights chard in winter.
Photo Wren Vile

For hoophouse winter harvest, we sow Bright Lights chard in our nursery seedbed September 15 and transplant it October 16. We love the beauty of the multi-colored chard mixes, both growing and after harvest, and we have found that the hoophouse protects the crop well enough that it does not die, even without inner rowcover (unless the outdoor temperature is forecast to be below 8°F (-13°C).

Collards

This is rather late for us to transplant collards outdoors, but if we need to, and we have some good thick rowcover, we’ll do it. The extra warmth of the rowcover will help it make up for lost time.

Kale

Our last date for sowing Vates kale outdoors is 10/30. We can still transplant August-sown kale to fill gaps if we need to – see August’s post. Because kale makes some growth whenever the temperature is above about 40°F (5°C), it is a valuable winter crop. Our sunnier winter days are often warm enough for kale (and spinach!) to make some growth. We will sow more kale in late January, to give us a spring crop.

Red Russian kale in our hoophouse
Photo Pam Dawling

In the hoophouse we grow both the White Russian and the slightly smaller Red Russian kale. See the explanation about the merits of Oleracea and Napus kales. We make sure to transplant the shorter red kale on the south side of the bed, so it gets adequate light, with the white kale on the north. You may have noticed that red and purple-leaved vegetables grow slower and tend to be smaller than their green cousins. This is because they have less green! Green leaves are needed for photosynthesis, which enables plants to grow. Green plants also contain the reds and purples, but the green dominates. This is similar to the conundrum of red and orange fall leaves – where do those colors come from? They are there all along, but are masked by the green. In preparation for leaf fall, the trees absorb all the green chlorophyll, leaving the fall colors visible.

White Russian kale (napus type) gives us good yields in our hoophouse in winter.
Photo Pam Dawling

Garlic scallions

Garlic scallions are immature garlic plants, mostly leaves, pulled up before they make bulbs. They are the garlic equivalent of onion scallions (bunching onions, spring onions, escallions). Great for omelets, stir-fries, pesto, soups, and many other dishes.

We plant ours using the culled tiny cloves from the bulbs we save for outdoor garlic planting in early November. Tiny cloves will never produce big bulbs, so growing garlic scallions makes very good use of them! Planting garlic scallions is simplicity itself! Plant the small cloves close together in closely-spaced furrows, simply dropping the cloves in almost shoulder to shoulder, any way up that they fall. Close the furrow and mulch over the top with spoiled hay or straw.

You could plant these next to your main garlic patch, or in a part of the garden that’s easily accessible for harvest in spring. We plant our small cloves for scallions at one edge of the garden, and as we harvest, we use the weed-free area revealed to sow the lettuce seedlings for that week.

If you want to have Garlic Scallions to eat or sell in early spring, when new fresh vegetables are in short supply, and homesteaders may be running out of stored bulb onions, see my post Alliums for March. With a last frost date of 20–30 April, we harvest garlic scallions March 10 to April 30 in central Virginia, or even into May, if our supply lasts out, and we don’t need the space for something else. Harvesting is simple, although depending on your soil, you may need to loosen the plants with a fork rather than just pulling. Trim the roots, rinse, bundle, set in a small bucket with a little water, and you’re done!

A colorful salad of rainbow chard, onion scallions and garlic scallions.
Photo (and salad) by Bridget Aleshire.

Rather than dig up whole garlic scallion plants, some people cut the greens at 10″ (25 cm) tall and bunch them, allowing cuts to be made every two or three weeks. We tried this, but prefer to simply lift the whole plant once it reaches about 7″–8″ (18–20 cm). The leaves keep in better condition if still attached to the clove. Scallions can be sold in small bunches of three to six depending on size. A little goes a long way! If you do have more than you can sell in the spring, you could chop and dry them, or make pesto for sale later in the year.

You can plant garlic scallions at other times of year, if you have planting material. See Plant garlic scallions from softneck varieties (Alliums for February). If you plant in a hoophouse, more of the year opens up as a planting season. You can plant whole bulbs (the small cull ones you can’t sell, or don’t want to peel) and grow your garlic scallions already in a clump, rather than in rows of plants.

Some growers find they make more money from garlic scallions than from bulb garlic, partly because they don’t have the costs of curing and drying the bulbs! I encourage you to experiment with planting a few cloves at different times of year and record your results. Because you do not need to work with the right times for bulbing and drying down, all sorts of dates are possible!

Napa Chinese cabbage

Maybe you think I’m stretching things to classify Napa Chinese cabbage as a workhorse, but in my defense, I’ll say firstly that success in farming involves creativity and flexibility, and secondly that the Asian greens as a category are genuine Hoophouse Workhorses, as they grow so well in cool temperatures and short days. It is a cabbage! We sow Blues (53d from transplanting in mild weather) in a nursery seedbed on September 15 and transplant in the hoophouse October 2, at only two weeks old (very fast-growing in September). Because this is a heading vegetable, we leave it to grow to full size before harvesting. That will be in January. Many of the Asian Greens are harvested by the leaf, but Napa cabbage and pak choy are more often cut as a head.

Young Chinese cabbage transplants in our hoophouse.
Photo by Bridget Aleshire

Workhorse Crops to Harvest in October

Eleven of our 14 workhorse crops can be harvested in October (also true in September and August, but with substitutions!) No asparagus, no garlic, no more watermelon. Depending when the frost bites, there will be several fewer harvest options by the end of October.

Beans­ can be harvested until the weather gets too cold. We have covered the beds with rowcover to keep the plants warmer and growing faster. It’s true that pollinating insects can’t get at the flowers to perform their pollination services and make more beans, etc. But that doesn’t matter. We are more interested in fattening up the already pollinated beans! It’s also true that the yields are now way down, so we need to balance the benefits against the costs. Sometimes it is better to clear the crop (and its pests and diseases) and sow a cover crop.

Cabbage We harvest fall planted cabbage from September 25. We like Early Jersey Wakefield (45 days from transplanting) and Farao (64d) for fast-maturing cabbage; Melissa Savoy 85d; Early Flat Dutch 85d, Kaitlin 94d, for storage cabbage which are slower-growing. We have also liked huge Tribute 103d, Tendersweet (71d) for immediate fall use, and Wakamine (70d). Deadon (105d winter cabbage) is extremely cold hardy – we leave it outdoors until nights threaten to hit 10°F (-12°C) . Double-check those days to maturity, I may have mixed days from transplanting with days from sowing.

Deadon cabbage
Credit Johnnys Selected Seeds

Carrots: If we sowed carrots in July, we will be harvesting in October.

Chard can be harvested whenever you want some. This year our chard did extremely well all summer and we are bored silly with it! We wish we had had stored cabbage, or some fall broccoli. We are relishing our fall senposai!

The outdoor killing temperature for unprotected Bright Lights chard is 22°F (–6°C); red chard survives down to 15°F (–9.5°C) and green chard to 10°F (–12°C).

Collards can be harvested in October.

Kale can be lightly harvested, if our early August sowings came through.

Potatoes: We can plant potatoes between mid-March and mid-June, leading to harvests in July-October. Protect potatoes from frost when harvesting. Read more about potato harvest here.

Our March-planted potatoes are in the root cellar. We’ve been eating those since July. We often plan to grow more in the June planting than the March planting, as root cellar storage over the summer is more challenging for us than having them in the ground.

Sweet Corn harvest is still going, thanks to our sixth sowing on July 16.

Sweet Potato harvest at Twin Oaks. Photo McCune Porter

Sweet potatoes need harvesting in October here, before it gets too cold. Usually sweet potatoes are harvested the week the first frost typically occurs. I wrote a lot about this topic here. I wrote all the harvesting details in another post, 10/12/20.

Contrary to myth, there is no toxin that moves from frozen leaves down into the roots. On the other hand, below 55°F (13°C), they’ll get chilling injury, which can ruin the crop. Roots without leaf cover after a frost are exposed to cold air temperatures, and have lost their method of pulling water up out of the soil. I remember one awful year when we left the sweet potatoes in the ground too late, hoping they’d fatten up a bit to make up for a poor growing season. Instead, the weather got cold and wet, and the sweet potatoes were rotting in the ground (it was November by then), and those that didn’t rot got chilling damage that prevented them ever softening in cooking. Sweet potatoes that stay hard are no fun to eat!

Tomatoes are winding down. If a frost threatens we will harvest them all, including the green ones. I prefer to store them on egg trays or in shallow crates, to gradually ripen indoors. But other people prefer fried green tomatoes. To my taste buds, it could be cardboard inside the batter! I don’t know the nutrient content of fried green tomatoes, but I feel certain ripened tomatoes without batter are more nutritious!

Winter Squash harvest continues once a week throughout September and October. Stored winter squash can provide meals all winter and also in early spring when other crops are scarce. We used to harvest as late as possible in the fall, but now we prioritize getting a good cover crop established, to replenish and protect the soil, so we have a Grand Finale harvest just before Halloween, when we harvest all the large interesting almost-ripe squash, and give them away for lantern carving. Some go to the chickens too. Harvest before the fruits get frosted, which is shown by a water-soaked appearance of the skin.

Zucchini and summer squash are now being harvested every other day. Our last sowing was August 5. We harvest beyond the first fall frost, by covering that last planting with rowcover on chilly nights. But once it gets cooler, they grow slower, and are not worth checking every day.

From storage: spring cabbage, carrots, garlic and potatoes, winter squash.

Food processing is still busy.

Workhorse Crops Special Topic

Winter rye and crimson clover cover crop
Photo by McCune Porter

Cover Crops

September 17 is our last chance to sow oats as a cover crop. If sown later they will not reach a good size before they are killed by cold temperatures. The soil would not be held together well. It would be better in those circumstances to mow the weeds and leave their roots to hold the soil together over the winter.

Oats winter-kill in most of zone 7 or colder, and survive in zone 8 or warmer. The end for oats is around 10°F (-12°C), depending on their size and the frequency of cold temperatures. Large oat plants winter-kill after 3 days at 20°F (-7°C) or colder. Young oats are tolerant to temperatures down to 12°F (-11°C), until the 5 leaf stage, as the growing point is still underground. Once the plant starts to make noticeable vertical growth and form nodes (22-36 days after planting, depending on variety, sowing date, and water), oats can die at 24°F (-4°C).

Dead oats leave an easy-to-work surface for early spring vegetables.

Clovers can be sown here throughout September, as can winter wheat and winter barley. Winter rye can be sown here in September (not August – it could head up!). Hardy Austrian winter peas can be sown in late September with rye.

For more details, see my post Planning Winter Cover Crops

August 2021 Sustainable Farming News Roundup

Fredericksburg Food Co-op, https://fredericksburgfood.coop/  320 Jefferson Davis Hwy, Fredericksburg VA 22401. Phone: (540) 940-6615 Tuesday August 24, Time: 6-7 pm

Fredericksburg Food Coop

Fall Vegetable Production

60 min Discussion and Q and A This is a conversation, not a powerpoint, and will be held outdoors on the dining patio. There will be handouts with lots of resources for more information.

My books will be available for sale and signing. Bring your old dog-eared copies, I’m very happy to sign those too!


Seven Springs Fair

Mother Earth News Fair at Seven Springs, Pennsylvania 

(September 17-19, 2021)  The in-person fair is going to be cancelled.

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See the Events page for workshops in October, November, January and onwards.

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Harvest to Table has a list of August Vegetable Garden tasks, if you need that. I can always find some useful tips on this site.

Harvest to Table logo

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For gardeners in central Virginia, the Piedmont Master Gardeners monthly Garden Shed newsletter offers August in the Edible Garden by Ralph Morini, and The Nutritional Value of Leafy Green Vegetables by Penny Fenner-Crisp (including a good resource list), and several other topics. Each newsletter has a photo of a different garden shed. Here’s this month’s (with hammock!)

Piedmont Master Gardeners Shed newsletter. (Some sheds have a hammock!)

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Future Harvest Beginning Farmer Training Program

For the next scale up, beginning farmers in the Chesapeake region can apply to Future Harvest’s Beginner Farmer Training Program (BFTP)  I have the honor of being one of their Level 3 consultants.

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Organic Growers School logo

Organic Growers School, based in Asheville, North Carolina, is also open for applicants for their Journeyperson program and their year-long Farm Beginnings program

Journeyperson Program is for those who have been farming for 3 years and are looking to grow a farm business. Join Nicole DelCogliano, August 26th, at 7 pm for a Journeyperson Info Session. via Instagram Live! Nicole will answer your questions about our Year-Long Journeyperson program, (which starts in November 2021 and ends in October 2022), and discuss options to meet your farming needs. 

 

Organic Growers School Farm Beginnings Program

Farm Beginnings is a year-long training program, including Whole Farm & enterprise
planning,  Connection to a farmer network, Growing season learning plan, On-Farm Field days & workshops. This is for those who have already considered making a career of farming, and have taken some steps in that direction. Deadline for this year is September 18. Click the title link and watch the video.

There are also field days, skill sessions, work exchanges, internships and the Farm Dreams program for those at an earlier stage of the process. To help you choose, click Growing the Next Generation of Farmers, and check out this worksheet.

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SARE logo

Following on from my recent post about planning winter cover crops, here’s something else useful: SARE has a new video “Cover Crops and Soil Health” which illustrates how producers can use cover crops to improve productivity and sustainability. In just a few short minutes, “Cover Crops and Soil Health” outlines how cover crops can build soil structure, protect water quality, suppress pests and improve a farm’s bottom line.

Combining cover crops and reduced tillage can also help farmers:

  • Manage soil nutrients
  • Reduce erosion and compaction
  • Improve water holding capacity and infiltration
  • Reduce input costs
  • Increase yields

“Cover Crops and Soil Health” is now available for viewing and sharing at www.sare.org and on YouTube. Farmers, ranchers, educators and other agricultural professionals may download or embed the video without modification into websites or other noncommercial educational presentations. The entire “What is Sustainable Agriculture” series is also available on YouTube. This video series was produced through a collaboration of the Sustainable Agriculture Research and Education (SARE) program and Pixeldust Studios.

Crimson clover cover crop starting to flower.
Photo Kathryn Simmons

Book Review: The Living Soil Handbook by Jesse Frost

Cover of The Living Soil Handbook by Jesse Frost

The Living Soil Handbook

The No-Till Grower’s Guide to Ecological Market Gardening, by Jesse Frost, Chelsea Green Publishers, July 2021. 304 pages, $29.95

Jesse Frost, the host of Farmer Jesse’s No-Till Market Garden Podcast, has now made a lovely how-to and why-to book for us. No longer do we need to imagine the pictures while listening to the podcasts! The book is generously illustrated with color photos, charts, and diagrams and also hand drawings by Jesse’s wife Hannah Crabtree. The text and photos make plain the experience behind the suggestions. A glance at the bibliography shows how deeply Jesse educated himself on soil biology, chemistry and physics – it’s a list of detailed articles, not a list of books. I was interviewed by Jesse’s collaborator Josh Sattin for Farmer Jesse’s podcast, in November 2019.

Jesse and Hannah farm at Rough Draft Farmstead in central Kentucky, winter hardiness zone 6b with 55” (140 cm) of annual rain on average. While writing the book, Hannah and Jesse moved farms, gaining road frontage for on-farm sales!

The book revolves on three basic principles of professional no-till market gardening: disturbing the soil as little as possible, keeping soil covered as much as possible, and keeping it planted as much as possible. The phrase “as possible” in each of the three principles remind us to be reasonable, and aware of the context. No-dogma is as important as no-soil-disturbance. Sometimes a short-term soil disturbance will ultimately create a healthier soil: you might need to incorporate compost or amendments, or break up compaction. We are not feeding the plants. Nor the soil. We are farming the micro-livestock.

Appendices include notes on cover crops (when to sow, what to pair each cover crop with and how to terminate it); valuable material on critical periods of competition (for weeds or interplanting); resources and chapter notes from world-wide sources.

The topics have been carefully teased apart and the chapters are digestible by busy farmers during the growing season. No need to wait until winter! There are things you can do in midseason to head in the direction of less tilling and more soil-nurturing.

The first section, “Disturb as Little as Possible” includes a fine primer on the science of living soil. (Now you can explain photosynthesis to an inquisitive child.) Don’t skip over this basic soil science. Understanding is the key to good stewardship. The carbon cycle includes plants absorbing carbon dioxide, making root exudates that stream out into the soil, where they feed microbes, which respire most of it back into the air. The plants are not sequestering carbon, as we might wistfully hope in these days of an overheating planet. They are cycling it. It is true that some of the carbon that plants pass into the soil does remain there, in the tissue and exoskeletons of dead organisms, especially when there is no tillage. Some carbon converts to a stable form holding soil particles together.

Most growers probably know that frequent rototilling damages the soil (especially at the same depth every time, or when the soil is too wet or too dry). Soil care can include disturbance of various human kinds. Silage tarps can cause compaction when they gather rain, snow or ice, and stay in place a long time. Microplastic particles can crumble off old tarps into the soil, where they can be eaten up by the microfauna. Polyethylene can prevent beneficial gas exchange between the soil and the air. The soil life also “disturbs” the soil, churning it. Be guided by your observations of your soil, not by a particular belief in a certain method.

The chapter on breaking new ground describes several ways to make a no-till garden from a lawn, pasture or old garden. Deal with any soil compaction up front, either mechanically, or with an extra growing season and big-rooted plants.

Start with the no-till methods Jesse and Hannah use most often. “Shallow compost mulching” involves keeping a 4” (10 cm) layer (not deeper) on bed surfaces year-round, topping up as needed. With a 4” layer, the roots can reach the soil quite soon. Their second preferred method is grown-in-place mulch. Terminate a thick stand of cover crop and plant into the mulch as soon as it has wilted down.

If you don’t need to till before starting your vegetables, you can mow at soil level, and cover with a tarp for two summer months or 3-5 winter months. If you are mowing in the fall, you could spread cardboard and compost to form the beds, then tarp everything until spring.

Silage tarps and plastic mulches can be particularly helpful during transition, to salvage beds when things go wrong, or as emergency tools when a mulch supply line collapses.

The second section, “Keep it Covered as Much as Possible”, discusses compost, mulch, cover crops, flipping beds (transitioning from one crop to the next) and path management.

Composts come in four types (recipes included):compost

  1. Inoculating composts are expensive, fine textured and biologically active. Vermicast (worm manure) is one example. Good for compost tea.
  2. Fertilizing composts such as composted poultry manure are fine textured nitrogen sources to use before planting.
  3. Nutritional composts supply organic matter, microbiology, nutrients, minerals, and ample amounts of carbonaceous material. They can be used in larger amounts.
  4. Mulching composts are high in carbon, maybe 20 C:1 N, and relatively low in nutrients.

Mulching retains moisture, prevents compaction, reduces weeds, provides habitat, provides foods for some creatures, and reduces the impact of heavy rain or heavy feet. Straw can be expensive. Hay gives better weed suppression, but may itself be a source of weed seed. Spoiled hay has fewer live seeds, comes at a better price, and is messier to spread. Hay is more nutritious for the soil than straw. You could solarize your hay bales for 3-8 weeks before spreading, to kill seeds.

Paper and cardboard give excellent occultation compared to loose straw and hay, and provide an effective mulch with less depth (easier for transplanting into).

Wood chips, sawdust and bark mulch can sometimes be free, from workers clearing under power lines. Tree leaves and leaf mold are nutritious materials for mulch or in compost. Cover crops may be mowed or crimped to kill them, usually leaving them in place as a newly-dead mulch.

Peat moss is controversial. Peat bogs are very effective carbon sequestering habitats, and based on this, we should not use peat without restoring the bogs. Coconut coir is sometimes used as an alternative to peat moss, but we are mining the thin tropical soils when we import it.

Plastic mulches stop weeds, warm the soil, and conserve moisture. Landscape fabric is durable, and some growers burn holes for transplanting certain crops, and reuse it many times. Organic regulations require plastic mulch to be taken up at the end of the growing season, and they do not accept biodegradable plastic mulches.

Jesse Frost

Chapter Five is about flipping beds (replacing one crop with the next). Chopping plants off at the surface and/or tarping are two main no-till methods.

Jesse provides a valuable table of no-till crop termination methods for 48 vegetables and herbs. Whenever possible, leave the crop roots in the soil. Some can be cut at the surface (lettuce, baby greens, cucurbits and nightshades), some need to be cut slightly below the surface (brassicas, beans, corn, spinach and chard) and most others are harvested as root crops. Roots are a valuable source of carbon and root exudates, and help air and water pass through the soil.

Flail mowers, weed whackers (with a bush blade rather than a nylon line), scythes, hoes and knives can all be used to cut down old crops, depending on the particulars. When a crop is terrminated, deal with soil compaction if needed, amend the soil, keep it damp, get mulch in place, and replant the same day if you can, to help preserve microbes. If the previous crop was a cover crop, your fertility is supplied by that, and no more amendments are likely needed.

Tarping (introduced into English by Jean-Martin Fortier as “occultation”) is an effective no-till method. Silage tarps can kill crop residues, warm the soil and germinate weed seeds, which then die in the dark. Prepare an area by mowing it close – it is important that the tarp is in close contact with the soil, to break the plant matter down quickly. Tarps need to be well battened down. Jesse tells us that 2600 square feet (242 m2) is about as big a piece as any one person will want to move.  Say, a 25 x 100ft (8 x 30 m) piece.

Leave tarps in place for two summer weeks, 3-4 weeks in spring and fall, and two months or more in winter. Avoid PVC tarps (contain endocrine-disrupting phthalates), be wary of polyethylene (may contain phthalates), but woven landscape fabrics are made from polypropylene, which does not contain phthalates.

Solarizing is a similar technique using clear plastic to heat the soil, kill weed seeds, disease organisms and crop residues. Bryan O’Hara in No-Till Intensive Vegetable Culture has popularized using old hoophouse plastic. Solarizing can produce temperatures of 125˚F (50˚C) compared with 110˚F (43˚C) under tarps. You may need only 1-3 sunny days to kill crop residues with solarization. Cover crops take about 7 days. The heat will not go deep in that time: more of the soil life will survive than with tarping. Good edge securing is vital for success.

The necessary (but less profitable) task of path management is next. The goal is to make pathways do work, retaining moisture, housing microbes, and generally contributing to a healthy environment. The first priority is to get rid of weeds.

Wood chips and sawdust can perform well as path mulches. Sawdust mats down into an effective weed-preventing layer, and 2” (5 cm) is often enough. Get sawdust in place ahead of leafy greens, so that it doesn’t blow into the crop.

Living pathways sound wonderful, but can be very challenging, and it’s best to start with a small trial. Choose a non-spreading grass or a mix of clovers, grasses and herbs. Mow every week until the path plants stop growing.

Another option is to grow cover crops in the paths, mow-kill or winter-kill them and leave the mulch in place. Timing is critical. The crop needs to be planted and harvested either before the cover cop grows very tall or after it is dead.

Section three, “Keep it Planted as Much as Possible” has three chapters: fertility management, transplanting and interplanting, and a gallery of no-till crops, pulling together various materials and methods.

Test soil organic matter each year. Jesse points out that although organic matter is largely dead organic materials, a truly living soil must contain a fair amount of it! 5-10% OM is a healthy percentage; more is not better. OM above 12% can cause water retention problems and poor aggregation. Seedlings can struggle to germinate and establish.

You can improve soil performance with compost, mulches, cover crops, gypsum for clay soils, and cultivated indigenous microorganisms (as in Korean Natural Farming). Use good inoculating compost or compost tea in the root zone. Microbes aggregate the soil into various sizes of crumbs, improving the soil structure.

Be careful using perennial cover crops as living mulch around cash crops – the yield is almost always reduced, and sometimes the quality is compromised too.

If you are running a compact commercial market garden, growing cover crops may be out of the question, and you will rely on outside inputs. With a slightly bigger plot you can grow cover crops before long-season food crops, and use outside inputs for intensive short-term crops. Larger farms may find cover cropping more efficient than large-scale mulching. Winter-kill, classically with oats and spring peas sown in late summer, will provide a light mulch for early spring crops.

Cover crops can be terminated by crimping at the milk stage and tarping. Jesse shows a crimping tool made from a bed-width board with a foot-sized metal hoop at each end and a string or rod as a handle. This is a variation on the T-post tool advocated by Daniel Mays in The No-Till Organic Vegetable Farm.

Crimping and tarping gives more flexibility on timing than does crimping alone. Crimping and solarizing can be even quicker. Crimping or mowing, then topping with cardboard and mulch compost is another method, if you have sufficient supplies. Plant a shallow-rooted crop in the compost layer, don’t bust through the cardboard unless you have let the cover crop die for a few days before covering.

For side-dressing long-season crops, Jesse uses the EarthWay seeder with the pea plate. This never occurred to me! Another surprise suggestion was to use silage tarps white side up, to germinate carrots in the summer! Check daily, and remove the tarp late in the day to save the tender seedlings from frying in the mid-day sun.

Interplanting is best approached cautiously, with small trials and good notetaking. Interplanting can cause lower yields and poorer plant health when combinations and timing are wrong. Measure yields and weigh the costs and benefits. Popping lettuces into random lettuce-sized gaps rarely goes wrong, and you might keep a tray of lettuce transplants handy at all times.

Peppers take 60-70 days before bringing in any money. If you plant an understory of lettuce, you can generate income much sooner, and the lettuce will be gone before the peppers need the space. Growing two crops together reduces the impact of a crop failure, and makes unprofitable crops more worthwhile.

Read about the critical period of weed control, when crops are most affected by competition from weeds, sister seedlings or an intercrop. Like other good mentors, Jesse is quite open about his mistakes. Don’t confuse tall plants with healthy high-yielding plants! They may be striving for better light. Seedlings suffer more than transplants from being out-shaded. Transplants are past perhaps half of their critical weed-free period before you even set them out.

Relay cropping is a method of adding in another crop after the first is established but before it is harvested. A sure-fire way of keeping living roots in the ground! With careful planning you can sometimes run a multi-crop relay sequence.

To implant these ideas firmly in our minds, Jesse discusses seven example crops, including varieties, seed quantities, bed prep, weed control, seeder, spacing, pest control, harvest, yield, intercrops, marketing, tips, and notable failures (no need to make the same mistakes!). The examples (carrots, arugula, garlic, lettuce, sweet potatoes, beets, and cherry tomatoes) can be extrapolated for almost anything else. I took notes: there’s always good tips to be learned from other growers. Buy the book, you’ll quickly save the price! And more of your growing can succeed!

I originally wrote this review for the upcoming June/July 2021 issue of Growing for Market magazine.

Forget Miami peas; Forget industrial hemp; Optimize your Asian greens

Forget Miami peas

For years I have been mentioning “Miami Peas” in my presentations about cover crops. At the Carolina Farm Stewardship conference I was asked what they are, by Mark Schonbeck, who knows cover crops well. (This is one of the wonderful benefits of attending conferences – meeting peers and mentors, and learning new things.)
I said it is a frost tender cover crop pea of the field pea type (not a southern pea). I can’t remember where I first heard about this cover crop, and we haven’t been using it on our farm, so it was time for a reality check when I got home. I can’t find any reference to Miami peas apart from the ones I’ve made! I believe it’s a type of Canadian field pea, but maybe it no longer goes by the Miami name, or maybe it never did! It’s embarrassing to promote untruths.
Spring forage peas from Seven Springs Farm, Virginia

Pinetree Seeds says:

This short term green manure smothers weeds well and adds nitrogen and other nutrients to the soil. Peas are often mixed with vetch, oats, or rye as an effective cover crop. The sprouts are delicious and you can even harvest the peas themselves for soup. This annual prefers cool well drained soil and has no frost tolerance. Sow 3 to 4 lbs per 1000 sq. ft.

For clarity, here’s what I now believe:
  • “Forage pea” and “Field pea” are terms that include the  hardy Austrian winter peas, that we do use and are big fans of, as well as frost-tender spring peas, also known as Canadian field peas.
  • Canadian field peas are not frost tolerant and are sold by Pinetree Seeds. among others.
  • SARE lists Canadian field peas as Spring Peas. SARE is a very reliable source of information. They say

These annual “spring peas” can outgrow spring-planted winter peas. They often are seeded with triticale or another small grain. Spring peas have larger seeds, so there are fewer seeds per pound and seeding rates are higher, about 100 to 160 lb./A. However, spring pea seed is a bit less expensive than Austrian winter pea seed. TRAPPER is the most common Canadian field pea cultivar.

  • Other spring pea varieties are Dundale and Arvika
  • There’s also a tropical Pigeon Pea, Cajanus cajan, which can grow in the Southern US, but that looks pretty different, and I don’t think that’s what I meant.
Pigeon Pea flowers, Cajanus cajan
Photo Wikipedia

 

Forget industrial hemp

I have been alarmed at how many small-scale growers are trying industrial hemp. Partly I’m hoping it won’t cause a shortage in locally grown food! I also wonder how well an industrial field crop grows on a small scale, and how the growers would deal with the permits, the processing and the marketing.

Read this report from The Modern Farmer about how industrial hemp is unsuccessful for most growers and how the market is swamped with would-be suppliers:

Thousands Began Farming Hemp This Year. It Hasn’t Gone How They Hoped.

Optimize your Asian greens production

Here’s my updated slideshow on Asian greens, which I presented at the Carolina Farm Stewardship conference. 

Check their website for details about other workshop sessions too. I believe my handouts, and those of other speakers, will soon be available on their website.

Click the diagonal arrow symbol to view this full screen., and click the forward arrow to start viewing.

Senposai is our star of Asian greens. Here’s a bed of senposai outdoors in spring.
Photo Kathryn Simmons

Conferences and Cover Crops

Conferences

I have had a little flurry of arranging workshops, so if you have (educational) travel plans, check out my Events page. I’ve also got two interviews lined up, for podcasts, and I’ll tell you about those when they go online.

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This coming weekend (Thursday October 31 to Sunday November 3) I will be at the Carolina Farm Stewardship Association Sustainable Agriculture ConferenceSheraton Imperial Hotel and Convention Center, Durham, North Carolina.

In the full day 8.30 am- 4.30 pm Pre-Conference intensive Advanced Organic Management, on Friday Nov 1, from 8.45-9.45 am in the Empire ballroom D, I will be presenting a 60 min workshop:

A cover crop mix of winter rye, hairy vetch and crimson clover.
Credit Kathryn Simmons

Cover Crops for Vegetable Growers

Use cover crops to feed and improve the soil, smother weeds, and prevent soil erosion. Select cover crops to make use of opportunities year round: early spring, summer, fall and going into winter. Fit cover crops into the schedule of vegetable production while maintaining a healthy crop rotation.

 In the Main Conference, on Sat Nov 2, 1.30 – 2.45 pm in the Empire Ballroom E, I have a 75 min workshop

Yukina Savoy
Photo Wren Vile

Optimize your Asian Greens Production

This workshop covers the production of Asian greens outdoors and in hoop houses in detail, for both market and home growers. Grow many varieties of tasty, nutritious greens easily and quickly, and bring fast returns. The workshop includes tips on variety selection of over twenty types of Asian greens; timing of plantings including succession planting when appropriate; crop rotation in the hoop house; pest and disease management; fertility; weed management and harvesting.

 I will be participating in the Booksigning on Saturday 5.45 – 6.45 pm during the reception

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Crimson clover is a beautiful and useful cover crop.
Photo Kathryn Simmons

Winter Cover Crops

 

Cover crops have been much on my mind. Partly it’s that time of year – too late for us to sow oats, not so late that the only option left is winter rye. Here’s my handy-dandy visual aid for central Virginia and other areas of cold-hardiness zone 7a with similar climates.

If you are considering growing winter rye as a no-till cover crop this winter, check out this video:

Rye Termination Timing: When to Successfully Crimp, by Mark Dempsey

“Interested in no-till production, but unsure of how to manage cover crops so they don’t become a problem for the crop that follows?

The most common management concern is when to crimp your cover crop to get a good kill but prevent it from setting seed. Getting the timing right on crimping small grain cover crops like rye isn’t difficult, but it does take a little attention to its growth stage. See this three-minute video for a quick run-down on which stages to look for in order to get that timing right.”

https://www.youtube.com/watch?v=loKPRLdAUXw

 

Sustainable Market Farming on sale.
Photo Ken Bezilla

A good cover crop resource is my book Sustainable Market Farming, which has 9 pages of detailed charts and a nine page chapter of cover crop info.

 

 

Managing Cover Crops Profitably from  SARE is the book with the most information.

What can you do if spring is too wet?

Our kale beds after heavy rain. Photo Wren Vile

As growers, we do not have control over everything that happens. The main thing outside of our control is the weather, and it’s only going to get more chaotic as climate change bites. Heavy rain events can leave soil impossible to work, because the water can’t drain away fast enough. What can we do when it’s too wet?

Laura Lengnick in Resilient Agriculture views climate change as yet another production risk to assess and prepare for. The vulnerability of your farm has two components: exposure and adaptive capacity. As far as exposure, the most immediate key exposure is water issues (too much and too little). As for adaptive capacity, the main feature is our personal capacity to respond and plan. We need to pay greater attention to the climate as a critical factor in our decision-making.

Be Prepared

  • See Weatherspark.com for easy-to-understand graphics showing the average weather in your locality. Figure out which crops are most marginal already in your climate, and decide whether they are worth keeping in your crop portfolio, and whether they are important enough to be worth providing more protection for.
  • Using raised beds can help excess water to drain sooner.
  • Raised beds will drain and be ready to plant sooner after rain.
    Photo Ezra Freeman
  • Increasing the organic matter content of the soil helps it absorb more water in a manageable way, without compacting and going anaerobic. Compost improves the soil structure, organic matter and humus. The effects last longer than cover crops and crop residues, especially in humid conditions where the breakdown of plant material is very rapid.
  • Maximize the volume of living roots (food crops and cover crops) throughout the soil profile (use both deep-rooted and shallow-rooted crops).
  • Cover crops. The root channels improve the soil structure — fine roots make up 70% of the root biomass of crimson clover, vetches, and field peas, and when the cover crops are mowed, these roots support microbial growth, form active organic matter, and rapidly release N to the plants. Keeping roots in the soil all the time, or as much of the time as possible, will help prevent erosion.
  • Consider no-till cover crops which become mulch.

    A no-till cover crop mix of winter rye, hairy vetch, Austrian winter peas and crimson clover.
    Photo Bridget Aleshire
  • Avoid “bare fallow” at times of year when you could get a lot of rain. That might mean not just hurricane season, but year-round. Low-growing non-invasive cover crops can be planted in pathways.
  • Minimize tillage because tilling accelerates nutrient burn-up and hence the loss of organic matter. Avoid tilling or disking right before a forecast of heavy rain.
  • If water drainage is a big issue where you are, you may need to consider a “grassed waterway” Your NRCS office can help with the design. See their publication Grassed Waterway and Vegetated Filter System, Conservation Practice Job Sheet 412. This is really a very large gradual swale with a grassed surface, which you can mow (think home-grown mulch!).
  • Another option is a “drywell” or French drain, a big hole full of rock. We calculated that for our hoophouse, ours would need to be 11′ × 11′ (3.4 × 3.4 m) and 4′ (1.2 m) deep. It would have been a big area and a lot of rock (and money), and not inconsiderable maintenance to keep it free of sediment and leaves.
  • Field tile drainage
  • Keyline plowing (along contours).
  • Swales (also called “infiltration trenches”) allow water to gradually seep into the soil, while sending sudden large volumes downhill to an area which can absorb more water. A swale 18″ (45 cm) wide by 8″ (20 cm) deep in averagely draining soil can infiltrate approximately 1.6″ (4 cm) rain per hour per 20 ft2 (1.86 m2) of contributing area.

    A caterpillar tunnel and a plastic mulched bed at Potomac vegetable Farms in November.
    Photo Pam Dawling
  • Physically cover the soil: hoophouses and caterpillar tunnels can help keep crops from deluges. Large structures do have the issue of runoff, but you can plan ahead for that and make a drainage system. When we built our hoophouse, we made a ditch around three sides of it, to channel runoff downhill. Some people who have roll-up or drop-down sidewalls install plastic guttering on the “hipwall” lumber that these structures need, and collect the rainwater for irrigation. Bear in mind that the water catchment barrel will be low down and the water will need pumping or dipping and hauling to be useful. Read the NRCS Code 558 Roof Runoff Structure.
  • Before the storm moves in, cover the soil where you plan to plant: temporary caterpillar tunnels (field houses), low tunnels, plastic mulches and tarping (occultation) can keep some of the soil dry, at the expense of causing runoff that makes other areas wetter. This can help get crucial plantings done in a timely way, leaving the wider problem to resolve later.
Fast-growing Red Salad Bowl lettuce.
Photo Bridget Aleshire

First Aid if you can’t plant when you want to

  • Consider transplanting instead of direct seeding. We did this one year with our winter squash, when the plot was hopelessly too wet. We were able to transplant the squash fairly young, and did not have a big harvest delay.
  • Consider a different, faster, variety that you can sow later and catch up. Some leaf lettuces only need 46 days (Salad Bowl, Bronze Arrowhead, Tom Thumb), while Romaines can take a lot longer (Crisp Mint, Winter Wonderland 70 days, Webb’s Wonderful 72 days). Baby lettuce mix can be ready in as little as 21 days from mid-spring to mid-fall.
  • Consider a different, faster, crop that you can sow or transplant later. Keep your crop rotation in mind, as well as the next crop you intended to plant in that spot. Here are some fast-growing crops:
    • Ready in 30–35 days are some Brassicas such as kale, arugula, radishes (both the fast small ones and the larger winter ones); many Asian greens (Chinese Napa cabbage, Komatsuna, Maruba Santoh, mizuna, pak choy, Senposai (40 days) tatsoi, Tokyo Bekana and Yukina Savoy). See my Asian Greens of the Month category of posts
    • One summer we sowed Tokyo Bekana as a lettuce substitute. 20 days to baby size, 45 days to a (large) full size.
    • Also ready in 30–35 days are spinach, chard, salad greens (lettuce, endives, chicories) and winter purslane.
    • Ready in 35–45 days are corn salad, land cress, sorrel, parsley and chervil.
    • Ready in 60 days are beets, collards, kohlrabi, turnips and small fast cabbages (Farao or Early Jersey Wakefield).
  • The International Cooperators’ Guide Grafting Tomatoes for Production in the Hot-Wet Season recommends using eggplant rootstocks for tomatoes when flooding is expected.

First Aid if you can’t till

  • Could you mow? This will prevent weeds seeding, and prevent the cover crop or previous food crop from getting any bigger. It will be easier to till once that does become possible.
  • If you can’t get a mower across the beds, can you use a weed whip (string trimmer) or a manual weed whacker or a scythe? This will buy you some time.
  • Could you use a broadfork? This will open up the soil, allowing it to dry faster.
  • Could you lay tarps over the whole mess, and wait for the cover crop or weeds to die?
  • Could you use a flame weeder to kill the existing vegetation? Flamers are intended to kill small weeds, not big ones, but we successfully used our wand-type flamer to kill weeds in the potato patch one spring when it was too wet to hill the potatoes.
Flaming (pre-emergent)
Photo Brittany Lewis

Dealing with Floods

  • If your soil floods, drain it promptly, or you may end up with drowned plants (insufficient air) and with a high salt level caused by evaporation. Dig shallow trenches to let the flood water flow away.
  • After the flood recedes, you could lose yield from loss of soluble nutrients. The soil may have become anaerobic, reducing available nitrogen. If you have a suitable source of nitrogen, apply some. You may also get a flush of weeds, competing with your slow-to-recover crop.
  • See How to Rehab Your Soil after a Flood on the Hobby Farms website for five steps to repairing the damage: Clean Up, Remove Water, Beware of Contamination, Level the Land, Rebuild the Soil with Cover Crops. See also the Carolina Farm Stewardship Association’s Expert Tip: How to Handle Flooded Fields for information about food safety.
  • Consult your local Extension service before selling any produce that has been in standing water, as the water may have become contaminated. See the US Food and Drug Administration Guidance for Industry: Evaluating the Safety of Flood-Affected Food Crops for Human Consumption
  • There is more about dealing with floods  and disasters in general, in The Year-Round Hoophouse.

Washing tomato seeds, Heritage Harvest Festival, Organic Broadcaster

Wet Roma tomato seeds set to dry with a fan.
Photo Pam Dawling

Last week I wrote about saving tomato seeds and eating the tomatoes too. We left the extracted tomato seed in a bucket to ferment for three days. On Friday I washed the seeds. They look quite unappetizing at first, with a thin layer of mold on the surface of the liquid.

Roma tomato seed ferment on day 3, ready for washing.
Photo Pam Dawling

The process of washing the seeds and pouring off the detritus is almost magical. The fermentation kills some disease spores, and also dissolves the gel that coats the seeds. If you dry tomato seeds without fermenting, they all stick together.

Tomato seed processing: adding water from a hose and stirring the mix.
Photo Pam Dawling

With each successive wash, more of the tomato flesh floats off, along with poor quality seeds. I add water using a hose and stir. Here I’m stirring with a short length of green plastic pipe that was conveniently nearby. When the bucket is about two-thirds full I turn off the hose and stop stirring. Good seed sinks to the bottom of the bucket. When I think it has settled, I pour the liquid along with lumps of tomato flesh into another bucket. This is a safety precaution to ensure I don’t throw away good seed. If I just poured it on the ground I could slip and dump the lot.

Roma tomato seed ferment after first pour.
Photo Pam Dawling

I repeat the wash and pour a few more times. Even after the second pour the seeds are plainly visible.

Roma tomato seed ferment after the second pour.
Photo Pam Dawling

The seeds which float and get poured away are very light and are either very thin or they show a black spot in the center. So it’s counter-productive to try to catch every single seed.Let the useless seeds float away!

Tomato seed extraction after the third pour.
Photo Pam Dawling

After four or five washes the water I pour off is clear, so then I add more water, stir and pour the swirling stuff through a sieve balanced on a bucket.

Tomato seed extraction, fourth wash water. almost clear.
Photo Pam Dawling

In my case I have a small sieve balanced in a bigger one, which sits more safely on the bucket, but has a mesh too big for tomato seeds. This sieve contains seed from 10 gallons of Roma tomatoes.

Roma tomato seeds strained in a sieve.
Photo Pam Dawling

From here, I take the seed sieve indoors and empty it on sturdy paper towels on a tray by a small fan. See the first photo. After a few hours I come by and crumble the clumps of seeds to help even out the drying. For two days I turn the seeds over a few times a day. Once they are dry I put them in a labelled paper bag, and ready the space for the next batch of seeds to dry. Watermelon in this case. I alternate tomato and watermelon seeds, processing one batch of each every week through late July to early September.


Heritage Harvest Festival

I mentioned the Heritage Harvest Festival a few weeks ago. I’m presenting one of the Premium Workshops on Friday, about growing sweet potatoes. See my Events Page for more about this. Pictures of sweet potatoes at this time of year are a monotonous swath of green leaves (now we have got a double electric fence to stop the deer eating the leaves off.) Last year we didn’t do a good job of keeping deer off our sweet potatoes and we got low yields. One of our gardening mantras is “Never make the same mistake two years running!” so you can be sure we are working hard to keep the pesky deer from eating our winter food.

On Saturday September 9, I’ll be out and about at the Festival, and hope to see many old friends and make some new ones.

If you live in North Carolina and can’t make it all the way to Virginia for the Heritage Harvest Festival at Monticello, you could go to the Organic Growers School Harvest Conference that same weekend September 8-9. I’ve been to their Spring Conference several times, but never the Harvest Conference because it’s always the same weekend as the Heritage Harvest Festival.


Photo courtesy of Organic Broadcaster and MOSES

The July/August issue of Organic Broadcaster has been on my desk for a few weeks waiting for time to read it. This newspaper is free online, with a new issue every two months. It covers more aspects of Organic Farming than simply vegetable production. There are good articles about cover crops, including roller-crimping no-till rye. Also an article on weed control for market farmers by Bailey Webster, who interviewed farmers and researchers. Harriet Behar, the senior organic specialist at MOSES, write about the thorny issues of falsely labeled Organic foods: imported livestock feedstuffs, milk from cows with no pasture access and algal oil in Organic milk. Now that 68% of Americans bought organic foods of some kind (Pew), more Organic suppliers are needed to meet the demand (or else the unscrupulous rush in with false labels.) There are further articles about cash flow for farmers, winter bale grazing for cattle, the 2018 Farm Bill, and transferring the farm to new owners.

Now we are getting some rain from Cyclone 10, which might have become Tropical Storm Irma, but now looks less likely to qualify for a name. But, enough rain to want to stay indoors, so maybe I can read for a while.