Nematode-resistant food crops and cover crops

Golden Frills and Scarlet Frills, two Juncea mustards that resist nematodes. Photo Pam Dawling

A few weeks ago I wrote about clearing tomato plants, and mentioned our hoophouse troubles with nematodes. Nematodes are tiny soil-dwelling worms that have a wide host range and are hard to control. They move only 3’–4′ (1–1.2 m) per year on their own, but people move them on shoes, tools, etc. We have had peanut root-knot nematodes (Meloidogyne arenaria) since 2011 when we found them in spinach transplants we were growing for outdoors in early spring.

My article on nematodes in Growing for Market  in November 2014 describes our discovery of the beasties and our first attempts to deal with them.

White Russian kale in our hoophouse.
Photo Pam Dawling

In my August 2014 post Good news – great hoeing weather! Bad news – more nematodes in the hoophouse I wrote about solarization to fight nematodes in our hoophouse (scroll down to the end of the post). The post includes a photo of our first attempt at solarizing – a  bit of a How Not To! Be sure to use UV-inhibited polyethylene. This year we somehow got some construction plastic mixed in. It doesn’t work! It goes cloudy (thus not heating up the soil) and it shatters into little pieces.

There is info on dealing with nematodes from Garry Ross in Hawaii, where nematodes are a fact of daily life, in my post Cold weather, snow, thinking about nematodes from February 2015.

My most thorough blogpost about nematodes was in 2018 for Mother Earth News:  Managing Nematodes in the Hoophouse.

Solarizing with clear plastic. Photo Pam Dawling

My post Solarization and crop choices to fight nematodes in August 2019 includes a photo of a much better way to solarize an individual bed. In that post I gave a list of nematode-resistant food crops, and also talked about cover crops. There is a photo of nematodes on cucumber roots there too).

Food crop choices to fight nematodes

Most resistant and most helpful are the Juncea group of mustards. I did some research into more Juncea options in Solarization and crop choices to fight nematodes. We don’t like very pungent greens, so we have not yet taken the route of planting a whole bed of Juncea types. Instead we have mapped and flagged the nematode-infested areas of our beds, and try to be mindful of what we plant in those spots. Three of our seven beds have no nematodes so far.

Open-pollinated Yukina Savoy.
Photo Ethan Hirsh

This year we looked at the nematode map we had made and decided to focus our attention on the bed with the highest number of nematode patches, and grow the most resistant winter crops (of the ones we like to grow) there. That’s the frilly mustards (Ruby Streaks, Scarlet Frills, Golden Frills, all Juncea mustards, and Mizuna, a Japonica mustard), Yukina Savoy (variously reported to be Brassica juncea,  Brassica rapa pekinensis, and Brassica rapa), and Russian kales (Brassica rapa).

Mapping nematode areas

See the post with info from Gerry Ross I mentioned above. We have previously tried for a “Two years good, One year bad” strategy. This was to grow nematode-resistant crops in the infected areas for two years, then try risking one year of susceptible crops. That was a bit demanding on careful management, and we haven’t kept that up.

Nematode map 2022

Cover crop choices to fight nematodes

French marigolds and sesame to deter Root Knot nematodes in our hoophouse. Photo Pam Dawling

A reader asked about cover crop choices to fight nematodes. In June 2019 I wrote about using marigolds, sesame, Iron and Clay cowpeas as warm-weather nematode resistant cover crops. We’ve also used winter wheat (in winter!), and white lupins (not worthwhile, in my experience). See that post for a few other ideas on nematode-fighting cover crops, and why we decided against some options. At that time, we decided not to grow sunnhemp (Crotolaria) because it is poisonous, although newer varieties of Crotolaria have lower toxin levels. More recently we have been growing sunnhemp, after I saw it growing so well in North Carolina. It is a warm-weather legume, so it is feeding the soil while tackling the nematodes. It does grow tall in the hoophouse, and we have taken to chopping it down with hedge shears to an ergonomic elbow-height every few weeks whenever it gets too tall. The cut tops create a nice “forest-floor” mulch effect. You can almost feel the extra organic matter nurturing the soil! (High OM levels deter nematodes.) 60-90 days to maturity.

Sunnhemp cover crop at Nourishing Acres Farm, NC.
Photo Pam Dawling

We previously used soybeans as a short-term leguminous summer cover crop, but they do not offer the nematode resistance. Iron and Clay, Mississippi Silver and Carolina Crowder cowpeas are all nematode-resistant and can be grown in summer instead of soybeans. Sesame is a legume that is particularly good against peanut root-knot nematodes.

Iron and Clay southern peas flowering in September. Photo Pam Dawling

See Our Organic Integrated Pest Management post for an organized approach to pest management, including nematodes.

A Florida reader gave me information about partridge peas, which I have not yet tried: After terminating cool-season brassicas and celery between April and June, their late spring sowing of partridge peas were too late this year to be productive, because the hard seed was very slow to germinate. Partridge pea could be a good cover crop for mid- to late-summer, if you scarify those hard seeds to speed germination.

Some cover crops can be alternate hosts for pathogens like cercospora, rust, or bacterial leaf spot, so be on the lookout for new problems while solving old problems. In the deep south, beans, yard-long (asparagus) beans, and cowpeas can succumb to heat, nematodes, rust, bacterial spots, and other pathogens and pests. Senna (tall) and Partridge pea can provide “chop-and-drop” organic matter as sunnhemp does. Sunn Hemp can host foliar pathogens (some possibly seed-borne), in Florida, and does not reliably form nitrogen-fixing nodules on the roots, even when inoculated. Even so, it is useful as a fast warm season green manure cover.

The flower Gaillardia (blanket flower) is a quick-to-compost, chop and drop option for late winter to late spring, It decomposes quickly, and can provide a quick green manure. Gaillardia is nematode-resistant, great for beneficials and pollinators, but is susceptible to some foliar pathogens later in the season. You can sow Gaillardia in August, or even later in fall for early spring flowering.

Due to climate change, and the more year-round activity of nematodes, pathogens, and pests in Florida, they’ve been including more nematode-resistant grasses into their rotations. We all need to be thinking more about warmer-climate options, as climate change continues to push pathogens and pests farther north, earlier each year.

Farmer and gardener health and wellness

A crew member string-weaving peas in our hoophouse in February. Photo Wren Vile

Raising food is good work, right livelihood, outdoor work in the rain, sunshine and fresh air. The physical tiredness at the end of the day can bring good sleep. Farmers contribute to production of healthy food, and get to enjoy extremely fresh food from very local farms.

And yet – some days this is not the whole story. Farming can be hard on the body, the brain and the emotions. It can be stressful trying to get a good outcome from a situation that went outside our control and took a turn for the worse. Some things we can control, others we cannot. Some things we will be able to do a better job of dealing with next time they come around. Our work is not punching out identical widgets. Seasons change, tasks change. Only for a short time each year do we need to know how to decide if a watermelon is ripe. Once in a hundred years we need to know how to deal with a one-hundred-year flood (hmm!). I have written about being prepared for and dealing with disasters in The Year-Round Hoophouse. Being prepared and having a plan of what to do when things go wrong is a very good way to manage mental and emotional stress.

Hauling sweet potatoes uphill the hard way. Sometimes we use the truck!
Photo Nina Gentle

Musculoskeletal health

First let’s talk about physical health of the musculoskeletal kind. Overdoing the hard work, making the wrong move, going beyond the limits of our bodies, and wow! Pain! Maybe even injury. After many repeats of the same action, inflammation and problems such as carpal tunnel syndrome, and over time, maybe arthritis too. Musculoskeletal pain affects bones, joints, ligaments, tendons or muscles. See the Cleveland Clinic information page.

Common symptoms include aching, stiffness, burning sensations in the muscles, fatigue, muscle twitches, pain that worsens with movement and sleep disturbances.

Home treatment can include hot and cold compresses, over-the-counter pain relievers (NSAIDs), strengthening and conditioning exercises, stretching exercises, and stress reduction techniques.

Professional treatments can include local injections with anesthetic or anti-inflammatory medications, physical or occupational therapy, acupuncture or acupressure and relaxation/ biofeedback techniques. Most people I’ve seen at physical therapy are there for sports injuries. Sports medicine offers many good exercises for people whose work has injured their bodies.

Prevention is definitely better than cure. I’m a firm believer in doing some stretches and strengthening exercises every morning. Yoga is great too. Going to the gym? Some farmers make time for this, others don’t. Here’s some more prevention tips: limit repetitive movements, or vary them, use good posture and practice correct lifting techniques. (I recommend the Alexander Technique). Alexander Technique teachers help you identify and change harmful habits of posture and body use, and learn to move more freely.

I have written some articles in Growing for Market magazine that are accessible for those with a Full Access subscription on the website. I wrote about stretching in April 2008. Julie Bradley Law wrote an article: A wintertime reset for our most important tool: our bodies. It is free to access, and recommends a few weeks of winter rest, yoga and attunement. Designed by a farmer.

AgrAbility Tool Box

For those with limited physical abilities, AgrAbility provides Assistive Technology, Resources, News, Training, Services in your State. The Toolbox: Agricultural Tools, Equipment, Machinery & Buildings for Farmers and Ranchers with Physical Disabilities is a resource that contains assistive technology solutions for farmers, ranchers, and other agricultural workers with disabilities.

Physical illness

Remember to get checkups. Be aware of ticks, mosquitoes, and rodents and the pest-borne illnesses they can cause. Read about Public health issues caused by pests. The EPA, the Centers for Disease Control and Prevention (CDC), and the U.S. Department of Agriculture (USDA) have collaborated to create a thorough List of Pests of Significant Public Health Importance

Pests and diseases and climate change: as the climate chaos intensifies pests will move into new geographical ranges. We need to learn about the Zika virus, (cases in Florida and Texas in 2016-17, but none in the continental US since then). Chikungunya is another mosquito-borne virus. In 2014 and 2015, a few local-transmission chikungunya virus disease cases were found in Florida, Texas, Puerto Rico and the U.S. Virgin Islands. Most of the cases in the US are travelers returning from countries where the disease is endemic.

Internal physical trouble

Let’s keep in mind the symptoms and treatment of heat stress. Heat stress happens when your body can’t cool itself enough. Physical activity during very hot, humid weather, and insufficient replacement of water and electrolytes cause heat stress. It can lead to heatstroke, which is a serious, life-threatening condition.

Home-made rehydration solution

Here is our recipe (“salty lemonade”):

  • 8 oz water
  • 8oz fruit juice (or mix concentrated lemon juice to usual lemonade strength)
  • A pinch (1/8 tsp) salt
  • 2 pinches (¼ tsp) baking soda

During watermelon season, a plate-sized slice of watermelon seems to do the trick!

Crimson Sweet Virginia Select watermelon.
Credit Southern Exposure Seed Exchange

At the other end of the risky weather is extreme cold, especially if it is wet and windy. Livestock farmers are more at risk of hypothermia, trying to save their animals under terrible conditions. Vegetable farmers don’t suffer the same degree of risk.

Our lungs are vulnerable to dusts, pollen, sprays, toxins, microbial pests like the Coronavirus, flu, prions (mad cow disease) and anthrax.. Good masks can guard against all these, as well as asthma and allergies. There are also some specific agricultural problems like farmers’ lung, an allergic disease usually caused by breathing in the dust from moldy hay, or other moldy crop.

Mesothelioma

You may remember hearing about problems with vermiculite in some potting mixes. Some vermiculite naturally includes asbestos. Farmers are at risk of exposure to asbestos through contaminated soil, vermiculite and dust from these products on farm equipment. The Mesothelioma Center provides free information: books, packets and a Patient Advocacy program that works with people individually to help them find local treatment, legal help, and support groups. If you may have been exposed to asbestos they help you find free care and support. They will send you a free printed guide to mesothelioma. Sign up at their website.

Mesothelioma Info pack

The site has a special section for farmers: Farmers and Asbestos.

Mental health

New Mental Health Resources for Farmers in Stressful Times

by Matt Kneece, CFSA South Carolina Policy Coordinator Aug. 5, 2022

“However rewarding, the farming lifestyle often brings a compounding mental load that can be difficult to deal with. Fortunately, the stigmas around mental health and farm stress are breaking down, and farmers don’t have to deal with it alone. . . There are loads of resources to support producers’ physical health, but programs to support mental health are just as critical.”

South Carolina Farm Bureau is now offering access to a new program called AgriWellness including three online counseling sessions free of charge.

North Carolina Agromedicine Institute has compiled a list of resources here.

Another great resource is available through Rural Advancement Foundation International – USA, which offers a crisis hotline for farmers. When crises begin piling up, one of the most important things farmers can do is reach out for help as soon as possible. RAFI-USA’s hotline is designed to be a type of rapid-response available for farmers who need to talk to someone on short notice.

“Farming is a challenging job that can easily be impacted by factors beyond farmers’ control,” said Lisa Misch of RAFI-USA. “Anything from crop failure, natural disasters, market price changes, or family emergencies could lead to a farm crisis. If you are in crisis and need someone to talk to, please call toll-free at (866) 586-6746. The hotline is open Monday through Friday from 9 a.m. to 6 p.m.ET” They also provide in-depth assistance from a farmer advocate if you are in danger of losing your farm and/or home.

“In addition to the new therapeutic resources featured above, mental health experts have recommended several tips to farmers dealing with farm stress. Pursuing a healthy diet, staying active, cultivating social support, and getting enough sleep are all great steps toward protecting your mental health.”

I hope you will never need it, but if you get to that point, call the National Suicide Prevention Hotline at 1-800-273-TALK (8255) or 1-800-799-4889 (deaf/hard of hearing) or text 741741 to the Crisis Text Line.

New 988 Suicide and Crisis Lifeline. Dial just 988. Available 24 hours. English or Spanish. Learn more The 988 Suicide & Crisis Lifeline is a United States-based suicide prevention network of over 160 crisis centers that provides 24/7 service via a toll-free hotline with the number 9-8-8. It is available to anyone in suicidal crisis or emotional distress.

Veterans Crisis Line
https://www.veteranscrisisline.net/
1-800-273-TALK (8255), press ‘1’ Text 838255 Chat also available

The American Foundation for Suicide Prevention has info on warning signs, how to have a conversation with a loved one you are concerned about, suicide loss, and more.

SC Farm Stress Management Resource Guide

I’ll leave you with this Clemson University Cooperative Extension Service link to Farm Stress Management Resources. There are educational resources, worksheets, articles, podcasts, links to support organizations, and other stress management websites.

I also took part in an interview with Jordan Marr for a podcast with The Ruminant: Audio Candy for Farmers, Gardeners and Food Lovers. It’s about farmers’ struggles with mental health problems, trying to cope with the many and varied stresses, while the public wants farmers to appear competent and blissful with all that time in the Inspiring and Nurturing Outdoors.

The Farmers Aren’t All Right. Podcast from the Ruminant. Episode 92.

Facebookhttps://www.facebook.com/theruminant/posts/1369936529736669

Clearing Tomato Plants

These tomato plants have served us well, and their time is up. We have pulled them out of the ground and left them suspended in the twine to wilt, before hauling them to the compost pile. The bed behind the tomatoes is being solarized to kill fungal lettuce diseases. Photo Pam Dawling

Here in Virginia, we pull up our two beds of tomatoes in the hoophouse at the very end of July or early in August. I realize this will horrify people in colder climates. I’ve been there. Every tomato plant was to be cherished until the frost took it. But in hot, humid Virginia, we have harvested from these plants for nine weeks, and the outdoor plants are coming in strongly. We don’t need the hoophouse ones; they’ve grown taller than we can reach, and we’ve lopped the tops off with hedge shears several times. Fungal diseases are to be reckoned with, and we only manage a two-year rotation in each bed, as far as nightshades go. In the past, we grew “high summer” food crops or seed crops, and needed to get the tomatoes out to make way for the new crops. Nowadays we only grow cover crops in the summer, until it’s time to prepare the beds for fall planting.

String-weaving diagram from Extension.org

We use the Florida String Weaving method of supporting our tomatoes. One thing I like about this method is that it is easy to take down, and all you have to store for next year are the stakes, which take less space than cages, or individual T-posts. We have a descriptive list of steps, and also a Worksheet – see below.

Another feature of our life with our hoophouse tomatoes are the Peanut Root-Knot Nematodes. When we pull our tomatoes, we examine the roots and carefully remove the ones with nematode lumps in them, usually to the parking lot on a dry sunny day, to die in the heat and be run over by cars. We don’t even want to send them to the landfill, because we don’t want to do anything that increases the number of nematodes anywhere. Nematodes need a film of water to survive, and the parking lot deprives them of that.

Cucumber roots with nematodes (see circles). We forgot to take photos of the tomato roots.
Photo Pam Dawling

We spread the tomato clearance job out over a week, doing one step each day, so we don’t have to be in the hoophouse after 11 am, when the temperature becomes unbearable. After harvesting all the fruit (ripe and unripe, separately) in the first bed, we pull up the plants and check the roots. If we see nematode lumps, we carefully cut off the roots and take them outside. We mark the area with a blue flag in each corner, and later measure the distance from the end of the bed and mark the problem area on a map of the beds. This is in case the flags mysteriously fall out.

When we plan the winter crops, we plant the more nematode-resistant crops in the infested areas.With the non-nematode infected plants (most of them) we shake the soil off the roots to speed up the wilting. Plus of course, we don’t want to be removing precious topsoil from the hoophouse! We leave all the plants still hanging in place in the rows of twine, to dry out for a couple of days. We are going to haul them to the compost pile, and it’s a lot less work (fewer cartloads) once the plants have wilted.

Cutting down through the layers of twine in preparation for clearing string-woven tomatoes. Photo Pam Dawling

The second day, we collect up the plant labels and put them in either the “Successes” bucket or the “Failures” bucket according to whether we want to grow that variety again. We cut the twine, pull out the long pieces and collect them in a trash bucket. We don’t try to save the twine, partly because it would take a lot of time, and partly because we don’t want to use twine that might be infected with fungal diseases. The easy way to remove the twine is simply to cut downwards beside a stake, through each of the pieces of twine, then go to the next stake and do the same, but this time gather the twine in the non-knife hand. Next, slice down the other side of the same stake, to reduce struggle, and make the lengths of twine easy to pull out! We use sisal twine, so we let the small pieces, which were wrapped around the stakes, drop to the ground. Most of them will get collected up when we pull the stakes, and a few will go with the plants to the compost pile.

Gathering the lengths of twine after cutting at both sides of each tomato stake. Photo Pam Dawling
Tomato clearance, after cutting and pulling the twine, and removing the stake extenders in the near bed. The bed to the right still has the extenders in place. Photo Pam Dawling

The third day we pull up the stakes. To reach the full height we needed, we have tied an extension stake onto each one, so first we remove those, then we pull the stakes that are in the ground. We like to use a T-post puller for this job, as it gets the wood posts out nicely without breaking them off in the ground. We only use the wood stakes for hoophouse tomatoes once, and the next year we use them outdoors, often for the snap peas. This is to reduce spread of diseases. When we pull out the metal T-posts we scrape the soil off, then spray them down and scrub with a brush.

Our (welding-repaired) T-post puller makes fast effective work of removing wood stakes too. 15 seconds per stake.
Photo Pam Dawling
When I’m collecting things togethe, I throw them into clusters as I work, and make them ready to move easily. Photo Pam Dawling

The fourth day we haul the wilted plants to the compost pile. We make a little effort to keep the zipper spiders in the hoophouse, but they have minds of their own! We do gather up any egg cases we see, and hang those on the metal framework of the hoophouse, to provide spiders next year.

A large zipper spider in our hoophouse in early August. Photo Pam Dawling
Zipper spider egg cases overwintering in our hoophouse.
Photo Wren Vile

On day 5 we rake and (if in time) sow a summer cover crop. We like to use soy as a warm weather legume that will supply some nitrogen, but it needs 6 weeks to be worthwhile. If we are a bit late, we’ll just sow buckwheat. We need our first bed for fall and winter crops on September 6. The others won’t be needed until Early October or later.

The steps for the second bed happen one day later than they happen in the first one. See the worksheet to get the full story.

Hoophouse Tomato Clearing Worksheet

If you live in a cooler climate than I do and you want to learn about keeping tomato plants growing (and accessible) in a hoophouse, read Andrew Mefferd’s book The Greenhouse and Hoophouse Grower’s Handbook. There he explains the lower and lean method of supporting tomato vines.

And I’ll close out with this photo which shows a tomato stem that I accidentally broke when doing the first round of stringweaving. I bandaged it back together with electrical tape from our drip tape first aid box. In the past I have also repaired stems with band aids. It works really well and the plants recover to live a normal productive life.

Yes, this really works! Tomato stem repaired with electrical tape 5 months earlier.
Photo Pam Dawling

Caring for your Okra Crop

 

Carmine Splendor okra plant.
Photo Pam Dawling

Okra is a long season crop, so cultivation or mulch to keep weeds down will be needed. We hoe until hot weather arrives and then mulch with spoiled hay (avoid using organic mulches earlier in the season, as they keep the soil cool and delay the harvest). During the rest of the growing season, the okra bed becomes a useful repository for any undiseased mulch-like materials from other beds, even quite large plants like sunflowers.

Okra has a great ability to withstand drought compared to other vegetables, but for good growth and production, you’ll need to water at least 1” (2.5 cm) a week. If there is an extended dry period and you can’t water everything, okra will be the last to suffer.

Okra bed in June.
Photo Pam Dawling

Catching up

See Okra Planting Time for info on varieties, crop requirements, yield, sowing, transplanting, intercropping, and Chris Smith’s wonderful book The Whole Okra. However, if you haven’t sown your okra seed yet, time is of the essence. Okra needs 55-60 days of hot weather to produce the crop. If you are in the deep South, go ahead!

Black plastic mulch, rowcovers and transplanting can all help get the crop going earlier, as can growing in a hoophouse or caterpillar tunnel, if you are a real fan of okra. The yield per area is low, so this would be an unusual choice for the prime real estate offered by a hoophouse!

Our first Cow Horn okra pod, in late June.
Photo Pam Dawling

In Sweet corn, potatoes and okra, I reported that we started harvesting our okra that year a little later than it might have been because we had to replant. The first planting had leggy seedlings due to not enough light soon enough in their lives. Then we transplanted replacements with novice helpers, and they didn’t plant them deep enough. The feeble stems couldn’t take it. We made an attempt to hill them up to give more protection to the stems. Another mistake we made was over-watering. When we pulled up some of the dead plants for our postmortem, they reminded me of retted flax stems – the fibers were still there, with the soft tissue rotted away.

Succession Planting and Renovating Okra Plants

Generally only one planting of okra is made each year, although it is possible to sow in spring and fall in hot climates, using a fast-maturing variety for the later sowing. Or sow only in the summer for a fall crop, and don’t fight cold spring soil temperatures.

In hot climates, okra plants benefit from being rejuvenated in the middle of the summer, by cutting them back (with a machete, or tree loppers) to 6” (15 cm) stubs after the first heavy harvest (perhaps in the fifth week of harvesting) and after market prices start to decline. For large areas, use a tractor mower.

The plants will produce again in the fall, when prices have risen again, and fall yields can be higher than spring crops. Side-dressing at this stage can also boost production. As well as revitalizing the productivity, this process keeps the plants at a manageable height.

Alternatively, to avoid losing all your crop at once, lop progressively along the row, perhaps cutting 5% of the plants each day, starting after they reach shoulder height. Other growers tell of cutting back plants to a height of 4’ (1.2 m), which causes the plant to branch more.

Rotations

Okra is about the easiest vegetable to fit into a rotation as you are unlikely to have any other mallow-family crops to worry about, and you are unlikely to be growing a huge amount. Cotton, hibiscus and the fiber plant kenaf are also in the mallow family, but do not cross-pollinate with okra.

Pests and Diseases

Okra has few serious pests or diseases, if the weather is warm. In cool weather, stressed okra plants may suffer from verticillium and fusarium wilts, soil-borne diseases that cause plants to wilt and die. Fight soil-borne diseases by avoiding soil splashing onto the plants – use drip irrigation and mulch. Foliage blights may occur, but generally they do not reach serious levels. Blossom blight can be a problem in long rainy periods.

Old varieties of okra tend to have deeper root systems and are more tolerant of root-knot nematode, to which okra is very susceptible. If you have nematodes, choose heirloom varieties. Okra will do fine after grains, such as sweet corn, or following a winter rye cover crop.

Corn Earworm larvae come in many different colors. And they can bite!
(Photo: J. Obermeyer Purdue Extension)

Insect pests may include Japanese beetles, stink bugs, aphids, corn earworms, flea beetles, blister beetles and cucumber beetles. You may see ants climbing the plants to drink nectar but they don’t seem to cause damage. Grasshoppers may strip the leaves in late summer in bad grasshopper years.

Harvest

3-9 days after flowering pods will be mature (it takes 40 days from flowering to mature seed).

For maximum yields it is important to harvest at least every second day. If pods are missed, they will mature and limit the future flowering and therefore the yield.

We harvest six days a week, using pruners, or a small serrated knife. The stems are quite tough. Some people find their skin is irritated by the spiny leaves and like to wear long sleeves when harvesting. We cut Cow Horn at 5” (13 cm) or bigger. Some years we have attached a piece of card to special pruners for the job, showing the size to cut. Do not make assumptions about toughness without testing with a thumbnail, or snapping off the tip. We’ve also been surprised to find it necessary to show new people the difference between a rounded “empty” pointed flower bud, and an angular firm pod.

Our harvest starts in mid-July and runs until frost, a period of 12 weeks or so. At the end of the season, we find we need to dig out the massive trunks and consign them to a spot on the edge of the woods that we call “The End of the World.”

 

Post-Harvest

Okra does not like to be chilled! Here we need to deal with the American tendency to store almost everything in the fridge. Chilling injury of okra causes dark damp spots on the pods, which lead to pitting and slimy breakdown. Okra can be stored at 45-50°F (14-15°C) in unperforated plastic bags for up to 15 days. This compares favorably with only 2 days without a bag, or 7 days in a perforated bag. The plastic bags keep the humidity high.

 

Pickled garlic scapes, okra and beets.
Photo Bridget Aleshire

Okra is very tasty pickled – if you have high yields, time to do the pickling, and a demand for off-season value-added products, go for it.

Seed Saving

Cow Horn okra plant marked for seed saving.
Photo Raddysh Acorn

Saving seed from okra for your own use is a simple matter if you are only growing one variety. We have saved seed by decorating chosen plants with colored plastic surveying tape, like tinsel on a Christmas tree. Then we don’t pick from those plants for eating. We wait until the pods are big and dry, then harvest them before they split and shed their seeds, and put them in bags or cardboard boxes indoors to dry further and until we have time to deal with them. Mature okra seeds are greenish black. For small quantities, just twist the pods and break them open over a container of some sort. Seeds can be screened out of the mixture and/or winnowed. Empty pods make good weed-free mulch.

Okra is outcrossing but can self-pollinate. Okra varieties need to be isolated from each other by 1/8 mile (200 m) for home use, or ¼-½ mile (400-800 m) or greater for seed for sale. A plant population of 10-20 plants is needed for genetic diversity, and more than 20 plants is better for seed for commercial sale. It takes 30-50 pods to provide one pound of seed (66-110/kg).

Breaking dry okra pods to release the seeds.
Photo Southern Exposure Seed Exchange

 

Fruit for the Month: June

Blueberries.
Photo Marilyn Rayne Squier

This is another post in my new monthly series, about small fruits that can be grown sustainably in a mid-Atlantic climate. I’ll talk about planting, pruning, harvesting and care of the plants, according to the season. I’ll give links to useful publications. I’ll have a focus fruit, and then more about others that need attention during the month. We do grow apples and pears, and some other tree fruit, but I’m not writing about those as I don’t have much recent experience.

Blueberries are the focus fruit for June

June is the month in our climate, to harvest blueberries. Blueberries are a great crop to grow, as they are not troubled by many pests or diseases (apart from birds). While you are harvesting take notes (or photos) of the various varieties you have, and when and how well they are producing, so that you will know which ones to propagate from in the winter, if you want more.

See my article about blueberries in Growing for Market magazine

See ATTRA Blueberries: Organic Production available free online, for a wealth of information from choosing varieties, planting, details on pests and diseases you might encounter. Updated 2022. Also search the ATTRA site for other info on blueberries, such as soil management (blueberries need acid soil), living clover mulches, and honeybees and alternative pollinators.

Harvesting blueberries

Blueberry harvest. Note “berry bucket” hanging around the worker’s neck. Photo Marilyn Rayne Squier

I recommend harvesting two days a week, in the mornings, once the dew has dried, to avoid spreading fungal diseases. Blueberries don’t deteriorate or over-ripen as quickly as softer fruit, so if you can only find time once a week, that will be OK. Or if you are selling blueberries, once a week may work better for your sales. Blueberries don’t crush as easily as strawberries or raspberries, so if you have lots you can put them in buckets or crates. We usually harvest into homemade berry buckets with long rope handles, that we can hang around our necks, freeing up both hands for picking berries. Our berry buckets are made by cutting plastic gallon jugs and adding rope through holes we punch near the top. Full berry buckets get emptied into a bigger bucket.

Only pick the berries that are purple-black all over. Check the back of each each ripe-looking blueberry to make sure it’s ripe all over. The area around the stem is the last to change color. Really ripe blueberries will “tickle” from the bush into your hand

Do not wash fruit before refrigerating, as this leads to rot.

Types of blueberries

We grow Northern Highbush blueberries here in winter-hardiness zone 7a (suitable for zones 3-7) and we like to have a crop we can harvest standing up!  There are also lowbush blueberries, which are popular in cooler climates, such as Maine. Rabbiteye varieties are better to the South, in the region roughly south of Interstate 40 (mostly zones 6-9). Rabbiteyes are taller plants, with smaller berries than highbush types. A new hybrid type, Southern highbush, is adapted to the southern rabbiteye zone and the coastal South (zones 6-10). Look into these if you are in the right area: they have a lower chilling-hours requirement, and flower and fruit earlier than highbush or rabbiteye varieties. As the climate changes, fruit growers are challenged by traditional crops no longer getting enough winter chilling hours to fruit. (Chilling is the number of accumulated hours at temperatures below 45°F/7°C in the dormant season.) Balance this with your changing frost dates, as earlier flowering will not be an advantage if your last frost is going to cancel the fruit. Remember that all blueberries are self-fertile but will produce better crops if you plant several compatible cross-pollinating varieties.

Young Blue Crop northern highbush blueberry.
Photo Kathryn Simmons

At our farm, Duke has been a very reliable early fruiting highbush variety, whereas Spartan has not worked out. We like to have several varieties with different ripening dates, to extend the harvest. Blue Crop, Blue Jay, Elliott and Chandler also do well here. If I was starting over, I’d also try some Southern Highbush varieties.

We have bought good plants from Finch Blueberry Nursery in Bailey, North Carolina, as well as from a more local source in SW Virginia (now retired). If you only want a few plants, buy potted blueberry plants locally. Otherwise, order bareroot plants shipped to you. In Virginia Edible Landscaping offers a wide choice.

When to plant blueberries

If you are planning to plant blueberries, here are some considerations. Generally you will want o buy young bushes and plant them in the dormant season. In warm areas, plant in late fall so the plants get roots established before your early spring thrusts them into opening buds. In cooler zones, plant in early spring, so that winter does not kill them.

New blueberry plant with winter wire mesh protection. Photo Kathryn Simmons

As with all perennials, clear the area of perennial weeds the previous year, and reduce annual weeds, for instance by growing a good cover crop, which will smother emerging annual weeds and also feed the soil. Get a soil test, and follow the recommendations to amend the pH to 4.8-5.5 using sulfur in spring or fall before planting. I like the pelleted sulfur, that looks like lentils, because it is easy to spread, and no dust gets in your lungs. Depending on your soil type, you might need 430-1750 pounds of S per acre, or 1-4 pounds per 100 sq ft. Work in some good compost before planting.

Plan space between the rows that will let you walk, mow or whatever you need to do even once the bushes have reached full size. 8-12ft is recommended. Ours are a bit closer than that. In the row you can either plan for a hedge effect, or leave yourself access space. You can plant blueberries on raised beds or wide ridges. You can move bushes later in life, if you find they are competing too much.

Blueberries six years after planting. Photo Kathryn Simmons

Plan how you will cover the soil. I recommend landscape fabric topped by bark mulch or woodchips. This combination works well to keep perennial weeds at bay (wiregrass!). If you are avoiding plastic, you can use double layers of overlapping cardboard topped by 3” of organic mulch: chips, sawdust, straw or spoiled hay. Blueberries don’t do well with plastic mulch that is impervious to water, as it encourages the roots to grow just under the plastic, where they can easily get overheated and die. Some people like to grow a living mulch, perhaps mowing it to mulch closer around the plants once it dries. A hybrid model has mulch in the rows and a cover crop between the rows.

Blueberries have shallow roots, so you will likely need some irrigation method. I like drip irrigation, but overhead sprinklers work too.

You will, of course, have some annual care to provide. Each spring, expect to provide some source of nitrogen and potassium, as needed.  I’ll cover that another time. Each winter, prune for strong branches and good levels of production, and remove any perennial weeds.

Blueberries showing Tenax fencing and basket balls on posts to support roof netting. Photo Kathryn Simmons

Pests to watch out for include big ones like deer, groundhogs, birds and uninvited humans. We have a triple fence, with wire netting in the ground against burrowing animals, 7’ tall Tenax deer fencing, and seasonally, Avigard flexible bird netting over the top. For our newer blueberry planting we make a temporary hooped structure and cover just with the bird netting, held down to the ground with 6” soil staples. This planting is nearer our buildings than the older one, and is not visited by deer or groundhogs.

Blueberry netting on PVC electrical conduit hoops. Photo Pam Dawling

Smaller pests include blueberry maggots, blueberry stem borers, cranberry fruitworms, cherry fruitworms, Japanese beetles, leafrollers, leafhoppers, and aphids. Our perhaps, like us, you will not be troubled by any of these.

Diseases include mummy berry, Botrytis grey mold, Anthracnose, stem blight, stem canker, rust, phytopthora root rot, Phomopsis twig blight, blueberry stunt and several viruses. A Cornell University blueberry diagnostic tool offers a step-by-step exercise to help figure out what diseases may be affecting your crop.

Propagate blueberries by layering a low branch, as you see here with Chandler variety. Photo Kathryn Simmons

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Other small fruits available in June

Two rows of floricane raspberries with a willow and grapes in the background. Photo Kathryn Simmons

Cherries, red raspberries, strawberries, Juneberries, gooseberries  mulberries. Blackberries, apricots, peaches, plums.

If you live in Virginia or nearby, see this produce calendar

Other fruit care in June

New grape vine in May. Photo Bridget Aleshire

Grapes: Mow, weed, water in drought. If you have young vines, remove side branches from the trunks, and fruitlets. Your goal is to first grow strong plants, then produce grapes after that.

Strawberries: Prepare for new strawberries in early June: Disk or till the area for new strawberries if using bare-root plants, and prepare the beds with compost, driptape, and landscape fabric.

June 16-July 16: If using bare-root transplants, plant new strawberry beds.

Late June/early July (after fruiting): Dismantle two-year-old beds. Renovate carry-over strawberries by mowing or shearing/clipping weed and mulch, but don’t compost them. . Plant new strawberries if using bare-root transplants, perhaps rooted runners in the paths of older beds.

Rainbow and Kathryn spread hay over the new strawberry bed. Photo Luke Stovall

All fruit: Water all fruit crops. Weed, mow aisles as needed. Weed and mulch rhubarb, lop flowers. Record condition and fruiting dates of new grapes, blueberries. Note best varieties.

Which Vegetables are Genetically Modified (GMOs)?

Our first sweet corn of the season. Bodacious. Early July. Not GMO
Photo Pam Dawling

Recently we were given a gift of sweet corn from somewhere warmer than central Virginia. It wasn’t Organic, so I wondered if it was genetically modified. I try to avoid eating GMOs, because I don’t support the practice of inserting bits of other organisms in existing crops. Corn varieties often have Bacillus thuriengensis (Bt) inserted in their DNA with the goal of killing caterpillars that eat corn kernels.

USDA Organic symbol

Anything certified USDA Organic is not allowed to have any GMOs in it, so that’s one way to avoid getting GMOs. Growing your own food is a certain way to avoid GMOs, if you don’t buy GMO varieties or suffer cross-pollination from GMO crops.

Non-GMO Project symbol

The Non-GMO Project is the U.S. organization that provides testing and labeling for absence or presence of GMO in products. The “Non-GMO Project Seal” certifies that the product contains 0.9% or less GMO ingredients.

I’m going to skip ahead to talking about which vegetable crops are available in genetically modified varieties, because there are not many, and I’m not interested in worrying people! Then I’ll go into details.

The Big Three GMO Crops in the US

Edamame soy beans (soy for fresh eating). Not GMO.
Photo Raddysh Acorn

Soy, canola and corn are the three food crops in the US that are most likely to be genetically modified. Starting with corn (maize): 92% of all corn grown in the US is GMO. Of corn grown, only 1% is sweet corn. Of sweet corn grown in 2018, 10% is GMO. When you see a field of corn, it is almost certainly GMO, unless you are looking at an Organic farm.

What is field corn? “Corn (such as dent corn or flint corn) with starchy kernels that are used especially as livestock feed or processed into food products (such as cornmeal, corn oil, and corn syrup) or ethanol,” (Merriam Webster). Of the field corn in the US, 40% goes to make ethanol for vehicle fuels, 40% goes to livestock feed, and 20% goes into processed foods for humans.

In 2000, GM StarLink corn was recalled, when over 300 different food products were found to contain a genetically modified corn that had not been approved for human consumption (only animal feed). It was the first recall of a genetically modified food.

What about wheat? Farmers have shown a distinct preference for not growing GMO wheat. This is because much of the wheat grown in the US is for export, and people in many other countries refuse to eat GMOs.

Which Other Vegetables Might be GM?

Here is a 2013 article published in the Journal of Food Science and Technology. “Genetically modified foods: safety, risks and public concerns—a review” by A. S. Bawa and K. R. Anilakumar

There are only a few vegetables that have any GMO varieties. Some have been tried and failed. All vegetable seed is non-GMO unless labeled, and when purchasing GMO seed, you have to sign waivers. When searching on line, try various labels: genetically modified, GM, genetically engineered, GE, transgenic.

Gentry yellow squash in our hoophouse in late May. Not GMO
Photo Pam Dawling

Summer Squash and Zucchini

To avoid zucchini yellow mosaic virus and watermelon mottle virus in summer squash and zucchini, GM varieties were created, starting in 1995. When I researched GM squash varieties in July 2017 for an article I wrote, I found mention of ten summer squash and zucchini, but now there seem to be fewer. On the Bayer/Seminis website for their squash varieties, in 2017, these all helpfully had a “B” icon (Biotech). The names sound like B-movies: Conqueror III, Destiny III, Liberator III, Patriot II, Prelude II, XPT1832 III yellow squash and Judgement III, Justice III, SV0474YG, SV6009YG zucchini. The website has been updated, as have the variety offerings, and they are less prominently labeled. ZW-20 virus-resistant yellow crookneck squash is a current transgenic line.

In 2005, about 13% of the zucchini grown in the USA was genetically modified to resist three viruses; the zucchini is also grown in Canada (Johnson 2008).

Mexican researchers in 2004 wrote a paper Assessing the risk of releasing transgenic Cucurbita spp. in Mexico. Localities with native wild relatives of transgenic squash were at risk of the greatest trouble from cross pollination. The genetic legacy of ancient squash lineages was at risk. Gene flow between crops and their wild relatives was widely documented. The authors urged much caution about where and when GMO squash should be permitted.

GM squash also poses a risk that its virus genes or the proteins they produce could interact with other viruses to produce new diseases. And, as with any genetically engineered crop, the squash poses the risk that its new genes might cause it to spread and become difficult to control.

Sugar Beets

The USA extracts 90 % of its sugar “needs” from US-grown sugar beet and sugarcane. Of the domestically grown sugar, half comes from sugar beet, and half from sugarcane. After deregulation in 2005, sugar beet resistant to glyphosate (RoundUp) was extensively adopted in the USA. 95% of sugar beets grown in the US are GM. The sugar produced from GM sugar beets is highly refined and contains no DNA or protein—it is just sucrose. In 2008, the Animal and Plant Health Inspection Service (APHIS), a division of the USDA, performed a court-ordered environmental review of the modified seed and announced that there was no risk to other crops such as beets (beetroot) for fresh eating and pickling, or related crops such as Swiss chard.

Hawaiian Papayas

Since 2010, at least 80% of papayas grown in Hawaii are GM, to get around the devastating problem of papaya ringspot virus.

 

Jubilee tomato in our hoophouse in early June. Not GMO
Photo Pam Dawling

The ‘Flavr Savr’ Tomato

Consumers in the northern regions of the U.S. rely on tomatoes shipped in from the South if they want fresh tomatoes beyond the summer. To survive shipping, tomatoes are picked at the “mature-green” stage. They have already absorbed all the vitamins and nutrients from the plant that they can, but have not started to ripen. To ripen the green tomatoes, they spend 3 to 4 days in rooms where ethylene gas is released, and are then shipped at temperatures not lower than 50 degrees, to preserve what flavor they have.  These tomatoes are probably still a few days away from being ripe.

Calgene, a biotechnology company, developed a tomato with a gene that slows the softening process that happens with ripening. Pectin gives tomatoes their firmness. The pectin in ripening tomatoes becomes naturally degraded by an enzyme and the fruits soften, making them difficult to ship.

The scientists “reversed” the tomato softening gene and reintroduced it into the plants. Reducing that enzyme in tomatoes slows cell wall breakdown and keeps the fruit firmer for longer. In order to tell if their “Flavr Savr” gene was successfully inside the plants, scientists attached a gene that makes plants resistant to the antibiotic kanamycin. By exposing the plants to kanamycin, they could tell which plants had accepted the Flavr Savr gene. Once in a tomato plant, the Flavr Savr gene attaches itself to the gene activating the softening enzyme. When the Flavr Savr gene is there, the “softening” gene cannot give the necessary signals to produce the enzyme that destroys pectin.

Production of the Flavr Savr stopped in 1997. Production costs were too high, and consumers did not find a benefit. See Whatever Happened to the Flavr Savr Genetically-Engineered Tomato

A ladybug on a potato leaf, looking for pests to eat. Ladybug larvae eat eggs such as Colorado Potato Beetle eggs. Not GMO
Photo Kathryn Simmons

NewLeaf (and other GM) Potatoes

 The NewLeaf GM potato was brought to market by Monsanto in the late 1990s. It was developed incorporating Bacillus thuringiensis (Bt) bacteria to kill Colorado potato beetles. The target audience of fast food retailers rejected it and food processors ran into export problems. It was withdrawn from the market in 2001.

In 1998, a safety study (Ewen and Pusztai 1999) of GM potatoes with incorporated snowdrop bulb lectin (GNA) gene (Lectin acts as an insecticide), showed significant changes in the intestines of rats fed GM potatoes. The tested potatoes were not a commercial variety and not intended for human consumption, but the public were alarmed.

In 2010 Amflora was developed by BASF Plant Science for production of pure amylopectin starch for manufacturing waxy potato starch. It was approved for industrial use in the European Union in 2010, but was withdrawn in January 2012 due to rejection by farmers and consumers.

In 2011, BASF requested approval for its Fortuna potato as feed and food. The potato was made resistant to late blight by adding resistant genes that originate in the Mexican wild potato Solanum bulbocastanum. In February 2013, BASF withdrew its application.

In 2014, the USDA approved a GM potato type, Innate, developed by the J. R. Simplot Company that contained 10 genetic modifications that prevent bruising and produce less (carcinogenic) acrylamide when fried. The modification uses RNA interference (deactivating genes already present), rather than introducing genetic material from other plants or animals. Ranger Russet, Russet Burbank, and Atlantic potatoes are examples of varieties using this technology. McDonald’s announced that they have ruled out using Innate.

In 2017 scientists in Bangladesh developed a GM variety of potato resistant to late blight.

Arctic Apples

In February 2015 Arctic Apples became the first GM apple approved for sale in the US. RNA interference is used to reduce the activity of polyphenol oxidase, preventing the fruit from browning.

Mushrooms

In April 2016, a white button mushroom (Agaricus bisporus), genetically modified using the CRISPR technique, received the go-ahead, as the USDA considers it exempt because the editing process did not involve the introduction of foreign DNA, just deletion from a gene coding for an enzyme that causes browning, reducing the level of that enzyme by 30%.

 The Problems with GMOs

When GM varieties are planted on a commercial scale, resistant weeds and pests can evolve. The emergence of resistant insects can negate the effects of a Bt GMO. Also, if herbicide spraying becomes more frequent on herbicide-tolerant GMO varieties, weeds can develop resistance to the herbicide. This can cause an increase in herbicide use or an increase in the amount and types of herbicides used on crop plants. It is not a coincidence that herbicide producers are behind this research.

Further investigation is needed to learn if residues from herbicide- or pest-resistant plants could harm soil organisms. Another uncertainty is whether the pest-resistance of GE crops can cross to related weeds, creating resistant weeds. Possibly insect-resistant plants can cause increased death rates to one specific pest, decreasing competition and allowing previously minor pests to become a major problem. Also, it could cause the pests to move to another plant that had been unthreatened. A study of Bt crops showed that beneficial insects are also exposed to harmful quantities of Bt. It is possible for the effects to reach further up the food chain to affect crops and animals eaten by humans.

It is possible that virus-resistance can lead to new viruses and new diseases emerging. Naturally occurring viruses can recombine with viral fragments, forming new viruses.

The main concerns about adverse effects of GM foods on human health are the transfer of antibiotic resistance, toxicity and abnormal immune responses. A known allergen may transfer from a GM crop into a non-allergenic crop and create a new allergen. Patients allergic to Brazil nuts and not to soybeans showed an allergic response towards GM soybeans.

  A Law on our Side

In January 2022 the National Bioengineered Food Disclosure Standard became mandatory. The new Standard requires food manufacturers, importers, and other entities that label foods for retail sale to disclose information about BE food and BE food ingredients. This rule is intended to provide a uniform national standard for providing information to consumers about the BE status of foods. The Final Rule was published in December 2018

 

Bioengineered Food symbol

The BE Food Disclosure must be placed on either the main information panel on the label, or an alternate panel “likely to be seen by a consumer under ordinary shopping conditions.” For bulk foods, retailers are responsible for displaying the BE food disclosure on or near the bulk item. Now you know what to look for!

More on Insectary Flowers; Vegetable Crop Resources, Especially Weeds

 

Borage flowers attract many beneficial insects. Spot the honeybee! Photo Raddysh Acorn

More on Insectary Flowers (to attract beneficial insects)

A reader responded to my post Growing flowers to attract aphid predators in early spring

“Isn’t too cold for the predators to be around, Pam? unless they hibernated in the greenhouse. but even so, it’s still cold in there at night. We have some aphids too in the tatsoi and some of the lettuce, so thank you for all the tips, and the life cycle. I had not quite realized that the cycle was so short. I grow borage in the hoophouse but in the ground – the plants get large and gorgeous with clouds of blue flowers in March and April – much bigger and healthier than anything I try to grow outside. The honeybees absolutely love it and they attract are a lot of other insects too.”

Yes, it has been still too cold for predatory insects to be around, until this week, when ladybugs greet us around every corner. Our idea with the flowering plants was that by starting the plants in the fall, we’d have actual flowers earlier than if we started in “spring”, and that perhaps the extra stresses would even cause the plants to flower earlier. Apart from the borage, none of the others have flowered yet (Feb 23). We likely need to fine tune our sowing dates. We sowed at the very beginning of September and the very end of October. That two-month gap probably has better sowing dates! We noticed that some of our plants were not very cold-hardy. Some died and some had to be pruned of dead bits. Since then, we started more flowers in our greenhouse on February 1. Another thing we’re noticing since early February is that the plants in pots dry out very fast. It’s probably better to get the flowers in the ground in the hoophouse and greenhouse as soon as they are big enough, as suggested by the results of my reader quoted above, with borage.We had thought that having them in pots would enable us to move them into trouble spots.

Vegetable Crop Resources, Especially Weeds

Spiny amaranth – a weed to exterminate by careful pulling.
Photo Pam Dawling

A newly released handbook from Sustainable Agriculture Research and Education (SARE), Manage Weeds On Your Farm: A Guide to Ecological Strategies by Charles L. Mohler, John R. Teasdale and Antonio DiTommaso, is set to help us all. I haven’t read it yet (although I am looking forward to that!), so this is not a review, But these are three big names in weed science, and SARE is well-known for providing solid information on sustainable farming.

Silver Queen sweet corn with a wilting pulled amaranth plant in the center
Photo Kathryn Simmons

I had the great good fortune to attend a workshop by Chuck Mohler years ago, and got some realizations that forever changed my approach to weeds. Top of the list is that some weeds, such as pigweed (amaranth species), don’t distribute any seeds until they have grown very big. Until that point they are not threatening next year’s farming efforts. We used to get huge pigweed plants in our sweet corn, and fatalistically did nothing once we were in there harvesting, somehow believing it was “too late”. No, it’s not! They hadn’t seeded. We started to make a practice of pulling the huge pigweed every two days while harvesting corn. Often it was necessary to stand on the base of the corn plant to hold it in place, while pulling the weed. Then all we had to do was drop the pigweed between the rows. Sweet corn ripens in hot weather and the weeds soon died, rather than re-rooting. All those big leaves sucked the moisture right out of the plants. Be extra careful if you have spiny amaranth. We have twice eliminated this weed form our gardens, by diligent hand-pulling, only to have it reappear a few years later!

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

Conversely, galinsoga forms seeds very soon after germinating, while still small. This weed is one to strike early and repeatedly. It readily re-roots in damp soil. Our strategy when we are too late to hoe and have to hand-pull them, is to shake off as much soil as possible, then to either twist and break the stem (if there are not many), or “shingle” the weeds, laying them down with the roots of one on top of the leaves of the previously pulled plant, providing a surface of roots all exposed to the air, and none touching the soil. This works quite well. Timely hoeing is much better, of course!

Manage Weeds has chapters on How to Think About Weeds, Cultural Weed Management, Mechanical and Other Physical Weed Management Methods, Profiles of successful managers,  and then the alphabetical rogues gallery of grass weeds and broadleaf weeds.

This book and all the online information from SARE is free of charge. You can buy print copies if that suits you better. Other good resources from SARE, while you’re at their website, include several other books:

Building Soils for Better Crops

Managing Cover Crops Profitably For many of us, this is the “Cover Crops Bible”

Systems Research for Agriculture

Crop Rotation on Organic Farms 

There are also podcasts, bulletins, videos, Topic Rooms and interactive pages to explore.

Winter Vegetable Production Methods

For those who missed the Pasa Sustainable Agriculture conference, here is my slideshow Winter Vegetable Production Methods, From the Field to the Hoophouse

Winter Vegetable Production Methods, From the Field to the Hoophouse Dawling 60 mins 2022 2.11 9am

Some Highlights of the PASA Conference

I enjoyed attending the in-person conference of Pasa Sustainable Agriculture. This is the first conference I’ve been to in person in two whole years. PASA did a lot to ensure the conference was as Covid-safe as possible. They limited the number of attendees (there were still plenty to ensure lots of chances to exchange information). Everyone had to test on their day of travel to the conference, and speakers had to test every day of speaking. For me that was all three days. Everyone was masked, nearly all with KN95 “real” masks. The hotel housekeeping staff only came in after we left. (We could have requested the service, but, heck, I can make my own bed!) In the workshop rooms, the chairs were spaced 6 ft apart. The trade show had wide aisles, and meals could be taken out of the dining room to a quiet spot. Just getting to be there was a big highlight for me! I left feeling energized and enthused, and very grateful to the PASA team for preparing such a successful event.

There were four sessions of workshops each day, with one-hour breaks between, allowing time to visit uncrowded trade booths, catch up with old friends, and make new ones. We were well-supplied with snacks and beverages during the breaks. There were socials with more snacks at the end of the day.

I did have trouble with the conference app, but then, my phone is limited in what it can do. Likewise I failed to upload my slideshows to the platform, so I ran them off my flashdrive. My pdf handouts did make it onto the app, so if you wanted one of my handouts, you can find it there and here:

Young Yukina Savoy plants.
Photo Ethan Hirsh
Optimize your Asian Greens Production Dawling PASA handout 2022 2.10 9am
Young spinach seedlings.
Photo Pam Dawling
Winter Vegetable Production Methods From the Field to the Hoophouse Dawling 2022 2.11 9am 6 page handout
Sweet potatoes in storage. An ideal crop for winter meals, as they store at room temperature for a long time, maybe seven or eight months.
Photo Pam Dawling
Growing Sweet Potatoes from Start to Finish Dawling 4 pg handout 2022 2.12 11am.docx

Each of the ten workshop sessions had a choice of eight or nine workshops. I had thought I might hunker down in my hotel room when I wasn’t speaking, to minimize my chance of catching Covid, but as permaculture author Darrell Frey said “This feels safer than going to the grocery store!”

I enjoyed several workshops presented by others, including:

On-Farm Experience with Organic No-Till

Sam Malriat from Rodale

No-Till sequesters carbon in the soil, but simply never tilling does not improve the soil. Chemical no-till uses lots of herbicide. Don’t be obsessive about no-till. Shallow tillage can be a responsible choice, as incorporation of organic matter is valuable. Adding cover crops, compost or manure, grazing, and a good crop rotation, can increase the OM, and thus increase the soil water capacity enormously.

Crimson clover cover crop
Photo by Bridget Aleshire

To overcome the challenges of no-till, you need a very good cover crop stand that will provide a thick mulch when terminated; a competitive cash crop; a way to plant into the residue, and a back-up plan in case one of the requirements doesn’t pan out.

Sowing corn into rolled and crimped hairy vetch does not work well, because corn is a heavy feeder and not very competitive. Better is to undersow the corn at V5 or V6 (stages of vegetative growth) with white clover or crimson clover in September. It’s important to get good seed to soil contact. The clover grows when the corn dies. This is in Rodale Country in PA. If the clover can be left growing until the second year, cabbage can be transplanted into it. His slides showed the success of this system after an unpromising start.

Pumpkins can be direct seeded in crimped and rolled (or mowed) winter rye. There is a lot of difference in thickness of the mulch between rye sown in August and October.

Organic Solutions: Pest Management

Drew Smith and Emily Gantz from Rodale

There was a big drop in pesticide use in the mid 1990’s as GMO crops came in. But then a big uptick as resistance to the GMO crops developed. Currently, almost all non-Organic seeds contain neo-nicotinoids, even though they provide no economic benefits.

Crop rotation is the single most important thing you can do to manage pests. Drew showed us the IPM triangle, and we worked our way up. To succeed in preventing pest infestations, planning of all aspects of growing the crop is vital. As is regular scouting of each crop. Cultural controls include the physical aspects of the planting. Other physical controls include mechanical aspects of growing the crop. Biological controls include encourage beneficials, releasing biological agents. Greater biodiversity provides greater stability. See Cornell Entomology https://biocontrol.entomolgy.cornell.edu/index.php

Native Pollinators: Identification, Habitat Needs and Resources

Sarah Koenig and Ryan Stauffer from the Audubon Society

A bee pollinating squash.
Photo Pam Dawling

There are 4000 species of bees in the US (20,000 globally). 70% of food crop species rely on honeybee pollination to some extent. Native bees mostly nest in the ground. Don’t kill them by compaction (or weedkillers!). Use native flowers to attract native pollinators.

Using Tarps to Reduce Tillage on Small Vegetable Farms

Ryan Maher, Cornell Small Farms & Bob Tuori, Nook and Cranny Farm

More growers are trying tarping for weed control, killing cover crops, maintaining a good soil temperature, avoiding crusting and compaction, keeping beds dry enough for planting and reducing dependence on single-use plastics. Challenges include the heavy weight, the aggravation of using sand bags, especially in windy places, ponding of rainwater runoff, and the frustration of providing perfect vole habitat.

After 28 days in summer, you gain 200 GDDs. Plant-available soil N increases by 2 or 3 times from the plant residues. How soon does it dissipate after removing the tarp? Tarping for 3 weeks after shallow tilling kills the living weeds, improves crop establishment and reduces weed emergence by up to 83%. Think of tarps as a tillage tool! Do plan for weed management after removing the tarp. Pigweed and amaranth can become worse!

We haven’t tried tarps yet. Early September photo of hay mulched June-planted potatoes.
Photo Kathryn Simmons

Bob Tuori spoke about a SARE trial of tarping in the Northeast. He compared potatoes grown with and without prior tarping, both patches with and without hay mulch after planting. The tarped area needed sandbags every 10-15 ft. The tarp was removed June 4, weeds were counted June 24, then the patches were mulched. (I hope I got that right). I did not write down all the results, but the only-mulch area grew 17.4 lbs per hour of work, and the tarp-only area grew 13 lbs per hour of work. See the SARE report for the details.

Harvesting Techniques for Small- to Mid-Scale Vegetable Farms

Julie Henninger of Good Keeper Farm and Matthew Lowe

We saw good tool and equipment storage, and learned the benefits of growing head lettuce on landscape fabric (no rotten bottom leaves, no weeds). Muir is their favorite lettuce for spring, summer and fall. At $3/head, a 95ft row planted at 9” spacing earns them $1300, if they have a 15% loss.

Beautiful baby lettuce mix in our hoophouse.
Photo Wren Vile

We learned the importance of sharp knives or scissors for cutting baby greens with minimal cell damage and browning. Theirs sells at $12/pound. They grow Salanova, which brings in $1140/bed at each cutting. If they cut whole heads, these bring in $1476 per bed.

For loose carrots, they sow rows in pairs 2” apart, with 6 rows on a 30” bed, using a stale seed bed and flaming. They sell 1000 lbs per week. Julie Henninger emphasized not wasting time by setting the carrots down in piles. Minimize the number of times each crop is touched. They have modified a cement mixer to wash 25-45 lbs at a time.

Training and communication are also very important. New workers must master the task first, before chatting. Minimize distractions. Send crews out with a strong role model each, to keep the crew working at a sustainable pace. If working with a crew with diverse abilities (eg children), provide a clear short task with a beginning and an end, to give a good sense of achievement.

I also attended the Plenary, Why Is Farming So Hard & What Can We Do About It?  on Friday with Brennan Washington, Sarah Mock and Dr Jessica Gordon Nembhard, who were livestreamed and recorded.

I participated in the book swap, setting out some spare handouts I had in exchange for a couple of magazines. I enjoyed the Farm Innovations poster display of tools and techniques to improve production or save resources (or both). I liked that previous years’ posters were available as pages in several ring binders.

In the Trade Show there were 60-odd vendors. I checked in with Nifty Hoops, a company who will deliver a hoophouse and put it up for you in one day, or help you put it up, teaching as you build. We put ours up ourselves, in 2003, and we were inexperienced and slow, and had to work on it in the (hot) afternoons, after spending the mornings farming. At events when I talk about hoophouse growing, I’ve sometimes been asked if there are companies who will erect hoophouses (high tunnels), so it’s good to be able to pass on this contact. Nifty Hoops also sell interesting components such as DC-powered inflation blowers. (734) 845-0079.  They have videos on their Facebook page

I picked up some publications from ATTRA, who have supplied me with great vegetable growing info since before the internet. (We used to call them up and ask for publications to be sent in the mail).

The Mini-Treffler manual harrow

I also was fascinated by the Mini-Treffler, from OrganicMachinery.net, a manual rolling tine harrow for crops in beds.

  • The TINY Treffler is a hand drawn harrow with the working width of 80cm (2 ft 7 in), 100 (3 ft 4 in) and 130cm (4 ft 3 in)
  • Shares the same principle with the big Treffler harrows: in the row harrowing, adjustable tension and the patented tine suspension
  • Each tine follows the contour of the field and the downward pressure remains constant
  • The TINY is effective throughout the growing season in greenhouses or for small enterprises in vegetable production or seed propagation
  • Wheels extendable from one or both sides to straddle a bed

I gathered literature for our garden crew as well as our dairy, orchard and poultry people, and an assortment of free pens, notebooks, stickers.

PASA also had a virtual conference, spread out over a couple of weeks in January. I’m sure there was great information there too, but our rural internet is not up to the task of virtual conferencing, so I’m in the dark. Pasa intends to keep a virtual conference next year as part of the mix – it works better for farmers who cannot easily leave the farm, it reduces the carbon footprint of travel, and saves on travel and hotel or BnB costs. Maybe next year I’ll have better internet. Maybe Covid will have receded. This year’s conference was great! I look forward to next year’s!

 

Growing flowers to attract aphid predators in early spring

Borage flowering in our hoophouse in January, among the lettuces. Photo Pam Dawling

Last July, when sheltering indoors from the heat, planning next winter and spring’s hoophouse crops, I researched and wrote up Controlling Aphids in Early Spring

I also have a post (another July information-gathering project!) about Insectary Flowers to Attract Beneficial Insects outdoors and in, at various times of year. At the end of April we sow several plug flats of different flowers to plant out in Insectary Circles at the ends of our outdoor raised beds. We hope to find a similar approach that will work earlier in the year for hoophouse and greenhouse aphids.

Ladybugs of Maine
Poster from the Lost Ladybug Project

Aphid predatory insects such as ladybugs, lacewings, aphid  parasites, damsel bugs, braconid wasps, rove beetles, syrphid flies, and spined soldier beetles are attracted to plants with small flat open flowers, like alyssum, dill, yarrow, buckwheat, sunflowers, and cosmos. This is a rather loose and general statement. On a big scale this is known as Farmscaping, and you can read about it in a publication from ATTRA; Farmscaping to Enhance Biological Control . You can use this publication to make a specific plan to tackle particular pests. Ladybugs are a good general help because they eat the eggs of many different pest species. Organic Integrated Pest Management from ATTRA gives wider information about managing pests organically.

 

Ladybugs of South Dakota
Lost Ladybug Project

eOrganic has many articles on Insect Management in Organic Farming Systems, that explain ways to tackle pest problems with ecologically-based practices, starting with actions chosen to reduce the chances of the pest ever getting a grip on your crops.

Aphids can get out of control in early spring in our greenhouse and hoophouse, 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 are implementing our plan that we made in the summer.

Insectary flowers against aphids

Meanwhile in January we got bad aphids on the lettuce and, of our flowers to attract beneficials, borage was the only one flowering. It was not enough. We did three sprays of soapy water at 5 day intervals to kill the aphids.

Pepper plant with aphids. Photo Pam Dawling

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.

This week, I want to give a progress report on the flowers we are growing. The chart gives details of the ones we chose, where we found the seed, and which months we decided to plant them in.

September-sown Borage flowering in our hoophouse in January. Photo Pam Dawling

The first planting, in September, was of borage and shungiku (Chrysanthemum greens) only. We hoped these would give us early flowers to start the program. Those plants became big enough to transplant in the ground and in 8” (20 cm) pots. We thought having some in large pots would enable us to move them to the trouble spots.

September-sown shungiku (chrysanthemum greens) in January.
Photo Pam Dawling

What I have noticed is that plants in pots dry out very quickly in both the hoophouse and greenhouse! The shungiku have looked close to flowering several times, and the accidentally dry conditions should have helped them to panic and bloom, but they haven’t. The borage flowered with pompom-like clusters, much more compact than spring outdoor borage does.

October-sown Meadowfoam plants in our hoophouse in January. Photo Pam Dawling

The second planting, in late October, consisted of Meadowfoam, Tidy Tips, Phacelia and Yarrow. Those plants are still small, as I write this at the beginning of February.

October-sown Phacelia in January. Photo Pam Dawling

They have been potted up from cells to 4” (10 cm) pots, and some are ready for bigger pots. No flowers, no help against January lettuce aphids.

October-sown Tidy Tips(and more phacelia) in our hoophouse in January.
Photo Pam Dawling

The third sowing has just happened, on February 1, and includes borage, shungiku, Meadowfoam, Phacelia, Tidy Tips and yarrow. I forgot to sow alyssum, so that will be a little later.

Slow-growing October-sown yarrow plants in January, using space in the path between lettuce beds. Photo Pam Dawling

The September-sown borage and shungiku both had some troubles with cold temperatures during January. We had a mild December, then a January with three non-consecutive nights at 10F (-12C). In our double-poly hoophouse, we roll out rowcover at night if it threatens to be 8F (-13C) or lower outdoors. That was about 6 times so far, but 10F (-12C) has been our coldest. Some of each of the borage and shungiku got cold-damaged, and some got rowcover-damaged (hasty pulling!)

So far, no beneficials have been seen on the borage flowers, and no aphids have been killed as a result. We’re still hopeful, especially about reducing aphid numbers on the peppers. More progress reports to come!

Flowers Against Aphids! Photo Pam Dawling

 

 

Preparing for Spring Transplants

Seed flats in the greenhouse in early spring. See the large lettuces growing in the beds, between flats of seedlings balanced on the bed walls.
Photo Kathryn Simmons

Preparing for Spring Transplants

We have winter to enjoy/experience/endure before we start spring seedlings, but there are some steps you can take to make spring start-up easier and more successful. Of course, there is the usual list of tidying your workspace, preparing to order seeds and repairing tools.

Replacement tool handles

House Handle Company   Telephone: (800) 260-6455 has a wide selection of good quality wood handles online. They specialize in hickory, white oak and ash. Be careful making your selection, and get the handle that’s just right for the tool you are repairing. You can see a lot of their handles in our photos. During the winter we usually have a “Santa’s workshop” day when we repair tools.

There are YouTube videos showing how to make sturdy repairs. Just be sure to shape the handle for a good fit before drilling any holes for rivets. And learn how to make rivets from large nails if none are supplied with your replacement handle. Sharp edges on poking-out badly finished rivets, or nuts and bolts can cause injuries. Sweat we might need. Blood and tears we can do without.

Screening a large pile of compost for the greenhouse beds. Photo Wren Vile

Seed Compost

Today I’m thinking about seed and potting compost.

We use 100% home-made compost for sowing seeds, and for potting-up transplants. We don’t mix in any other ingredients. Our seed compost is our regular good-quality compost, screened to remove large particles, and matured over the winter into a very mellow combination of nutrients and micro-organisms. We make great compost and it grows big strong plants.

We screen a big pile of compost in September, and fill the cinder-block beds in our solar-heated greenhouse. See this post: Screening compost to make our own seed compost for spring. If you are making your own screens, you can use hardware cloth (rat-wire), or do as reader Jim Poole suggested and try stucco lathing instead. “It is quite a bit sturdier. (But watch out for the cut ends when installing it- it can give you a nasty gash.)”

We need a lot of compost, but the idea works fine on a smaller scale too. Find an indoor place near where you will use the compost in the spring, and some tubs to put the screened compost into. If you want the full tub to be on a bench in spring, put the empty one on the bench and screen into it! If you want to grow lettuces in the compost, put the tubs near a window.

Just storing the compost inside over the winter will mean you are not dealing with frozen stuff when you want to sow. But better yet, see Starting Seedlings and Preparing for spring, sowing seeds, for more about how we grow lettuces in the stored compost over the winter in our greenhouse, then use that compost in spring for seedlings.

Greenhouse beds filled with screened compost.
Photo Wren Vile
Lettuce growing in screened home-made compost in our greenhouse in November.
Photo Wren Vile

We transplant lettuce at 10″ spacing into the beds in mid-September or early October. By harvesting only the outer leaves, we keep those lettuces alive and growing all winter to give us salad from November to February. Because we water the lettuces, the compost organisms stay alive and active. If you don’t grow a crop overwinter, water the compost from time to time to keep it slightly damp.

This system provides us with a large quantity of mellow screened compost for seed flats, indoors and not frozen. The micro-organisms have had plenty of time to colonize the compost, so it is full of life. In spring, as we need space in the greenhouse, we pull the lettuce. We can then scoop out the compost to fill the flats for seedlings.

Aphids

The only issue we sometimes have is aphids in early spring. This winter we are experimenting with some plants we hope will flower in early spring and attract beneficial insects who also eat aphids. I’ll report on this project when we see the results.

Here’s what we currently do to deal with early spring greenhouse aphids:

  1. jet the plants with water to project the aphids into outer space (OK I’m exaggerating),
  2. gather up lady bugs, or
  3. if numbers of aphids are really high, we use a soap spray.

We start our first seedlings in mid-January, although we only sow a few things the first week (cabbage and lettuce for outdoors and tomatoes for our hoophouse), and harvesting just one or two lettuces would provide enough compost for those few flats.

Lettuce transplants in soil blocks. Photo Pam Dawling

Soil blocks

We used to make soil blocks for our more delicate transplants (melons, early cucumbers and squash) because there is no transplant shock when you plant them out. We even used them for lettuces at one time. We developed a very simple recipe, which we seem to have lost, but it was something like 1.5 parts by volume of our home-made compost, 1 part of soaked coconut coir and as much water as needed to make a wet slumpy, but not soupy, mix.

I use coir rather than peat moss, because I believe the extraction rate of peat moss is not sustainable, and as a carbon sink, it’s better to leave it in the ground. Coir is a tropical food by-product. I’m sure it’s better returned to the soil where the coconuts are grown.

The mix is compressed into a special block-maker, which is then scraped across an edge of the container of mix, to create a flat base, and then the block is ejected using the spring-loaded handle into a tray or open flat. We line our flats with a sheet of plastic to reduce drying out. It’s important to dunk the block maker in water between fillings to wash off the old remnants and enable the new blocks to slip out smoothly.

The blocks are surprisingly stable – they can be picked up and moved, like brownies. Or you can move several at once on a kitchen spatula. As the plants grow, the roots get air-pruned. Even if you pack the blocks shoulder to shoulder in the tray, the roots from one block do not grow into the others. There is no root damage at all when the complete block is transplanted. Do make sure you press the surrounding soil down and inwards to make good contact with the block.

Okra seedlings in a Winstrip tray in the greenhouse. Note the vented cell sides.
Photo Kathryn Simmons

Winstrip trays

More recently we have come to love Winstrip trays, very durable plug flats with cubic cells that are vented down the sides, so the plants get air-pruned. The bottoms of the cells have finger-sized holes so you can easily pop a full-grown transplant out of the tray. The Winstrip 50 cell tray has cells almost the size of soil blocks. These flats have all the advantages of soil blocks except price. They are expensive. We got ours used. Winstrips have two additional advantages: they are much quicker to use than soil blocks, and they work with all-compost. We don’t add any coir. One less input to buy. I haven’t calculated how many plugs-worth of coir pay for one Winstrip tray. . .

See this post on using Winstrip trays and transplanting plugs from them

For more about soil blocks, and Winstrip and other plug flats, see my book Sustainable Market Farming