Organic No-Till Cover Crops

 

Rye and hairy vetch cover crop. Photo Kathryn Simmons

Organic no-till cover crops are grown to flowering (or very close), killed without tilling or chemicals, and left to become dead mulch for the next crop. The food crops are planted into the dying residue. We have used no-till cover crops for Roma paste tomatoes, which are transplanted in early May. We don’t need early-ripening for these, making them a good no-till food crop. This method enabled us to have 1 year in 10 as a no-till year.

Four ways to kill cover crops without herbicides or tilling

  1. Winter-killed cover crops for early spring food crops
  2. Mow-killed cover crops.
  3. Crimped and rolled cover crops use special tractor equipment. A crimping roller is more successful than a smooth roller. I have also seen photos of an energetic human-powered method involving a T-post lying on the ground across a bed, with two well-coordinated people, one at each end of the T-post, lifting the post with a loop of rope or twine, setting the post back down a few inches further forward and stepping on it.
  4. Mowed and tarped cover crops, kept covered until the roots of the cover crop are dead. With this method, the cover crop or weeds can be killed at any stage of growth. I’m still learning about this, so I won’t say more this time.
We can no longer rely on our winter cover crop oats getting winter-killed. March photo by Pam Dawling

Organic no-till benefits to the soil

  • Soil is kept covered, reducing erosion.
  • Soil compaction is reduced by having fewer tractor passes. Labor, fuel and machinery costs are also reduced.
  • Soil layers are not inverted, the soil micro-organism habitat is undisturbed, the root channels of the cover crops are undisturbed, and the number of earthworms and microbes increases.
  • Soil structure improves, organic matter increases and the cover crop biomass is conserved, rather than burning up as quickly as it would if incorporated.
  • Soil can absorb and retain more water, making it more resilient in drought. Yields are higher under drought conditions than on tilled soil.
  • Soil retains cooler temperatures into the summer, increasing root growth.
  • No new weed seeds are brought to the surface.
  • Some pathogens and pests may be suppressed.
  • Mulch grows in situ – no need to haul and spread.
  • Legumes in the cover crop mix can provide all the nitrogen the next crop needs. The cost of N from vetch seed is half the cost of N from fertilizers.
  • Legumes are a slow-release fertilizer: 15% of the nitrogen in the vetch is in the roots, in position in the soil for the new transplants. 50% becomes available to the food crop as the soil warms in spring and early summer; 50% remains for the following season.
  • Hairy vetch activates plant genes that increase disease tolerance and plant longevity, giving tomatoes an extra 2 to 3 weeks of production
  • Use of agricultural plastics is reduced.
  • If spring is wet, it may be possible to mow, when you couldn’t till.
  • Crops such as pumpkins are cleaner than those grown on bare soil.
Hairy vetch cover crop.
Photo Southern Exposure Seed Exchange

Suitable cover crops for no-till

  • When choosing winter annual cover crops, consider cold-tolerance, the length of the growing season, and efficacy in fixing nitrogen and producing biomass. Do you want a winter-killed cover crop (oats, sorghum-sudangrass) or a hardy one (winter wheat or winter rye)?
  • Using a mixture of grasses and legumes helps limit the loss of N from the cover crop through leaching or denitrification. Generally, use a grass/legume mix in a 2:1 ratio, although you can use higher amounts of legumes, up to 1:1. Hairy Vetch, Austrian Winter Peas, Crimson Clover are all suitable.
  • There are advantages to including more than one legume in the mix – in unusual weather, one may struggle, while the other does better. 

No-till cover crops for early spring vegetables

  • Frost-tender cover crops can be used before early spring no-till food crops. Some growers say it is best to mow or roll the cover crop at around the first frost date, to provide a more uniform mulch in the spring. Weeds may be a problem and the soil will be colder than bare soil — this may work for cabbage and broccoli.
  • For the very earliest spring crops, forage radish, lab-lab bean or bell beans will die back and leave almost bare soil. While they are growing, they suppress weeds.
  • BUT fast-maturing spring vegetables will not do well with no-till cover crops unless you add N fertilizer, as they need nitrogen more quickly than can be got from no-till cover crops early in the year when the soil is cold.
Winter rye and crimson clover cover crop
Photo by McCune Porter

No-till cover crops before suitable late spring vegetables

  • A 1994 USDA trial of various no-till cover crop mulches for tomatoes found that hairy vetch (without added nitrogen fertilizer, and without any weeding) out-yielded plastic-and-fertilizer plots by about 25%, and out-yielded fertilized bare soil by 100%.
  • Late-spring transplanted crops such as late tomatoes, peppers, eggplant, Halloween pumpkins, or successions of cucumbers and squash can do very well after a winter-hardy legume-grass mix no-till cover crop.
  • I have read that transplanting eggplant into crimson clover (sown in the fall before) will reduce flea beetle outbreaks, but I have yet to try it. Mowing after early bud stage will kill crimson clover.
  • At the Coastal Plain Experiment Station in Tifton, Georgia, they have trialed peanuts planted into crimson clover.
  • If you have machinery or hand tools for seeding into no-till cover crops, direct seeded crops are possible.
Rows of Roma paste tomatoes, some on bioplastic, some no-till. Credit Bridget Aleshire

Our example: Paste tomatoes in a mow-killed no-till cover crop mix

  1. We find a plot that will be available in early September: Our spring broccoli and cabbage finish in early July. We follow them with a round of buckwheat summer cover crop.
  2. Then, on September 7–14, we sow winter rye, Austrian winter peas and hairy vetch. 5 oz HV, 1.5 oz AWP, 2.5 oz Rye per 100 sq ft (5 g HV, 5 g AWP, 8 g rye/m2.)
  3. It is vital to grow a solid stand of cover crops for high biomass. The goal is to have the vetch be about 4″ (10 cm) tall before hard frosts of 22°F (-5.5°C) stop growth.
  4. We do not till in this cover crop in spring, but in early May, we mow it very close to the ground using our hay mower (5/1-5/5), just before our tomato transplanting date. We want the cover crop to stay in long aligned stems, not be chopped up small. For small patches, a scythe is better than a weed-whip, for the same reasons
  5. This kills the cover crops. If mowed too early, they will not die. The vetch should be flowering. Rye should be at the soft dough stage – bite a kernel.
  6. We let the mulch wilt for a day, making it easier to work with, before transplanting. We measure and set out stakes and ropes to mark the rows.
  7. We transplant the tomatoes into the dying mulch with as little disturbance of the cover crop as possible.
  8. The vetch and peas (if plentiful) supply all the nitrogen the tomatoes need. We do not add any compost or other fertilizer. The peas reduce the incidence of Septoria leaf spot in the following tomato crop.
  9. In our humid climate the dead no-till mulch keeps weeds away for 6 -10 weeks, by which time it has mostly biodegraded. In climates that are drier or cooler than ours, the mulch will last longer.
  10. In July we roll hay between the rows, to top up the mulch. We plant the tomato rows 5.5 feet (1.7 m) apart and the plants are staked and woven, so we can snugly fit big round bales of hay down the aisles.
  11. This crop doesn’t finish until the frost, and we have all the posts to remove before we can sow a cover crop, so the winter following the paste tomatoes, we usually grow rye with Austrian winter peas.
The Roma paste tomatoes later in the year.
Photo Kathryn Simmons
Roma tomatoes in an earlier year, with rolled hay mulch. Photo Twin Oaks
Plentiful harvest of Roma paste tomatoes. Photo Twin Oaks COmmunity

Cautions about no-till planting

  • Cold-hardy cover crops need time in spring to grow to optimal size before mowing – they are not suitable for early spring food crops
  • Untilled soil in spring is colder than tilled soil: growth of anything you plant in it will be slower, and harvests delayed. Not good for warmth-loving crops such as watermelons!
  • The rate of nitrogen release from the cover crop will be slower than from an incorporated cover crop
  • Transplanting into untilled soil is harder work than planting into loose tilled soil
  • The timing of sowing, rolling or mowing and planting is critical. The wrong weather can jinx your plans
  • If the cover crop stand is poor, weeds will germinate – have a Plan B. Usually this will involve tilling, adding compost and then finding another mulch
  • There may be some regrowth of the cover crop, if mowing was too high, irregular or poorly timed. If needed, mow between the crop rows a couple of weeks later
  • There may be more fungal diseases and slugs
  • In arid zones, it is necessary to wet the mulch weekly to release the nutrients. Drip irrigation won’t do that
  • Hand-seeding into untilled soil is tricky – winter snow and ice can leave soil quite compacted. Unsuitable for small seeded, closely-spaced vegetables. Pumpkins and squash can be direct seeded in crimped and rolled (or mowed) winter rye.
  • Initial hopes for no-till cover crops – that it would be possible to grow vegetables organically without ever tilling again – were unrealistically high

No-till tractor equipment

  • For mowing cover crops, we use our hay mower/conditioner rather than our (rotary) bush-hog, as it cuts close to the ground and lays the cover crop down without chopping it into small pieces. This helps it last longer, and be easier to transplant into. Flail-mowers are recommended over lower-speed sickle-bar mowers, which can get tangled with long vetch vines
  • Roll-killing leaves a longer-persisting mulch than mowing, although there may be problems with re-growth. Adding a method of crimping the stems increases the effectiveness. Hairy vetch is harder to kill by rolling than crimson clover.
  • Ron Morse designed a No-Till and Reduced Till Planting Aid, consisting of a heavy coulter and shank assembly with a wavy coulter behind the shank to slice the mulch and leave a 2″-3″ (5-7.3 cm) strip of prepared soil, for planting in a separate operation.
  • Transplanters are available that are designed for use with thick organic mulches.
  • Direct seeding of large-seeded crops is possible using equipment to open a narrow slot deep enough for the seeds. No-till seeders are harder to find: an example has a toolbar planter, 15″ (38 cm) fluted disk blades to cut through the vetch mat, 15″ (38 cm) double disk opener, 12″ (30 cm) cast-iron closing disks, plastic seed pressers and extra weights.

More on no-till

At the Pasa 2022 conference I went to the workshop On-Farm Experience with Organic No-Till, by Sam Malriat from Rodale.

Sam pointed out that no-till methods sequester carbon in the soil, but simply never tilling does not improve the soil. He recommended we not be obsessive about no-till, but move towards reducing tillage. Sometimes shallow tillage can be a good choice, adding value by incorporating organic matter. OM and soil water capacity can be increased enormously by using cover crops, compost or manure, grazing, or a good crop rotation.

You need a very solid, heavy cover crop stand, to provide a thick mulch when terminated. There is a lot of difference in thickness of mulch from rye sown in August and in October. You also need a very competitive cash crop; a successful method of planting into the cover crop residue, and a back-up plan in case something goes wrong. For example, sowing corn into rolled and crimped hairy vetch does not work well, because corn is a heavy feeder and is not very competitive. A better idea is to undersow the corn at V5 or V6 (stages of vegetative growth) with white clover or crimson clover in September (in PA). It’s very important to get good seed to soil contact, and enough moisture. The clover grows after the corn dies. If the clover is left growing into the second year, cabbage can be transplanted into it.

Rye termination timing: When to successfully crimp

“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.”

Winter rye headed up. Mow or turn it under very soon! Don’t let it shed seed.
Photo Pam Dawling

Cover Crops for April: before the last frost.

 

Beds of young buckwheat.
Photo Bridget Aleshire

In January I shared some resources to give the Big Picture of Cover Crops, including a compilation of slides for SARE (Sustainable Agriculture Research and Education) and my slideshow Cover Crops for Vegetable Growers.

In February, I described limiting winter annual weeds by sowing oats in spaces without a cover crop and no planned food crop for 6-10 weeks. Six–ten weeks (depending on your climate) is long enough in early spring to get worthwhile growth from oats before prepping for the food crop. Also see February’s post for the Stale Seedbed and Tarping Techniques.

In March I wrote about some options for cover crops you might be sowing then, and alternatives like a fast-growing hardy leafy vegetable or mixed Eat-All Greens, an idea from Carol Deppe, a great idea if you have more than eight weeks before your main vegetable crop goes in the ground. This is where using transplants really helps increase your total food output. While the frost-tender transplants are growing indoors, you could be growing a “catch crop” outdoors in spaces that didn’t get a winter cover crop. I also talked in the March post about incorporating cover crops. Remember that if you incorporate fresh green cover crops into the soil, you will need to wait two or three weeks to sow, to give the cover crop time to break down in the soil before it can be available for your crop. Especially, wait three weeks after turning under winter rye before sowing, as it produces allelopathic compounds that can inhibit the germination and growth of small seeds. Transplants don’t suffer the same problem.

Potatoes, weeds and standing water. Until the soil drains, the potatoes cannot be hilled, and the weeds here are already large. The yield will be reduced by weeds out-competing the potatoes. Potatoes may be flamed at 6″–12″ (15–30 cm) tall, to kill weeds without damaging the potato plants. After that, flaming is not recommended.
Photo Bridget Aleshire

Once we get to April here, it is too late to successfully grow oats (they will quickly head up after making very little growth). But in climates like ours, we can sow winter wheat or winter rye in April – they will not head up, but will “wimp out” when it gets hot. That is, they will stop growing, so you won’t get a lot of biomass, but you will have some live roots in the soil, holding it together, taking care of the soil microfauna, and discouraging weeds form germinating. One April when our spring-planted potatoes got flooded, we transplanted potato plants to the drier end of the patch and sowed winter rye in the lower end, once the floods had subsided. This kept the soil covered, scavenged the compost we had spread for the potatoes, and was easy to deal with in July when we harvested the potatoes. It was also much more hopeful to look at an area of green cover crop than an area of green weeds!

April is too soon for us to rely on frost-tender cover crops, but by mid-April, we can sow a mix of oats and buckwheat. The oats will protect the buckwheat somewhat from the cold. if the season is warmer than average, the buckwheat will survive and smother weeds, provide pollen and nectar for beneficial insects

Here’s a lovely quote from Barbara Pleasant in SW Virginia:

“It’s April and the soil is warming up and drying out. After loosening a clump of fall-sown wheat with a digging fork, you pull up a marvelous mop of fibrous roots and shake out the soil. What crumb! The soil’s structure is nothing short of amazing! These are the moments an organic gardener lives for.”

Root systems of four grass cover crops at early stages of growth (two months in a greenhouse). From left: annual ryegrass, barley, triticale (winter biennials) and sorghum-sudangrass (summer annual). Photos by Joseph Amsili. From SARE

Depending on the stage of the year where you are, you could revisit any of the earlier posts. Here are links for each of the cover crop posts in the past year.

May: Buckwheat and Other Summer Cover Crops

June: Sunn Hemp, Soybeans, Southern Peas, and Partridge Pea, Senna Ligustrina

July: Millets and Sorghum-Sudangrass (Sudex)

August: Oats, Barley and Other Winter-Killed Cover Crops

September: Winter Wheat and Crimson Clover

October: Winter Wheat and Austrian Winter Peas

November: Winter Rye (with Austrian Winter Peas early in November)

December: Planning Winter Cover Crops

January: The Big Picture, Ponder and Plan Your Cover Crop Strategies for the Coming Year

February: Oats if you have a 6–10 Week Gap

March: Sowing Options and Incorporating Cover Crops

Perennial and Native Cover Crops

I attended a workshop at the VABF-SFOP Summit on cover crops led by Cerruti R2 Hooks, Veronica Yurchak, from the Department of Entomology, University of Maryland, and Hanna Kahl of UC Davis. The UMD Eastern Shore IPM Center has lots of useful programs and publications. They focus on the most important pest problems and make science-based information available to everyone who contends with pests. This workshop discussed how cover crops influence weeds, plant diseases and insects. Cover crops can smother weeds, augment weed seed predators (lifeforms that eat weed seeds), create a weed-suppressive soil microbe community, release allelochemicals that are toxic to weed seeds, release nitrogen into the crop germination zone, boosting crop growth, cool the soil and compete with weeds for resources.

Cover crops can decrease crop diseases by increasing the diversity of soil organisms, making soil more disease-suppressive; releasing compounds unfavorable to disease organisms; trigger plant immune responses; increase the number of beneficial organisms and forma physical barrier that reduces splash-back from the oil. A nice example is that sunn hemp interplanted in squash rows can cause aphids carrying virus particles in their mouth parts to drop them in the sunn hemp where they do no harm.

Sunn hemp at Nourishing Acres Farm.
Photo Pam Dawling

Cover crops can repel some insects and nematodes, as well as providing habitat, nutrients and protection from predators for the beneficial insects. This can help augment the population of beneficial insects. Cover crops can also act as trap crops for problem insects by being more attractive to them than the crop plants. Cover crops can also cause microclimate change within the crop, for example by acting as a windbreak.

The speaker gave examples with red clover, a short-lived perennial, sown in the previous fall between cucumber rows that were planted in spring. The population of striped cucumber beetles was lower, while populations of beneficials such as big-eyed bugs, minute pirate bugs and ladybugs were increased.

In November 2023, at the Carolina Farm Stewardship Conference, I went to an engaging workshop called On-Farm Cover Crops Research in the Carolinas by Justin Duncan from NCAT/ATTRA, Jason Lindsay from the Southeastern African American Farmers’ Organic Network, and Steve McAllan. See his YouTube  Cover Crops for Hot & Humid Regions. At the workshop, Justin Duncan explained Push-Pull Trap Cropping, invented in Kenya, combining a companion plant that repels a pest with a trap crop nearby that attracts it, making pest control easier.

Pigeon Pea as cover crop. Photo https://conservationist.wordpress.com/2008/11/03/pigeon-pea-as-cover-crop/

He advocated for pigeon peas (Cajanus Cajan) as a cover crop for warm droughty climates, that will also keep the soil cooler. When mean temperatures rise 1 Celsius degree, soils in warm areas burn up 10% of their OM, and cool areas lose 3%. Loss of water leads to loss of OM, leading to more water loss. Hot humid areas need twice as much OM as cooler ones to maintain fertility. No-till can cut the loss of OM by half compared to conventional tillage. Other cover crops Justin Duncan recommended include Perennial Peanut, good in orchards, Chamaecrista rotundifolia (round-leaved cassia) and Scarlet Runner beans. Cover crops are a way of growing Organic Matter in place.

Patrick Johnson, RVA Permaculture. Photo https://rvapermaculture.com/about-us/

Patrick Johnson, a Virginia permaculturist, also gave a presentation on native cover crops. See his Proposal and Project Overview:  https://projects.sare.org/sare_project/fs22-345/

And read the Feb 2024 SARE report Using a Native Legume as a Cover Crop for Soil and Vegetable Production Benefits in Small Scale Vegetable Production.

No-Till Cover Crops

I have not covered these yet, and don’t have much personal experience, apart from our one-year-in-ten growing of paste tomatoes in a mow-killed rye, hairy vetch and Austrian winter peas dying mulch. I’ll make a separate post for next week about combining cover crops and no-till methods.

Cover Crop Training Videos from SARE

See SARE for a series of ten training videos.

Weeds Next

For my next annual series of blogposts, starting at the beginning of May, I will cover Weeds of the Month.

2023-2024 Vegetable Growing Conference Tips 4

 

Alkindus lettuce from High Mowing Seeds

This is the last of my series on tips I learned at sustainable farming conferences the past winter. The sessions reported on here were at PASA.

Harvesting Techniques for Small and Medium Scale Farms

This was presented by Julie Henninger and Andy Russell of Goodkeeper Farm in Gardners, PA. They run a Full Diet CSA, with 7.5 acres of vegetables including five high tunnels and outdoor vegetables, and turkeys, cows and pigs. Their well-organized workshop covered their Top Crops (head lettuce, baby greens, carrots, bunched greens and roots); Pre-Harvest Prep (check list, harvest pouch, rubber bands, sharp knives, bins, other equipment); Techniques; Post-Harvest Work; Pitfalls to Avoid and Meet the Farmers.

For a harvesting pouch they use a nailbag that clips on the waistband, to carry their knives and rubber bands. For harvesting crops, they recommend the Hoss harvest bag. Both leave both hands free for picking.

Hoss Harvesting Satchel leaves hands free.

Goodkeeper Farm practices flaming or tarping to deal with weeds before they become a threat to their crops. All their lettuce is transplanted using a paperpot transplanter. This Japanese designed implement is imported to the US and is now also being made in the US. They favor the red butterhead Alkindus lettuce. See photo above.

For carrots, they grow 6 rows on a 30” bed, spaced as 3 pairs of rows with 2” between the pair. As they harvest the carrots by hand, they broadcast rye, to get the cover crop established as early as possible, and keep live roots in the ground for the most time. They have made a carrot washer from a cement mixer, reducing the size of the belt to slow the machine down. See Root Washers for Produce Farms.

Root Washers for Produce Farms, from University of Vermont Extension Ag Engineering

Top of their tips for techniques is to ensure each person masters the tasks first, limiting distractions. A strong role model demonstrates the technique and the expected pace. After getting those two aspects as second nature, the learner can start to have conversations and other distractions.

In the Pitfalls to Avoid, they list damaging the crops while harvesting, overloading harvest bins, using the wrong harvest gear, failing to invest in good appropriate equipment, dull cutting tools, and actions such as gathering different size bunches, that require re-bunching – try not to need to touch the crops again after harvesting!

Winter Market Gardening

by Catherine Sylvestre, the farm manager at Ferme de Quatre Temps, in Quebec, and co-author (with Jean-Martin Fortier) of the book Winter Market Gardener. Read my review here.

Cover of The Winter Market Gardener

Catherine gave both an introductory presentation and an advanced session with an excellent handout. At their zone 5b teaching farm, they have 27,000 sq ft of sheltered growing: 4 high tunnels, 3 greenhouses and one multi-bay shelter. They offer a two year program for students wanting to learn sustainable farming. They close for a two week break over the winter holidays, and plan their crops to be ready for harvest either side of that break. They need to sow in June for harvests before the break. They have five Principles of Winter Gardening:

  1. Use simple shelters, plastic-covered tunnels, for best profitability
  2. Add minimal heating. By adding 3 Celsius degrees (5.4 F degrees), they double their yields, and avoid using rowcover. Evening out the temperature between day and night reduces stress on the plants. Nutrients are more active if the soil is warmer.
  3. Increase the cold tolerance of the crops. This increases the sugars in the cells, making them more cold-tolerant from then on. Increase the airflow and expose plants to cold temperatures. They start this hardening off at the first frosts, and find that 7-10 days of chilling is needed to create a lasting result.
  4. Be aware that light is the limiting factor (especially for spinach). Their light in November is only one quarter of what they get in August. They plan to grow many crops to size in September and October. Although Asian greens can make some growth Nov-Feb, many crops will not. The ratio depends on your latitude, and is less extreme where we are in Virginia. Grow crops that are less affected by light shortage. Adding artificial lighting is not financially worthwhile.
  5. Well, my notes don’t include #5! It was something to do with appropriate crops, I think. Crops they can grow under shelters with no additional heating: spinach, baby kale, tatsoi, mustards, corn salad (mâche), claytonia, if T19 rowcovers are added for temperatures below 0°C (32°F). They use two layers of rowcover for temperatures below -5°C (23°F) and three layers below -10°C (14°F). They use minimal heating for chard, pak choy, Chinese cabbage, kale, lettuces, turnips, radishes, arugula, sorrel, celery, cilantro, parsley. You could consider soil-heating with PEX tubing filled with glycol (poisonous), 24″ (60 cm) deep in the soil, below cultivation level. At Quatre Temps they use above ground perforated polyethylene tubing in the pathways (it’s OK to step on it, it’s not high pressure).
Tatsoi at Twin Oaks ready for harvesting of whole plants.
Photo Pam Dawling

In the advanced session, we learned more details of their techniques and systems.

  • They start seeds for their winter crops in large cells (4″, 10 cm) so that they can keep their summer crops in the ground for 1-3 weeks longer. When they transplant these, they are careful about spacing, aiming to increase the light falling on each leaf. They plant the crops twice as close in the row, with double-wide spaces between rows, compared to warmer, more light-filled times of year.
  • They irrigate twice a week for 20 minutes, but I don’t know the flow rate of their driptape. From November to January they do not irrigate at all, as growth is so slow.
  • They fertilize in two doses, a little at planting time and more in February, using a mixture of compost, chicken manure and cotton meal, with the addition of feather mela in February. Bacterial activity increase with soil temperature. “Fertilizing cold soils is mysterious. . .”
  • Diseases in winter are mostly fungal. Use strong transplants, with a Rootshield dip before transplanting. They open the sidewalls every 4 hours to remove excess humidity and pay close attention to airflow. If needed, they use Contans.
  • Aphids survive at 5°F (-15°C). At 50°F (10°C) an adult female can create 20 offspring (per day?). At Quatre Temps, they use a three week winter break with no crops to freeze out their shelters. It gets down to -4°C (25°F). They disinfect in spring, removing all plant material, cleaning the structure itself with water and SaniDate (although it also kills beneficials).
  • For heating, a heat pump is very expensive but very efficient. An electric coil is less expensive. A climate battery (aerothermal energy) costs $20,000 and includes 24” (60 cm) diameter pipes deep in the soil, and a large fan. They use one to pre-heat air for the air-tube heating system. Something most of us can only dream about.
  • After the winter break, they direct sow new crops. To provide food for April, they plan gradual crop successions to bridge the gap between winter and spring. This also evens the workload.

Senposai is our star of Asian greens at Twin Oaks. Here’s a bed of senposai outdoors in spring. it grows really well in the winter hoophouse. Photo Kathryn SimmonsCrops they have been trialing include perennial sorrel, which regrows early (mid-Feb); celery and parsley (both very successful winter crops); Tokyo bekana, senposai and komatsuna (grow well in low light); green onions in fall and spring (don’t do well with light levels they get in winter); chrysanthemums regrow well, even in low light.

Book Review: The Barefoot Farmer, Volumes I and II, by Jeff Poppen

The Barefoot Farmer Volume I, 1993-2000

Book Review

The Barefoot Farmer, Volumes I and II. Jeff Poppen, 2001 and 2021, 233 and 221 pages, 6 x 9 inches approximately, with drawings throughout. $20 each or $35 for two, via https://barefootfarmer.com.

The Barefoot Farmer Volume II, 2000-2011

Jeff Poppen at Long Hungry Creek Farm, TN, is a lively and fascinating farmer and writer. Jeff’s style is folksy, lyrical, reverent, amusing, at times whimsical or iconoclastic, and always attentive to what works, what benefits the land, and how to farm better.  No doubt you will heartily agree on some points, and heartily disagree on others! These two small books are compilations of pieces he wrote weekly for his local paper from 1993-2000 and 2000-2011, revised and updated. Jeff is a flexible Biodynamic farmer, who writes for all growers and farmers who care about good food and the long-term future. Jeff’s farming joy spreads wide, with gatherings at his farm, music, TV shows, community events and mentoring young farmers. In addition to these two books, Jeff has written a digest of Agriculture, the teachings of Rudolf Steiner, the founder of Biodynamics.

The articles have been re-arranged by themes, with part of each book on specific aspects of his farming, particular seasons, individual crops, farming past, present and future. The first book starts with the importance of organic matter, compost, and learning from what is happening under our noses and eyes. By watching what a bug does, we may better understand why it’s there and how it relates to the whole local environment. We may learn to make changes in what we do, rather than focusing on eliminating the cause of the holes in the cabbage leaves. Understanding our soil structure will give us appreciation of how the growing and dying of roots improves soil.

Here is an example of Jeff’s humor, realism and humility: “Although I make many tons of compost during the winter feeding of our cattle, it is just not enough. So I’m admitting to an overabundance of idealism and a lack of poop.” He cleans out other people’s barns.

Cover crops increase the canopy of leaves collecting solar energy, transforming it into more plants and then more animals. Mother Nature sends in weeds to cover bare ground. Thomas Jefferson apparently wrote that an acre of buckwheat is worth ten loads of dung. Jeff observed how a field of buckwheat rescued a sweet corn patch. In a dry spring the corn seed did not emerge, so Jeff over-sowed with buckwheat to put some roots in the ground. The buckwheat sprouted with the dew (no rain or irrigation). When the buckwheat reached flowering (still no rain), Jeff noticed the corn had grown, presumably benefitting from the buckwheat roots moving the dew deeper into the soil.

Jeff’s description of broadcasting cover crop seeds is quite poetic, and starts with “I quiet myself.” Many people who have broadcast seeds will recognize the attentive state and loose limbs that are needed to do the job well.

Jeff Poppen Outstanding In His Field

Jeff’s farm became a Community Supported Agriculture farm in 1997, with 32 members paying a monthly fee to receive a box of seasonal produce and opportunities for community events at the farm.

The first book divides crops by season, starting with potatoes in spring, which Jeff chits (pre-sprouts) as we do. By setting the potatoes in flats indoors for a few weeks, the certainty of plant emergence and therefore the yield can be increased, and if the conditions aren’t right on the hoped-for planting date, planting can be postponed, while the potatoes continue to grow. Jeff tried many varieties of potatoes and found that the ones that did best were Kennebecs and Red Pontiac from the local feed store. Funnily enough, we’ve also come down to planting those two, here in central Virginia!

They grow Ebenezer onion sets, knowing they will not store. In the fall, Jeff replants remaining non-storing onions packed in a trench. These provide early green onion tops next year. Onions from seed are started in a coldframe in late September. He plants the bareroot starts out in mid-March. Walla Walla do well for big onions to eat soon, but Copra do best for storage.

With asparagus, Jeff learned the same lesson I did: do not follow instructions to plant new crowns 12″ deep! They will do better 5″ deep. Really!

A week after planting big seeds (potatoes, squash, beans, corn), before seedlings emerge, Jeff runs over the rows with a spike-tooth harrow (large-scale) or rake (small-scale), dispatching tiny weeds without damaging the seeds below the surface. There are many practices like this that we could gainfully employ to reduce our weeding work. When hoeing, observe your plants, and any problems. Squash any pest bugs as you go. Fill gaps in the row from a seed packet in your pocket.

Jeff grows rye and Austrian winter peas for the cover crop preceding winter squash, then in mid-April mows strips down in each place he wants a row, and adds manure. When the squash vines start to run, Jeff mows down more of the cover crop, now flowering, making a no-till mulch right where it’s needed.

Jeff explains the American system of growing some crops on hills, which has always mystified me, an immigrant. He says the root areas dry out more, mimicking the desert conditions they came from. Another reason is helping to locate a large amount of fertility right where these large plants will need it initially. 6-8 seeds are planted in a circle in the center of the 2′ diameter hill, with hills many feet apart.

Jeff describes a sweet potato planting stick made by his neighbor. A stick with a notch in it and an attached wire is used for both pushing the slip down into the soil, and measuring the distance to the next plant. These newspaper articles still contain original comments such as that Jeff has left his surplus sweet potato slips at the feed store for anyone who wants to take some. Later he’ll offer home-grown kale seed, and invite people to leave their bags of leaves at the feed store for him to collect.

The fall garden needs prompt planting. August 4 leaves them 70 days to frost, and is their last chance to sow beans. Cabbages follow their early beans, using the remains of the moisture and compost left by the beans. To ensure the seeds get enough moisture to germinate, he presses them firmly into the soil. He likes to do this by walking heel-to-toe along the row. Yes, he does farm barefoot. And attends conferences barefoot. He wears shoes for tractor work.

Next is a section on putting food by. This includes moving storage crops into more ideal long-term locations, as well as solar drying, canning, jellies, jams, pickles and soups canned in jars. Seed saving follows, including chickpeas (garbanzos) which their local organic gardening club trialed.

Celery is a valuable plant for attracting beneficials if it flowers. In the summer the center of the celery plant dies; we always cut ours out, enabling the side shoots to grow into big plants themselves. I was interested to see that Jeff does as we used to do, moving some large plants into the greenhouse (hoophouse in our case) to supply stalks all winter. Several berry crops are mentioned and I was amused to read that when Jeff asked an orchardist how to keep birds out of his cherry trees, the orchardist replied “Plant mulberries!”

Jeff has done a lot of work with apples, collecting and trying different kinds, and grafting. At the turn of the 20th century there were 6,000 apple varieties (in the US?). Before the turn of the 21st century, we were down to 2,000. Jeff writes about many of his favorites, Lodi, Yellow Transparent, Early Harvest, Little Strawberry, Golden Sweet, Pink Sweet, Grimes Golden (susceptible to cedar-apple rust), Mollie’s Delicious, Liberty (resistant to many diseases including fireblight), Winesaps, King David, Jonagold, Jonagrimes, Gala, Blushing Golden, Rusty Coat, Fuji, Yates, Arkansas Black – all good. Avoid Ben Davis.

Pruning is an important skill (“When do you prune fruit trees? When the pruning shears are sharp”). Jeff avoids winter pruning, apart from removing damaged wood and shaping the tree, and favors May-early June pruning for fruit bud formation. Winter pruning stimulates vegetative growth rather than the formation of fruit buds. When there is plenty of growth happening, fewer fruit buds grow for next year. Jeff has grafting tips too, including that masking tape works well for top grafting.

Volume II includes advice on pears, which are easier than apples to grow without pesticides, if you choose good varieties. Jeff favors Magness, Warren and Maxine, which are resistant to fireblight. Choose a site on a hill, to spill the frosts away, and late-blooming varieties to avoid losing fruit to late spring frosts.

The first book goes beyond the garden into the fields. Jeff is an advocate of integrating livestock into all vegetable production, to improve self-reliance and food quality. Jeff says the annual dropping of manure from one cow can fertilize 4 acres if carefully used, whereas the cow herself only needs two acres of pasture. Cows provide a valuable service, even if you don’t avail yourself of dairy products or meat. Hindus are vegetarians, but may keep cows. Jeff says that ancient wise people forbade the eating of meat, so that cattle, sheep and goats survived the years of famine, keeping the future of their agriculture safe. Rudolph Steiner said that farming is never sustainable without livestock. He proposed that with the proper number of animals, a healthy farm can produce all its own food, feeds and fertilizers.

Jeff gives a brief explanation of Biodynamics and the role of the field sprays, cow horns filled with manure or ground quartz paste, and buried. He makes it clear that fertilizing with horn manure and horn silica do not replace manuring in the usual way. It is vital to continue good farming practices. The six Biodynamic compost preparations, used in tiny amounts in compost and manure piles are thought to radiate living forces and make the compost or manure more effective. It is not necessary to believe this to try it and see what happens. Jeff is on record as saying that when he first learned about the horn manure, he thought it was a load of hogwash. He also noticed that the farms it was used on were wonderfully fertile. He has been using Biodynamic methods (mostly) ever since.

I believe that there are many ways of being a good farmer, and I respect all good farmers. The keys seem to be attentiveness, fantastic memory or good record-keeping, and modifying what you do based on what happened with what you last did.

Jeff writes about planting by the Stars/Zodiac Signs; the fire, earth, air and water elements; and fruit, root, flower and leaf plant parts that correspond in this system. He tries to work with the moon and the planets, but the weather is the determining factor in what they do each day. His approach is that nature is forgiving, and if you plant on the wrong sign, the seeds can sit in the soil until the right sign comes round again. It is probably unscientific to disregard anything, he says.

The second volume opens with the mission statement of their farm: “Our aim is to grow high quality food and help others do the same, and to educate ourselves on how this is most efficiently accomplished.” There are several sections with topics similar to those in volume I. Jeff believes in using a moldboard plow, slowly, in the fall, to open up new fields for gardens. He likes to let the winter weather convert the exposed soil to a friable state. He recognizes that plowing has gone “out of fashion” and that the soil life suffers and must be replenished. He knows when to stop cultivating soil to avoid destroying the structure. He recognizes when he needs to use a subsoiler or a chisel plow (rebreaker) to break up the hardpan that develops.

In volume II, Jeff often writes about his experiences farming without any irrigation, 2000-2011. Compost, mulch, good humus, can help a lot. Here’s a trick Jeff used in a dry summer to get the fall garden to sprout: right after bushhogging the old beans, summer squash and cucumber beds, he made new furrows and sowed seeds. He walked over the rows, pressing in the seeds. The moisture from the shredded plants and the shade of the old plants (now mulch) was enough to germinate the seeds. Before the use of chemical fertilizers, market gardeners added 50-75 tons of composted manure per acre each year, and had a quarter of the garden space in cover crops at any given time. How much compost to use has been much debated in recent years. Are you really seeing damage if you use more than some people recommend? Or are you seeing better growth, higher yields? Paying good attention is key.

Jeff says “I’ve two answers for most garden questions: Either “add more compost” or “I don’t know.”

In another section, Jeff explodes some garden myths, teasing out the threads of truth they contain. Are heirloom seeds always better than hybrids? For some crops, open-pollinated varieties do well. OP, not necessarily heirloom. For other crops, hybrids do better: broccoli, sweet corn, tomatoes, peppers. Let’s appreciate the skill and hard work of plant breeders who have brought us varieties with better disease-resistance, increased productivity, better weather-resistance, and yes, sometimes better flavor. Let’s see what actually grows best in our particular gardens, for our particular needs.

To qualify for Organic certification, compost must reach 150F, but Jeff prefers not to let his compost get hotter than120F, to preserve more of the original microbes. He also prefers not to turn compost as the certificate requires, but to let it sit undisturbed for a year to encourage fungal growth. Organic certification is not always the measure of good practice. It allows use of some fertilizers that can leach in the soil and harm good microbes. It allows some toxic pest control products extracted from plants. (Maybe not as many nowadays as when written in 2009.) Jeff has moved away from Organic certification, as some other farmers have done, because he considers he can do better than Organic.

Crop rotations optimize the use of soil nutrients, because different crop families use them in different proportions, and return them to the soil in different proportions. Jeff’s approach is to alternate not only crop families, but also plants with varied edible parts: roots, leaves, fruits, to prevent the soil becoming sapped of particular nutrients.

When writing about warm weather crops, Jeff claims that tomatoes like to grow in the same spot every year. This I have strong doubts about. Maybe it works in places with few soilborne diseases and pests. Jeff says they have been lucky (up to 1999).

Some plants do better after particular others. Potatoes don’t do so well after carrots, beets or other crops requiring lots of tillage. Heavy nitrogen feeders such as corn, do well after nitrogen-fixing legumes. Big seeds can be sown in rougher soil than tiny seeds. Jeff rotates crops intuitively, considering the big picture. This is perhaps a method best used by experienced growers with knowledge of the big picture, and not so helpful for beginners, or team-run farms.

Similarly, prioritizing tasks for the day, is easier once you have more than a decade of experience under your belt! If it’s going to rain soon, do the tasks impossible after rain. If it ends up not raining, what will you regret not doing? Don’t just choose the job you most like doing. Keep your mission in mind.

Weeds are best controlled before visible! Prepare the bed, leave it a few days, rake shallowly and plant. A few days after planting, if it is dry enough, rake lightly again, right over the seeded bed. With potatoes, the hoeing between planting and emergence can be deeper, and is very worthwhile. With early-sown carrots, take advantage of the period before the carrots germinate to get rid of millions of fast-germinating weeds. Develop good hoeing posture, keeping your back straight, hinging at the hips, and switching sides back and forth. Don’t get very good at hoeing only to your best side! Jeff paces himself, dividing the length that needs hoeing by the time that seems reasonable. It’s more important to get to the end, doing an 80% perfect job, than to hoe only part of the row, leaving the rest to grow bigger weeds. He reckons on 10 feet per minute. The 80/20 Pareto Principle guides much of his work: “In my life, 20% of the weeds are ignored, 20% of the blueberries are left unpicked, 20% of the grass is unmown, and 20% of my life is a mess. But my cup is 80% full.”

It’s worth pulling up pigweeds that miss the hoeing. Millions of pigweed-loving microbes die and become food for the crops. But if the pigweed continues to grow, pigweed-loving microbes multiply and more pigweed seeds germinate.

The later chapters of volume II are about livestock, pasture and hay, and biodynamics. Not being a biodynamic or livestock farmer myself, I paid less attention to these chapters.

Barefoot Biodynamics by Jeff Poppen April 2024

Jeff has another book coming out in April: Barefoot Biodynamics.

He also has some YouTubes, see https://www.youtube.com/watch?v=msKw7rrfHJo

 

2023-2024 Conference Tips 3 – Climate Change, less usual edible plants

Carrots under shade cloth in summer.
Photo Pam Dawling

2023-2024 Conference Tips Part 3 – Climate Change, Less Usual Edible Plants

I reported earlier on good tips I got from the CFSA Conference and the VABF-SFOP Summit.  Here I’ll continue the theme.

At the VABF-SFOP Summit, I also attended workshops on Meeting the Climate Challenge with Mark Schonbeck, and Eating and Marketing the Whole Plant with Chris Smith. I’ll tell you more about those now, then move on to the Pasa Sustainable Agriculture Conference.

Meeting the Climate Challenge: Sharing Stories, Co-Creating Solutions with Mark Schonbeck

Mark’s slides and handout will be available soon on the VABF website. In our region we are experiencing hotter summer nights, which are hard on plants (and livestock, I’m sure). At 95F (35C) most crops close down completely or slow their growth. For every 1.8F (1C) in warming, 3-10% of the Organic Matter is lost (burned up) and nitrous oxide emissions may increase 18-28%. Daffodils are flowering up to 5 weeks earlier, fruit trees are budding out earlier, risking losing the fruit to freezing nights. In the spring we are getting later cold snaps below 10F (-12C) in March.

We are having a longer frost-free period, with more generations of bugs. Downy mildew of cucurbits is spreading further north than previously.

Our kale beds after heavy rain. Photo Wren Vile

In Virginia we are getting more intense and heavier rains, with more flooding. The erratic nature of the rains means we can experience flash floods, followed by droughts and wildfires. Heavy rainfall leads plants to grow shallower roots, which then die if a sudden drought follows.

Keeping living roots in the soil will increase climate resilience, as will other ways of building healthy soils, such as diversified rotations, and varied agricultural enterprises. Here’s Mark’s list of

6 Organic Principles of Soil Health:

  1. Keep the soil covered
  2. Maintain living roots
  3. Return organic residues to the soil
  4. Minimize soil disturbance
  5. Diversify crops
  6. Integrate livestock.
Teff cover crop.
Photo Wikipedia

Increasing the use of cover crops will help with 1, 2, 3 and 5. Teff can be considered as a summer cover crop in alleys between plastic mulched beds. Mixing with clover gives better soil coverage. I have not yet tried this myself. Oats/barley/peas/mustard sown in March will grow big by June, adding lots of biomass. Oats/radish/legume cover crop mix will winter-kill. Silage tarps and landscape fabrics can help hold the soil in place.

Installing terraces, berms and swales will help with water management. Installing drip irrigation will help manage droughts. Protected growing, in hoophouses or caterpillar tunnels, will help protect from many kinds of extreme weather. There are steps we can take to mitigate climate change, and more information is becoming available.

Eating and Marketing the Whole Plant with Chris Smith

Chris is the author of The Whole Okra, and part of his presentation was about the many uses of okra, beyond cooking the pods. Okra leaf chips are the latest thing he has tried. The leaves are used for soup in Nigeria. The flowers can be eaten or dried for tea. The oil from okra seeds is nutty, citrusy, a bit like olive oil, although the yield is small, at 9-20%. The oil presscake can be ground for defatted flour.

Book Edible Leaves of the Tropics by Franklin Martin, Ruth Ruberte and Laura S Meitzner

Chris showed us a remarkable book Edible Leaves of the Tropics, by Franklin Martin, Ruth Ruberte and Laura S Meitzner. Plants for a Future  has a database of 8000 plants, including edible plants.  The Book of Greens by Jenn Louis and Legume Species as Leafy Vegetables by Robert P Barrett (online) are also valuable resources on edible plants.

DIYseeds.org educational films on seed production

Go to https://www.diyseeds.org  then search for info on growing seeds.

Male squash flowers can sell at $1/flower for an 8-week season. Winter squash yields can increase if some of the early male flowers are removed! Wisteria, redbud and black locust flowers are edible. Kudzu offers many food options (eat it up!) Roots of dandelion, burdock, thistle, sassafras, daylily, dahlia, runner bean and chayote are all edible.

Soil Health, Climate Adaptation and Mitigation Planning, Rachel Schattman, Sara Keleman and Nic Cook

In February 2024, I participated in the Pasa Sustainable Agriculture Conference.  The first session I attended there was Soil Health, Climate Adaptation and Mitigation Planning, with speakers from the University of Maine Climate Science department. They reported that the NE has seen a 15% increase in Growing Degree Days since 1948, and the frost-free growing season in Maine has increased by 14 days since 1895. California has seen a 40-50 day increase in that period. In Maine the temperature changes are greater in winter than in summer. Since 2012, half of the US has shifted to the next warmer winter-hardiness zone. It is helpful to watch indicator species to determine when to plant particular crops. (See my post on Phenology). Warmer temperatures mean that the air holds more water (7% more for each C degree). This means slower storms, more storms heavier rainfall. They also experience droughts, and distinguish between agricultural drought, meteorological drought, and hydrologic drought – be sure which kind your conversations are about.

Young blueberry plant in snow. Photo Bridget Aleshire

Sea level rise is dramatic on the East coast because of past glaciation. The other main impacts they are seeing on agriculture include False Spring (fruit bud kill after a “warm snap”), winter soil erosion and rain ponding, and new pests, diseases and invasive species, warm season heat stress including crop quality deterioration, greater irrigation demands and needs for shade and ventilation (drought can decrease yields 30%), storm intensity including hail and high winds, longer power outages, soil compaction and nutrient runoff, increased rainfall leading to delayed planting and crop losses. These are all possibilities to prepare for. The silver lining is that there may be new crops we can grow, or longer seasons of familiar crops. NRCS, Extension and other resources are available. Climate-Smart Farming and Marketing is a program for farmers from Maine to South Carolina, offering financial support and technical help to farmers implementing climate-smart practices such as cover cropping, agroforestry, reduced tillage and prescribed grazing.

Prescribed grazing is the intentional use of ruminant animals (hoofed herbivores such as cows, sheep, and goats) on the landscape. Unlike conventional grazing, prescribed grazing utilizes a grazing plan that dictates the location and duration of graze periods. This plan is informed by the ecology of the grazing area.” (Community Environmental Council).

Garlic beds next to rowcovered broccoli beds, under a stormy sky.
Photo Wren Vile

We were helped through an 8-stage planning process:

  1. Risk Assessment (prioritizing which aspect of climate change to deal with first). Heavier rains, then high temperatures, wildfire and smoke, plant diseases.
  2. Vulnerability (looking at your system, climate, location, and seasonal time period). Consider both Exposure to the risk and your farm’s Adaptive Capacity.
  3. Option ID. Consider all of small, medium large and total transformation of your farming. Divide your options up into 4 quadrants on axes of cheap-expensive, difficult-easy; low Greenhouse Gas-high GHG, reducing risk-increasing risk; low impact-high impact, quick to install-takes a long time.
  4. Evaluate tradeoffs (financial, ecological, social). Rank your options and select one that meets as many of your priorities as possible.
  5. Try to meet several goals with one solution. Consider seeking advice or funding.
  6. Monitoring and assessment. How will you measure the improvements?
  7. Revising/tweaking. Reflect and assess. Consider success at each stage.
  8. Share what you learned. Don’t expect perfection, or that others will expect that from you.

Next followed a section on funding. Currently there is lots in Inflation Reduction Act coffers for efficiency increases, renewable energy, conservation practices. Try REAP (Rural Energy for America Program), USDA, NRCS, Rural Development Office for your state, SARE funding for experimentation and trials, state agriculture departments, advocacy organizations, regional non-profits, Chesapeake Bay Trust, Farmer Resource Network, county grants, Beginner Farmer grants, grants for historically under-served farmers, Ambrook Accounting software for American farms..

Take a buddy with you to the offices!

Farmer Resource Network

Cover Crops for March: Sowing Options and Incorporating Cover Crops

In March, where we undersowed clovers in the broccoli patch in August, the old broccoli trunks are surrounded by a sea of green clover.
Photo by Kathryn Simmons

In December I wrote about Cover Crop Planning for Next Year, including 5 steps of cover crop planning for all opportunities. I have a slideshow Crop Rotations for Vegetables and Cover Crops, which I find to my surprise that I haven’t posted here since my 2014 version.

Here it is now

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In January I shared some resources to give the Big Picture of Cover Crops, including a compilation of slides for SARE (Sustainable Agriculture Research and Education) and my slideshow Cover Crops for Vegetable Growers.

In February, I described limiting winter annual weeds by sowing oats in spaces without a cover crop and no planned food crop for 6-10 weeks. Six–ten weeks (depending on your climate) is long enough in early spring to get worthwhile growth from oats before prepping for the food crop.

This month I will include some options for cover crops you might sow in March (in central Virginia and similar climates), and then talk about incorporating cover crops, which surely you will be doing this month!

Cover crops to sow in March, and other options

Purple stemmed mizuna. Mizuna and other frilly mustards are fast-growing crops, attractive to the eye and the palate.
Photo Pam Dawling

Depending on the stage of the year where you are, you could revisit any of those posts.

  • In early March the oats plan still works for us.
  • In early spring, the air and the soil are cold, and sowing a fast-growing vegetable crop will not be successful with a gap of less than eight weeks. Crops take too long to grow at this time of year.
  • If you have more than eight weeks you could try those fast-growing vegetables: kale, spinach, Tokyo bekana, radishes, chard, lots of salad crops, senposai, mizuna, tatsoi, land cress. Or try Eat-All Greens, an idea from Carol Deppe. Patches of carefully chosen cooking greens are sown in a small patch. When it reaches 12″ (30 cm) tall, Carol cuts the top 9″ (23 cm) off for cooking, leaving the tough-stemmed lower part, perhaps for a second cut, or to return to the soil.
  • In late March or April in climates like ours, we can sow winter wheat or winter rye – they will not head up, but will “wimp out” when it gets hot. That is, they will stop growing, so you won’t get a lot of biomass, but you will have some live roots in the soil, holding it together and taking care of the soil microfauna, and discouraging weeds form germinating. One year when our spring-planted potatoes got flooded, we transplanted potato plants to the drier end of the patch and sowed winter rye in the lower end, once the floods had subsided. This kept the soil covered, scavenged the compost we had spread for the potatoes, and was easy to deal with in July when we harvested the potatoes. It was also much more hopeful; to look at an area of green cover crop than an area of green weeds!
  • Once we get to March 31 here, it is too late in the year for us to sow oats (they will quickly head up after making very little growth) and too soon to rely on frost-tender cover crops. See the section in February’s post on the Stale Seedbed and Tarping Techniques.

    Tarping beds to kill weeds.
    Photo Cornell Small Farms Unit
  • By mid-April, it is an option to sow a mix of oats and buckwheat. The oats will protect the buckwheat somewhat from the cold. I’ll come back to that idea next month.

Incorporating cover crops, or not

See Barbara Pleasant: How to Take Cover Crops Down. Gardeners working with small tools can start by mowing their live cover crops, grazing poultry on them, or scything them and hauling them aside to use later for mulch. On a very small scale, you can pull your cover crop plants, although I think it is valuable to leave the roots in the soil. On a larger scale, you can graze larger animals, or cut the cover crop down. If the cover crop was winter-killed, the stems will easily disintegrate, so you can skip the cutting down part of these instructions.

If you plan to incorporate the cover crop, choose a mowing method that cuts the plants into small pieces, making them easier and faster to incorporate. On a small scale, this could be a weed whip or a lawn mower; on a larger scale a bush hog. If you plan to use the cover crop for mulch, cut it in a way that leaves the stems as whole as possible. On a small scale this means a sickle or scythe, on a bigger scale, the kind of machinery you might use to cut hay.

Cover crop of rye, vetch and crimson clover in March.
Photo Kathryn Simmons
Rows of Roma paste tomatoes, some on bioplastic, some no-till. Credit Bridget Aleshire

After getting the cover crop down, you could tarp for a minimum of three weeks (allow for more), or you could work the residue into the soil, with a chopping hoe or by digging it in, or using a walk-behind two-wheel tractor such as BCS with a rototiller or a power harrow, or a four-wheel tractor and discs. Cornell has posted a webinar Pairing Tarping with Cover Crops, by Brian Marr.

If you incorporate the cover crop into the soil green, you will also need to wait two or three weeks (or more in early spring) to plant or sow, to give the cover crop time to break down in the soil before it can be available for your crop.

Winter rye produces allelopathic substances that can temporarily inhibit the germination and growth of small seeds. Wait three weeks after turning under before sowing. Transplants don’t suffer the same problem. Oats, wheat, and other cereals also have this tendency, but to a much smaller degree, usually small enough to ignore. Sorghum-Sudan grass hybrid incorporated fresh in the soil hinders the growth of tomatoes, lettuce, and broccoli, but that’s a summer cover crop you won’t need to think about for several months.

I still haven’t got to my Conference notes on cover crop workshops, 2023-2024, but this is enough for one post!

Vegetable Growing Tips, Winter 2023-2024. Part 2 VABF-SFOP Summit

VABF/SFOP Summit conference January 2024

 At the VABF-SFOP Summit in January, I attended the half-day intensive by Jean-Martin Fortier, Market Gardening 2.0. He covered a brief description of what market gardening is, five different crops that are most profitable, and three management tools for profitable farming. He briefly covered his career from 2004 establishing the 1.5 acre vegetable farm La Grelinette with his wife Maud-Hélène Desroches; his 2015 move to run a training farm school, La Ferme des Quatre-Temps,  with 10 2-year trainees per year; his 2023 move to set up a farm-to-table restaurant, Espace Old Mill, very close to home.

Jean-Martin Fortier with his broadfork.

J-M’s five crops for optimal profitability are summer squash, greenhouse tomatoes, garlic, carrots, small eggplants.

For squash, J-M recommends Romanesco, Safari, Gold Mine and Zephyr, harvesting each of their two plantings (in Quebec) for 10-12 weeks. They plant on landscape fabric with melted holes. The squash are netted until flowering. His workshop included all the details. See J-M’s video about using insect netting: https://www.youtube.com/watch?v=QWI30jSQa40. He recommends three types of net: 25 gm net, 47 gm net, and the newer heavy-duty woven net, all from ProtekNet. DuboisAg.com.

Marbonne tomato.
Photo credit Johnny’s Selected Seeds

For greenhouse tomatoes, which are 10% of their sales, they grow Marbonne, Margold, Aurea, Big Dena, Marnero and Beorange, all grafted at 4 weeks of age onto Maxifort or Trust rootstock. This is a highly technical crop, grown with some heating, harvested from early June to October. The spacing is intensive, one row per 30” (75 cm) bed, plants every 13” (33 cm), with the centers pinched out to produce double-header plants. The tomato vines are trained to wires, and the lower-and-lean system is used.

The famous Music garlic.
Photo Southern Exposure Seed Exchange

For garlic, they grow Music hardneck and Siberian softneck, saving their own seed to avoid buying seed lots infested with disease or pests. They plant 2” (5 cm) deep using a dibbler, 3 rows per 30” (75 cm) bed, with plants 5” (14 cm) apart. They combat the leek moths with Tricho-Gard cards containing pupae of the parasitoid Trichogramma wasp. Their garlic sells at $3-$5 per bulb.

Napoli carrots. Credit Johnny’s Selected Seeds

For carrots, they grow Adelaide for earlies, Napoli for fall and winter. They found the tops of Mokum too weak. They rowcover the bed for a week before sowing, to pre-germinate weeds. After removing the rowcover and flaming, they sow the carrots with a Jang seeder. They sow some beets as an indicator, flaming the bed as soon as the beets emerge. For cultivating between the rows of carrots, they use Biodisks on a Terrateck wheelhoe. The bio-disc tool consists of two parabolic discs and two straight discs. It provides precision weeding and hilling on rows on light soils. To harvest, one person loosens the carrots with a broadfork, two people pull bunches.

Fairy Tale Eggplant. Photo johnny’s Selected Seeds

For baby eggplants, they grow small fast-maturing varieties such as Fairy Tale, Orient Express, Orient Charm, Hansel and Nadia, on landscape fabric in an unheated caterpillar tunnel, 1 row per 30” bed, 18” in-row spacing. They transplant at 7-8 weeks, large plants just starting to flower.

Terrateck Biodiscs.
Photo Taerrateck

As well as the Jang seeder and Terrateck bio-disks, they recommend tarping, mini-tunnels, the flextine weeder, and a bubbler (Jacuzzi pump) in the wash tank.

J-M’s management tips include a Monday Morning Game Plan, touring the farm and listing the tasks; making a map and task calendar for every week; sharing the week’s task list with the crew on Monday afternoons, and finishing the day with a preview of the next day’s action list, which helps the crew be ready for an efficient start the next morning. Cap the number of hours of work expected each day. Cap the number of each plant you set out – don’t plant more hoping for the best – this adds costs! Every week, at a consistent time, hold a compulsory Roses, Thorns and Buds session for up to one hour, where each person takes a few uninterrupted minutes to describe their Rose highlight that week (something that made them excited, proud and happy); then the Thorns (something that left them sad, frustrated, angry and why) and finishing with the Buds (something they are looking forward to in the coming week). If a big issue comes up, you could go back to it after the round is completed.

I also attended a workshop on perennial cover crops, that I’ll go into details of in a future cover crops post. It was led by Cerruti R2 Hooks, Veronica Yurchak, from the Department of Entomology, University of Maryland, and Hanna Kahl of UC Davis.

University of Maryland Eastern Shore IPM Center has more information on IPM.

I also attended a workshop on Securing Organic Vegetable Production in Virginia Through Increased Disease Management, by Steve Rideout of Virginia Tech. His recent work has been on Septoria on cilantro and parsley, bacterial spot, bacterial speck and early blight on tomato, anthracnose on peppers, powdery mildew and downy mildew on squash.

Steve described the Disease Management Pyramid, with a base layer of the cropping system chosen. Once this is optimized cultural practices and disease-resistant varieties can be used to further reduce the chance of a disease. Chemical control is a last resort, if all else fails. Heat seed treatments can be used to prevent bacterial spot and bacterial speck. Rutgers has step-by-step instructions for avoiding bacterial canker of tomato including sanitation measures.  To reduce tomato diseases that are soil-borne, support the plants up off the ground, use mulch to prevent splash-back, remove the lower leaves of the plants, and use drip irrigation if possible.

Pepper anthracnose. Photo Bayer.

Pepper anthracnose is hard to control by any means, and some resistant varieties are low-yielding. A 2 or 3-year rotation, using certified seed, reducing humidity in the plant canopy (increasing airflow), removing infected fruit, and using mulch and drip can help.

Cucurbit powdery mildew and downy mildew are very different from each other. Downy mildew strikes cucumbers worst of all the cucurbits. There are two strains. Time your planting to avoid DM, by planting in spring in full sun. There is a Cucurbit DM Forecast Site, which shows the annual spread by county. (Nothing to see in February!). The main symptoms are leaf spots that are yellow turning brown on the upper surface and fuzzy on the underside. Steve recommended DMR401, DMR264, SV4179S, Bricky Brickyard?), Bristol and Common Wealth Seeds South Wind as varieties with best resistance.

Cucumber leaves with downy mildew.
Photo Research Gate.

Cucurbit PM does not trouble cucumbers as much as other cucurbits. It forms a sparse white dusty-looking coating, and does best on dry days with dewy nights of 6 hours or more. Better results are found with a homozygous rather than heterozygous resistant variety. Spraying with water can help, but don’t spray cucurbits with anything if the sir temperature is more than 90F. Sulfur, copper, M-Pede, Serenade and Regalia can help. M-Pede may also reduce pests including deer!

Virginia’s biggest pumpkin disease is Plectosporium blight, which can also affect cucumbers and squash, starting as tiny leaf spots, then scarring the leaf veins on the underside, and the stems. Look for resistant cultivars.

Broccoli head with Alternaria fungus. Photo UCANR

Stepping away from cucurbits and considering brassicas, especially broccoli, next. Alternaria lesions of concentric rings can be hidden in the broccoli crown. Bacterial Rot lesions are seen on the leaf margins, moving in as blocks of affected tissue. It smells bad. Some most-resistant varieties include Emerald Jewel, Green Magic, Marathon, Avenger, Vallejo. Also good are Gypsy, Belstar, Eastern Magic, Burney in hot weather. Expo, Montflor were also recommended. Fungicides are not very effective, but OSO (polyoxin zinc) is the best if you have to.

The Plant Diseases Clinic charges $25 per sample sent to them (this may vary from state to state). See the 2019 Mid-Atlantic Commercial Vegetable Production Recommendations and the 2020 Southeastern Commercial Vegetable Crop Handbook and choose your Organic solutions from those resources.

This post is long enough! I also attended workshops on Meeting the Climate Challenge with Mark Schonbeck, and Eating and Marketing the Whole Plant with Chris Smith. I hop to tell you more about those soon!

Rick and Janice Felker of Mattawoman Creek Farms on the Eastern Shore, VA extended an offer to provide a limited amount pf free assistance to farmers interested in learning more about their crop production and organic certification experiences. Contact Rick and Janice to find out if they still have spare time!

Vegetable Growing Tips from Conferences, Winter 2023-2024. Part 1 CFSA

 

A Spacemaster cucumber plant in our hoophouse on April 23.
Photo Pam Dawling

I love learning new things and getting tips for improving our vegetable production. My events page tells you about recent and upcoming conferences. After I get home from conferences, I usually need to dive back into work, and am in danger of ignoring things I learned. Hence this blogpost. I’ll pass tips on, and extract the gems from my hand-written notes, making it more likely I’ll do something useful with them!

CFSA SAC 2023 banner

In November 2023 I took part in the Carolina Farm Stewardship Conference. I went to an engaging workshop called On-Farm Cover Crops Research in the Carolinas by Justin Duncan from NCAT/ATTRA, Jason Lindsay from the Southeastern African American Farmers’ Organic Network, and Steve McAllan, a last-minute substitute. I’ve got a blogpost brewing about native cover crops in vegetable production, so I’ll save the content for that post. Patrick Johnson also gave a presentation on native cover crops, which I’ll include more about in the promised post.

https://www.youtube.com/c/clem’sorganicgardens

I also participated in a workshop on Advanced Organic Weed Management for Vegetable Growers, given by Clem Swift of Clem’s Organic Gardens, from Pisgah Forest, NC, where they have 8 acres in field production of vegetables. I hadn’t realized the workshop was mostly machinery-focused, but I learned actionable tips anyway! I watched his video on potato planting, cultivation and harvest, which is similar to the way we grow potatoes. I learned a way of covering the edges of plastic mulch by walking backwards with one foot on the plastic to tension it, hoeing soil up onto the plastic. That sounds easier than our method using shovels, but sounds like it does require looser soil than we sometimes have where we use plastic. Clem has a well-organized system of first removing perennial weeds, then cultivating early and often to deal with annual weeds, including using a double-wheeled wheelhoe with a scuffle on either side of the row. Perhaps like one of these:

Double-wheeled double-scuffle wheelhoe. Hoss Tools
Double-wheel double-sweeps wheelhoe. Sweeps available as a conversion kit from Earth Tools.

Johnny’s Selected Seeds has a Wheelhoe Selection Guide in their Tool Library

Next I attended Precise Nutrient Management for Small-Scale Farms by Kyle Montgomery of Advancing Eco Agriculture. Kyle’s goal was to help us answer the question: How could marketable yields be significantly increased with minor changes to a fertility program? Plants have different nutrient requirements at different stages of growth. Sap analysis can show what the plant is taking out of the soil. In each 24 hour period, we want all soluble nitrogen to be converted to stable forms. This was something new for me to think about. I didn’t bring away anything specific to work on.

South Wind slicing cucumber.
Photo Common Wealth Seed Growers

High Tunnel Cucumber Production by Joe Rowland, CFSA’s Organic Initiatives Coordinator, covered preliminary findings from year one of CFSA’s SARE-funded organic high tunnel cucumber project. They trialed 6 varieties of cucumbers grown on 2 different trellis types (drop lines vs Hortanova netting) to compare disease occurrence and severity and marketable yield. Three participating farms replicated the trial to see what works best throughout the region.

Excelsior pickling cucumber. Photo Johnny’s Seeds

Their standout varieties were Itachi, an Asian white slicer (low yield but good disease resistance), and Excelsior pickler (highest yield).

Itachi white Asian slicing cucumber. Johnny’s Seeds

Poniente (a parthenocarpic European slicer) had the most disease of the 6 in the trial; Shintokiwa had the least disease, but was a slow producer, with low yields. The dropline system uses a single leader, more clips, more pruning and twirling than the Hortanova, where two “rows” could be made per bed, training two leaders from each plant in a V. This gave good airflow, slowed down the height-increase compared to single leader plants, and enabled herbs to be intercropped. We grow a succession of five or six plantings of cucumber, mostly outdoors, sprawled on the ground. Only for the early crop does it seem worthwhile to us to grow them in the hoophouse. But I’ve no idea how our yield compares with trained high    tunnel cukes, and perhaps measuring it would lead me to a different plan!

 Poniente cucumber. Territorial Seeds. Note trellis.
Shintokiwa cucumber High Mowing Seeds

Signs of winter, signs of spring

Tokyo bekana in our hoophouse in late December.
Photo Pam Dawling

 My  Winter-Kill Temperatures of Cold-Hardy Vegetables 2021 has not changed much in recent years. But I’ve just got some precise information on Tokyo bekana, the Asian green that grows well in summer as a lettuce substitute; grows very well outdoors in the fall; and grows wonderfully in the winter hoophouse even in low light conditions. In my 2023 list the outdoor killing temperature is listed as 25°F (–4°C).

Ugly, but not dead yet! Tokyo bekana outdoors on January 7, 2024 after several cold nights at 11°F (-11.5°C) at the end of November, and 12°F (-11°C) at the beginning of January.
Photo Pam Dawling

I harvested the last of the outdoor Tokyo bekana in November, except for one plant that was starting to bolt. I left that one to see when it would succumb to cold weather.  It was seriously damaged but not killed at 11°F (-11.5°C) at the end of November, and 12°F (-11°C) at the beginning of January. It was killed by 8°F (-13°C) and 10°F (-12°C) in mid-January.

Now it’s really dead! Tokyo bekana after two January nights at 8F and 10F.
Photo Pam Dawling

My tendency is to move only partway towards my new information each time I get some. This allows my info to gradually center in on the sweet spot, rather than have wild pendulum swings. So for the 2024 list, I’ll cautiously say it dies at 20°F (–7°C). I’ll release my new list for 2024 in March.

I’m updating my Phenology Record with Recommendations for Planting.

Our first crocus . February 1, 2024
Photo Pam Dawling

On February 1st we saw our first crocus bloom (it averages 2/7), our first speedwell, and Hellebore/Lenten roses with big buds (the flowers opened by 2/11). Hellebore often blooms with the daffodils, but our daffodils are only half-height leaves at this point. There are many hybrid hellebores and I’ve no idea which one ours is.

Lenten Rose (Hellebore) buds on February 1,2024.
Photo Pam Dawling

Robin Migration

Robins can be found year-round almost anywhere south of Canada, as residents or short-distance migrants. Birds that breed from Canada to the north slope of Alaska leave in fall for the U.S. Some robins winter as far south as the Southwest, Mexico, and the Gulf Coast.

Robin Range Map from All About Birds.

“Our” robins arrived on February 3rd, partying in an eastern redcedar (juniper) tree, enjoying the berries. According to this All About Birds Robin Range Map, robins are migratory thrushes that can be found here in Virginia year-round. Ours definitely migrate, arriving here anywhere from January 20 (2009) to March 3 (2013). The Virginia Department of Wildlife Resources notes that in mid-late February and early March they fly through headed north.

Eastern redcedar (Juniper) leaves and berries.

The DWR notes: “Robins’ seasonal movements are said to be tied to a 37-degree “isotherm.” An isotherm is a line on a map where the average temperature is the same at various points across the line.  As robins move from southern states into more northern ones, they stop and hunker down when they reach the limits of the isotherm.” They could reach the Arctic in May, if they travel that far!

Also see Journey North’s “Robin Migration Study” website. You can join and report your sightings and hearings of various signs of spring, not only robins.

Speedwell flowering on February 1, 2024.
Photo Pam Dawling

Cover Crops for February: Oats if you have a 6–10 week gap

Oats Cover Crop, Steve Groff farm, Holtwood PA. SARE Soil Health Resources

Cover Crops for February: Oats if you have a 610 week gap

In February, you’ll hopefully have made your crop plans and maps. Perhaps you’ve discovered some beds with no winter cover crop, that you are not using for early spring crops? Those winter annual weeds, chickweed, dead nettle and henbit, will shed lots of seeds if you let them.

If food crops were harvested too late to sow any winter cover crops, in early spring you will be looking at weeds, or “spontaneous vegetation” as I’ve heard them euphemistically called. The first year I gardened in Virginia I had lots of beds in April with purple flowers (henbit, purple dead nettle, some ground ivy) and I couldn’t think what to do – I didn’t need those beds for a few more weeks, so I wasn’t ready to till them. Oh, so wrong! I had squandered an opportunity to improve the soil as well as deal with weed seeds.

Now, when we have the crop plans made, we tag any beds that won’t be used for six weeks or more, till in the weeds and sow oats. In February or March here, with a last frost date of April 30, six weeks is just enough time here to make enough growth to out-compete the weeds and add to the organic matter in the soil.

Examples of crops in our gardens that occupy beds too late for us to sow winter cover crops include late cabbages, the last lettuce, leeks and fall Asian greens. Examples of late spring crops the next year include eggplants, peppers, tomatoes, edamame and chard. In some cases, we might even have no food crop planned until August or the beginning of September.

Six–ten weeks (depending on your climate) is long enough in early spring to get worthwhile growth from oats before prepping for the food crop.

Once we get to March 31 here, it is too late in the year for oats (they will quickly head up after making very little growth) and too soon to rely on frost-tender cover crops. See the section below on Stale Seedbed Technique.

Oats Cover Crops Steve Groff farm, Holtwood PA SARE Soil Health Resources

I wrote about oats as a winter-killed cover crop in August.

Will oats work as an early spring cover crop for you?

Large oat plants will be killed by three nights at 20°F ((–7°C) or by a single plummet to 6°F ((–14°C). Oats seedlings die at 17°F (–8°C). Consider your likely nighttime low temperatures during the period in question, and how likely your seedlings are to die. Oat cover crops of a medium size die around 10°F (–12°C). If they die after growing to adolescent size, no worries – just till them in before planting your next crop.

The minimum soil temperature for germination of oats is 38°F (3°C), and the time required to grow to a worthwhile height in cool weather is 6–10 weeks.

If you are in zone 8 or warmer, oats will not winter-kill, and can be grown in winter too – they may not reliably mow-kill, but are relatively easy to incorporate.

Oat plant and seeds. SARE

Pros and cons of oats as a cover crop

Like most cover crops, oats add biomass and nutrients, increase the biological activity of the soil, smother weeds, reduce soil erosion (their fibrous roots anchor the soil) and absorb and store rainfall. Oats are easy to establish, are fast-growing and particularly good at shading out germinating weed seeds and at salvaging any nutrients (especially nitrogen) left from the previous crop and making them available to the following crop.

In early spring you won’t get as much biomass as from a fall oat cover crop, when you can get. as much as 2000–4000lbs per acre (2240–4480 kg/ha. Certainly not enough to be a no-till cover crop for your next food crop. Oats provide some allelopathic effect (producing biochemicals which inhibit the growth of other plants) although less than winter rye. Like most plants, oats form arbuscular mycorrhizal associations (fungi penetrate the plant’s cell walls and help capture nutrients from the soil) – a mutually beneficial relationship, although probably not a big feature when conditions are cold.

Oats are not as good as some other cover crops at breaking up compacted subsoil, although they do loosen the upper layers of topsoil nicely. (Just where you are going to sow.) Oats do not add nitrogen, and unlike flowering cover crops, they do not attract beneficial insects (assuming they are turned under or mowed before heading up and shedding pollen).

Common Oats. Buy Organic and avoid GMO canola seed inclusions

Buying oats, sowing rates

We used to buy “horse oats” (feed oats) locally and not worry about organically certified seed. But I noticed canola sprouting along with the oats, and I don’t want GMO canola going feral in our gardens! We plan ahead and order extra Organic spring oats in summer when making our big cover crop seed order.

Oats will grow in soils with a pH range of 4.5–7.5, and even do OK in soils without great fertility. They have some tolerance to flooding, but not much to heat or drought (although more than rye).

The sowing rate for drilled oats alone is 80–100lbs/ac (90–123 kg/ha). The broadcast rate is 110–140lbs/ac (123–155kg/ha). On a small scale, this is 4–6 oz/100 sq ft (12–20gm/sq m). Aim to cover the seed to a depth of about 1″ (2.5 cm).

Oats grow to a height of 2–4 feet (0.6–1.2 m) if not killed before then.

Stale seedbed technique and tarping

If you have less than 8 weeks until you need to plant the food crop, you are better off mowing when you can, or weed whipping, to prevent weeds seeding.

Tarping beds to kill weeds.
Photo Cornell Small Farms Unit

You could mow and tarp. I don’t yet have much experience of tarping, but there are good directions in The Lean Micro-Farm and The Market Gardener. There are also online videos. The basic idea is to mow the bed, cover it with a black plastic silage tarp, weight down the edges to get good soil contact and stop the tarp blowing away, and wait till the plant matter has disintegrated, or until you need to use the bed. This will take several weeks in cold weather, (although only a few weeks in summer). If you have a late-finishing fall crop, you could mow and tarp as soon as the crop is finished, and leave the bed tarped until spring. Weeds germinate under the tarp, but then die without light.

For a stale seedbed technique without tarps, you could mow, till several weeks before planting, water (if it doesn’t rain) to germinate weeds, and hoe off those weeds once a week. This can really help reduce the weed seedbank in the soil. It is particularly useful before sowing small seeds of slow-growing crops, such as carrots.

What not to sow in short gaps in early spring

Other quick cover crops, like buckwheat and soybeans, are not at all frost-hardy, so wait until after your last frost date to sow those.

In early spring, the air and the soil are cold, and sowing a fast-growing vegetable crop will not be successful with a gap of less than eight weeks. Crops take too long to grow at this time of year.

 Spring gaps longer than eight weeks

If you have more than eight weeks you could try those fast-growing vegetables: kale, spinach, Tokyo bekana, radishes, chard, lots of salad crops, senposai, mizuna, tatsoi, land cress. Or try Eat-All Greens, an idea from Carol Deppe. Patches of carefully chosen cooking greens are sown in a small patch. When it reaches 12″ (30 cm) tall, Carol cuts the top 9″ (23 cm) off for cooking, leaving the tough-stemmed lower part, perhaps for a second cut, or to return to the soil.

Young spinach seedlings.
Photo Pam Dawling

Undersowing oats in spring

Another way we have used oats in spring is between rows of peas (grown on the flat, not in beds). We sowed the oats the same day as the peas, and lightly tilled the oats in. We mowed the oats as needed during the pea training and harvest period to make access easy. This reduced the number of weeds, and we quite liked the “lawn” underfoot!

Green fallow (Full year cover crops)

If you have a bed with no crop planned for the whole season, you could grow a Green Fallow. You can plant long-term cover crops to replenish the soil. Start with oats or one of the more cold-hardy grasses, and once we get to warm weather, after the frosts, till that in (or mow if it mow-kills) and sow warm weather cover crops.

Reasons not to do no-till food crops in spring

Untilled soil in spring is colder than tilled soil, and growth of anything you plant in it will be slower, and harvests delayed. You could consider broccoli or cabbage, perhaps, but not warmth-loving crops. You may get more slugs and/or more fungal diseases with no-till. The cover crop could try to regrow, or you could get some weeds anyway.

Also, if you are planting by hand, transplanting into untilled soil is harder work than planting into loose tilled soil. Hand-sowing into untilled soil is tricky – winter snow and ice can leave quite compacted soil. If the notion of organic no-till appeals to you, experiment on a small-scale the first year. Reduced tillage is another option. Till out narrow strips in the oats for your plantings of large food crops normally grown on a wide row-spacing.

Using a push seeder for cover crops

EarthWay push seeder.
Photo from EarthWay

You can drill cover crop seeds using a push seeder. See VABF Using Manually-Operated Seeders for Precision Cover Crop Plantings on the Small Farm. Don’t worry if the seed ends up deeper than ideal. It will still germinate.

 

Cover Crop Planning

My book Sustainable Market Farming has a chapter on cover crops and 9 pages of charts about particular options.

The book Managing Cover Crops Profitably (third edition) from the Sustainable Agriculture Research & Education Program (SARE), is the best book I know on the subject. You buy the book or download it as a free PDF from SARE.