Winter-Kill Temperatures of Cold-Hardy Vegetables 2021

Our pond iced over.
Photo Ezra Freeman

Winter-Kill Temperatures of Cold-Hardy Vegetables 2021

I keep records of how well our crops do in the colder season, both outdoors and in our double-layer hoophouse. I note each increasingly cold minimum temperature and when the various crops die of cold, to fine-tune our planning for next year. We are in zone 7a, with an average annual minimum temperature of 0-5°F (-18°C to -15°C).

The winter 2020-2021 was mild, with our lowest temperature being a single late January night at 10°F (-12°C). We had one night at 11°F (-12°C) one at 17°F (-8°C), three at 18°F (-8°C also) and one at 19°F (-7°C). very little snow or ice. Similar to temperatures in the 2019-2020 winter.

The winter of 2018-2019 had lowest temperatures of 6°F (-14°C) in late January 2019, 8°F (-13°C) in December 2018 and a couple of 11°F (-12°C). In early January 2018, we had some extremely cold temperatures of -8°F and -9°F (-22°C and -23°C). Averaging our winter low over those four winters 2017-2021 gives 4.8°F (-15°C), within the zone 7a range.

Georgia Cabbage Collards, good down to 20F (-7C) Photo Southern Exposure Seed Exchange

New Info this winter

I’ve added in some temperatures for collard varieties (Georgia Cabbage collards, McCormack’s Green Glaze, variegated collards) from the Heirloom Collards Project, and also gained some info on spinach (Long Standing Bloomsdale), kales (Rainbow Mix Lacinato) and mustards (Chinese Thick-Stem) from Southern Exposure Seed Exchange. I’ve added in their suggestions on cold-tolerant early spring lettuces, Crawford, Simpson Elite, Susan’s Red Bibb and Swordleaf.

My results from other years still hold up.

Swordleaf lettuce on the right with another lettuce and radishes in spring.
Photo Bridget Aleshire

Using the List

Unless otherwise stated, these are killing temperatures of crops outdoors without any rowcover. All greens do a lot better with protection against cold drying winds. Note that repeated cold temperatures can kill crops that can survive a single dip to a low temperature, and that cold winds, or cold wet weather can destroy plants quicker than simple cold. Crops get more damage when the weather switches suddenly from warm to cold. If the temperature drops 5 or more Fahrenheit degrees (about 3 C degrees) from recent temperatures, there can be cold damage. The weatherman in Raleigh, NC says it needs 3 hours at the critical temperature to do damage. Your own experience with your soils, microclimates and rain levels may lead you to use different temperatures in your crop planning.

Reflect spinach in the open got damaged but not killed at -9F.
Photo Pam Dawling

Outdoor killing temperatures of crops (unprotected unless stated)

35°F (2°C):  Basil.

32°F (0°C):  Bush beans, some cauliflower curds, corn, cowpeas, cucumbers, eggplant, limas, melons, okra, some pak choy, peanuts, peppers, potato vines, squash vines, sweet potato vines, tomatoes.

27°F (-3°C): Many cabbage varieties, Sugarloaf chicory (takes only light frosts).

25°F (-4°C): Some cabbage, chervil, Belgian Witloof chicory roots for chicons, and hearts, Chinese Napa cabbage (Blues), dill (Fernleaf), some fava beans (Windsor), annual fennel, some mustards (Red Giant, Southern Curled) and Asian greens (Maruba Santoh, mizuna, most pak choy, Tokyo Bekana), onion scallions (some are much more hardy), radicchio, rhubarb stems and leaves.

22°F (-6°C): Some arugula (some varieties are hardier), Bright Lights chard, endive (Escarole may be a little more frost-hardy than Frisée), large leaves of lettuce (protected hearts and small plants will survive colder temperatures).

20°F (-7°C): Some beets (Bulls Blood, Chioggia,), broccoli heads (maybe OK to 15°F (-9.5°C)), some Brussels sprouts, some cabbages (the insides may still be good even if the outer leaves are damaged), some cauliflower varieties, celeriac, celtuce (stem lettuce), some collards (Georgia Cabbage Collards, variegated collards), some head lettuce, some mustards/Asian greens (Tendergreen, Tyfon Holland greens), flat leaf parsley, radicchio (both Treviso and Chioggia), radishes (Cherry Belle), most turnips (Noir d’Hiver is the most cold-tolerant variety).

Large oat plants will get serious cold damage. Oats seedlings die at 17°F (-8°C)

Canadian (spring) field peas are hardy to 10-20°F (-12 to -7°C).

Ruby chard, good down to 15°F (-9.5°C). hardier than Bright Lights, but less hardy than green chard varieties.
Photo Kathryn Simmons

15°F (-9.5°C): Some beets (Albina Verduna, Lutz Winterkeeper), beet leaves, some broccoli and cauliflower leaves, some cabbage (Kaitlin, Tribute), covered celery (Ventura), red chard, cilantro, fava beans (Aquadulce Claudia), Red Russian and White Russian kales, kohlrabi, some lettuce, especially medium-sized plants with 4-10 leaves (Marvel of Four Seasons, Olga, Rouge d’hiver, Tango, Winter Density), curly leaf parsley, rutabagas (American Purple Top Yellow, Laurentian), broad leaf sorrel, most covered turnips, winter cress.

12°F (-11°C): Some beets (Cylindra,), some broccoli perhaps, some Brussels sprouts, some cabbage (January King, Savoy types), carrots (Danvers, Oxheart), most collards, some fava beans (mostly cover crop varieties), garlic tops if fairly large, Koji greens, most fall or summer varieties of leeks (Lincoln, King Richard), large tops of potato onions, covered rutabagas, some turnips (Purple Top).

10°F (-12°C): Covered beets, Purple Sprouting broccoli for spring harvest, a few cabbages (Deadon), chard (green chard is hardier than multi-colored types), some collards (Morris Heading can survive at least one night at 10°F), Belle Isle upland cress, some endive (Perfect, President), young Bronze fennel, Blue Ridge kale, probably Komatsuna, some leeks (American Flag (Broad London), Jaune du Poiteau), some covered lettuce (Pirat, Red Salad Bowl, Salad Bowl, Sylvesta, Winter Marvel), Chinese Thick-Stem Mustard may survive down to 6°F (-14°C), covered winter radish (Daikon, China Rose, Shunkyo Semi-Long survive 10°F/-12°C), Senposai leaves (the core of the plant may survive 8°F/-13°C), large leaves of savoyed spinach (more hardy than smooth-leafed varieties), Tatsoi, Yukina Savoy.

Oats cover crop of a medium size die around 10°F (-12°C). Large oat plants will die completely at 6°F (-17°C) or even milder than that.

Garlic shoots poking through the mulch in January. Survive down to 5°F (-15°C), and if killed, will regrow from underground.
Photo Pam Dawling

5°F (-15°C): Garlic tops even if small, some kale (Winterbor, Westland Winter), some leeks (Bulgarian Giant, Laura), some bulb onions, potato onions and other multiplier onions, smaller leaves of savoy spinach and broad leaf sorrel. Many of the Even’ Star Ice Bred greens varieties and the Ice-Bred White Egg turnip are hardy down to 6°F (-14°C), a few unprotected lettuces if small (Winter Marvel, Tango, North Pole, Green Forest).

0°F (-18°C): Chives, some collards (Blue Max, Winner, McCormack’s Green Glaze), corn salad (mâche), garlic, horseradish, Jerusalem artichokes, Even’ Star Ice-Bred Smooth Leaf kale, a few leeks (Alaska, Durabel, Tadorna); some bulb onions, yellow potato onions, some onion scallions, (Evergreen Winter Hardy White, White Lisbon), parsnips (probably even colder), salad burnet, salsify (?), some spinach (Bloomsdale Savoy, Long Standing Bloomsdale,  Olympia). Walla Walla onions sown in late summer are said to be hardy down to -10°F (-23°C), but I don’t trust below 0°F (-18°C)

Crimson clover is hardy down to 0°F (-18°C) or perhaps as cold as -10°F (-23°C)

-5°F (-19°C): Leaves of overwintering varieties of cauliflower, Vates kale survives although some leaves may be too damaged to use. Lacinato Rainbow Mix kale may survive this temperature.

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

-10°F (-23°C) Austrian Winter Field Peas and Crimson clover (used as cover crops).

-15°F (-26°C) Hairy vetch cover crop – some say down to -30°F (-34°C)

-20°F (-29°C) Dutch White clover cover crops – or even -30°F (-34°C)

-30°F to -40°F (-34°C to -40°C): Narrow leaf sorrel, Claytonia and some cabbage are said to be hardy in zone 3. I have no personal experience of this.

-40°F (-40°C) Winter wheat and winter rye (cover crops).

Hoophouse Notes

Winter crops snug in our hoophouse in a December snowstorm.
Photo Pam Dawling

Our double-plastic hoophouse keeps night time temperatures about 8F (4.5C) degrees warmer than outdoors, sometimes 10F (5.5C) degrees warmer. Plus, plants tolerate lower temperatures inside a hoophouse. The soil stays warmer; the plants recover in the warmer daytime conditions (it seems to be the night+day average temperature that counts);

In the hoophouse (8F (4.5C) degrees warmer than outside) plants without extra rowcover can survive 14F (7.7C) degrees colder than they could survive outside; with thick rowcover (1.25oz Typar/Xavan) at least 21F (11.6C) degrees colder than outside.

For example, salad greens in our hoophouse can survive nights with outdoor lows of 14°F          (-10°C). Russian kales, lettuce, mizuna, senposai, spinach, tatsoi, turnips, Yukina Savoy survived a hoophouse temperature of 10.4°F (-12°C) without rowcover, -2.2°F (-19°C) with. Bright Lights chard got frozen leaf stems.

Lettuce Notes

Lettuce varieties for a solar-heated winter greenhouse or hoophouse in zone 7a: (hardiest are in bold) Buckley, Ezrilla, Green Forest, Green Star, Hampton, Hyper Red Rumpled Wave, Marvel of Four Seasons, Merlot, New Red Fire, North Pole, Oscarde, Outredgeous, Pirat, Red Cross, Red Sails, Red Salad Bowl, Red Tinged Winter, Revolution, Rouge d’Hiver, Salad Bowl, Sylvesta, Tango, Winter Marvel, Winter Wonderland.

Cold-tolerant early spring lettuces include Buckley, Crawford, Green Forest, Hampton, Merlot, New Red Fire, Revolution, Simpson Elite, Susan’s Red Bibb and Swordleaf.

Notes on Chicories and Endives

Verona Red radicchio, hardy to about 20°F (-7°C).
Photo Southern Exposure Seed Exchange

Chicories and endives fall into two groups, but they are confusing because the common names sometimes suggest the opposite group than they are botanically. Here’s the best info I have.

Cichorium intybus, commonly called chicories, are mostly heading crops. The group includes radicchio, both Treviso and Chioggia – hardy to about 20°F (-7°C). Belgian Witloof endive (the kind for forcing chicons) is also a chicory. It dies at 25°F (-4°C). Sugarloaf chicory is the least hardy chicory, and dies at 27°F (-3°C).

Cichorium endivia, commonly called endives, are mostly loose-leaf crops, less cold-hardy than intybus types (chicories). This group includes Frisée types and escaroles, which are also known as Batavian endives. They generally survive down to 22°F (-6°C), although Perfect and President endives can survive down to 10°F (-12°C) – can anyone confirm or deny this?

© Pam Dawling 2021


Go to my Events Page for more information on these online events

Mother Earth News Fair Online: Food Independence Course Part Two was released on 3/26/21.

It consists of eight video presentations, most of which come with pdf handouts. My contribution is Growing Asian Greens, and pairs nicely with Guide to Asian Vegetables with Wendy Kiang-Spray, author of The Chinese Kitchen Garden: Growing Techniques and Family Recipes from a Classic Cuisine. Other topics include Dandelion Wine, Homemade Teas, Food Conversations, Passive Solar Greenhouse Design, Productive Growing from Home, and Growing Your Own Spices.

You can subscribe to the All-Access Bundle for $2.99/month (or $35 for a year).

My previous contribution is an 8-part Garden Planning Course

I also did a workshop on Winter Cover Crops for Gardeners as part of the Winter Gardening Course.

All these and many more videos and handouts are available as part of the All-Access Bundle.

 

New and Upcoming Online Events 2020-2021

I’m making this extra mid-week post because I haven’t offered many events this year, and you may have stopped looking on my Events Page!

Click here Make the most of the offseason by getting a step up on planning next year’s garden with this informative and enlightening course from author and Fair speaker Pam Dawling. Workshops include setting your garden goals (how to plan and which crops to grow), mapping, crop rotations, growing transplants, scheduling seedlings, interplanting, contingency plans, and so much more! (Note: If you’ve registered for the All-Access bundle, you now have access to this course!)

Mother Earth News Fair Online

My new contribution to the Mother Earth Fair Online has just arrived – a Garden Planning Course of eight workshops, with handouts, and a resource list.

Workshops include setting your garden goals (how to plan and which crops to grow), mapping, crop rotations, figuring out how much to grow of what, growing transplants, scheduling seedlings, interplanting, contingency plans, and so much more!

Click here to read more and sign up. You can get my Garden Planning course for $20 or the 2021 All-Access Package at $2.99/month or $35/year – the complete collection of online courses (currently 39) and recorded webinars – with more than a dozen new courses in the works! Each online course includes 6-8 video workshops of about 30 minutes each and supporting materials (called “handouts” in the days of physical in-person events).

I also have a workshop on Winter Cover Crops in the Winter Gardening course. There is a link to that course just below my photo on the page I linked to.

This can give you an inspiring way to invest some time this winter. We know lots of new gardens were started in 2020, and maybe you are dreaming of a bigger and/or better garden in 2021. Turn your dreams into plans and get off to a smooth start! 

This big Online Fair also makes a nice gift! (Scroll to the end of the View All Courses second page, for the All-Access Gift icon, 39 courses for $75. It includes a half-price offer on all courses that will be added during 2021.

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Organic Growers School 28th Annual Spring Conference

Online, March 13-21, 2021

The Organic Growers School Spring Conference 2021 is all virtual this time! Attendees will learn how to farm, garden and live organically through 12 tracks and more than 30 workshops.   You won’t have to choose between two or more great workshops that are on at the same time. This year you’ll be able to “attend” every one. In your pajamas if you want.

Kick-off Live Event on March 13, 2021  

  • Three live Keynote Talks
  • Teaser videos for our 12 Themed Tracks
  • Lunchtime Entertainment
  • A live Q&A with our Keynote speakers
  • A video social with other attendees
  • Access to our Exhibit Hall

March 14-19, 2021 – Themed Track Workshops

View 3 pre-recorded hour-long workshops in each of 12 Themed Tracks:

    • Keynote
    • Cherokee Foods
    • Cooking
    • Farming
    • Food Systems
    • Gardening
    • Herbs
    • Livestock
    • Mushrooms
    • Permaculture
    • Soils
    • Sustainable Living

March 20-21, 2021 – Live Track Closing Panel Discussion Sessions

  • Join a live Panel Discussion with each speaker from the Track workshops
  • Interact directly with panelists during the live Q & A portion

In the Gardening Track, Ira Wallace and I will be presenting The Seed Garden. Details to come, as we iron them out.

Garden cart with supplies for watermelon seed collection.
Photo Pam Dawling

I have been slow to join in the world of online events for a few reasons.

One is that in my rural county, we have poor internet connections and slow speed. I cannot reliably participate in a video conference where I’m one of the speakers. The service could just drop my connection at any time. This is a reality of many parts of rural America. We need something like the Rural Electrification Act to bring us into the 21st century. 2017 marked the 80th anniversary of that piece of Roosevelt’s New Deal.

A second reason is that I live as a member of Twin Oaks, an intentional community, where we share values of cooperation, sharing, nonviolence, equality, and ecology. We also share our resources. That includes our bandwidth. We have chosen not to spend a lot of our income on funding fast internet (it could be a deep black hole).

A third reason is that we have chosen to stay home as much as possible, to reduce the risk of Covid-19 infection in our large household. Our group includes people who are more

vulnerable, due to age or health. We chose to self-quarantine, and think of ourselves as in a big bubble. It’s wonderful not to need masks or distancing at home. Anyone who goes off the farm has to be careful about masking and distancing, and about sanitizing on return, even quarantining alone for two weeks if the risk seems high. Going into a city to do video-conferencing is just not something I’m willing to do!

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Articles in Growing for Market

I’ve started a new run of writing articles in Growing for Market, a magazine. Upcoming is an article about collards. In recent months I’ve written about both wet and dry seed processing, planning garlic planting, and methods of growing sweet potato slips.

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Articles in Mother Earth News

I have an article coming up in the Mother Earth News magazine, about making and using open wood flats for seedlings and transplants. I also contribute to their blog, in the Organic Gardening section.

Collard Greens are having their Own Week!

Collards are a southern food icon and an underappreciated nutrition powerhouse that has sustained generations of southerners, both Black and white. At last this vegetable is getting the recognition it deserves! The first ever Collards Week is happening December 14-17 2020. I found out about this while researching for an article on collards for Growing for Market magazine. Yes, perhaps the title “Week” is aspirational, and four days is a jumping-off point for the post-Covid future.

There will be online presentations celebrating collards led by Michael Twitty, Ira Wallace, Jon Jackson, Amirah Mitchell and Ashleigh Shanti. This event includes food history, seed stewardship, gardening, farming, cooking and conversation and is part of the Heirloom Collard Project. Collards Week is a collaboration between the Culinary Breeding Network and The Heirloom Collard Project. You can register for free at www.heirloomcollards.org/collard-week-2020/. All events will be broadcast live through YouTube Live via the Culinary Breeding Network starting at 1:00pm Eastern time.

Chef Ashleigh Shanti preparing collards.
Photo Chris Smith

Michael Twitty’s kick-off presentation, The History and Significance of Collards in the South, will be a fascinating exploration of complex issues. Twitty states this himself on his blog, Afroculinaria, “The collard’s complicated story with African Americans really speaks to the way food can unravel the mysteries of complex identities.”

The Collards Tour and the Book

From 2003 to 2007, a team of four crisscrossed the South, mostly in North and South Carolina, searching for heirloom col­lards by word-of-mouth, by spotting them as they drove past, and by reading newspapers, attending small-town collard festivals, and visiting restaurants where collards were the only greens served. After the trip, USDA Plant Geneticist Mark Farnham grew out more than sixty of the heirloom collard cultivars in a trial garden at a USDA Agricultural Research Station. He published several papers, including the 2007 article “Neglected Landraces of Collard from the Carolinas.”

Two of the other road trip members, Edward H Davis and John T Morgan of Emory & Henry College, wrote a beautiful book: Collards: A Southern Tradition from Seed to Table to tell the stories of these varieties and the gardeners who steward them. Davis and Morgan noted that despite other wide diversity among the collard seed savers, most of them were older, with an average age of 70, and most of them had no family, friends, or neighbors will­ing or able to keep growing their special family collard variety into the future.

The Heirloom Collards Project

In 2016, Seed Savers Exchange in collaboration with Ira Wallace at Southern Exposure Seed Exchange requested over 60 collard varieties from the USDA ARS National Plant Germplasm System (NPGS) to trial at Seed Savers Exchange, Decorah, Iowa. These were rare heirloom varieties collected by Davis and Morgan from seed savers across the Southeast. The goal of the Heirloom Collards Project is to support the tradition of heirloom collards, by finding growers and sharing the seeds nationally and also to celebrate the special stories associated with these heirloom collards.

The Heirloom Collard project is a national program led by Southern Exposure Seed Exchange, Seed Savers Exchange, Working Food and The Utopian Seed Project. The Project is building a coalition of seed stewards, gardeners, farmers, chefs and seed companies to preserve heirloom collard varieties and their culinary heritage.

Ira Wallace has an article “A Southern Food Tradition: Saving Heirloom Collards” coming out in the Jan/Feb 2021 issue of Grit magazine. There she points out that giant seed companies have been buying out the smaller ones, and have reduced the number of open-pollinated collard varieties readily available to only five.  Saving heirloom collards is an act in food heritage. Ira’s article also includes some collard stories and directions for growing seed. You can also find good directions for growing seed in Jeff McCormack’s Organic Brassica Seed Production Manual.

Mosaic photo by Chris Smith

The Heirloom Variety Trial

The National Heirloom Collard Variety Trial was launched in 2020, with over 230 participants across the US. They are currently growing twenty different varieties from the large collection at Seed Savers Exchange and the USDA. This collection includes varieties from the Davis and Morgan collecting trips. There are eight trial sites growing all 20 varieties and also hundreds of citizen scientists growing and comparing randomly selected sets of three varieties. The growers are recording data for each collard variety on appearance, uniformity, vigor, disease resistance, flavor, germination, earliness, yield and winter hardiness. Their data will be recorded and analyzed via SeedLinked, a web platform connecting people with information on varieties written by people growing them.

The Heirloom Collard Project has a place for everyone interested in growing or eating this delicious vegetable, including home gardeners, experienced seed savers, commercial growers and chefs. Click the link to see photos of the 2020 varieties and the farms doing the full trial. Get ready to sign up for 2021. Novice seed growers may want to consider practicing with more common varieties first, and then, as they gain experience, they can sign up to become seed-saving stewards.

Morris Heading collards.
Photo Kathryn Simmons

Growing collards

Collards are very easy to grow and harvest, providing months of harvests from a single sowing. They are cold-hardy and heat-tolerant, giving the possibility of harvests ten months of the year in the Southeast. Colder areas may need to provide some protection if wanting mid-winter harvests. Hotter areas may need a longer summer break. Growers can make sauerkraut to extend the season. There is a wide range of leaf shapes and colors including variegated types. For details of how to grow collards, see my article coming soon in Growing for Market.

Collard stecklings overwintering in a pot for seed saving.
Photo Seed Savers Exchange

There is a fascinating  blog post  published on the Heirloom Collard website written by Norah Hummel, who is a Seed Savers Exchange partner in the Heirloom Collards Project. It’s a really fantastic blog post with some really good photographs, talking you through the whole process of growing collard seed.

Growing Collard Seed

Like other brassicas, collards are a biennial seed crop. To save seed, keep your collard plants alive over winter. If you can’t do this outdoors or in a hoophouse, dig up the plants in late fall and trim off the leaves, preserving the growing point. Replant these plant stubs (stecklings) close together in a tub of soil or even damp sawdust, to replant in early spring. Make sure you have no other brassicas from the oleracea group (Brussels sprouts, cabbage, cauliflower, some kales, kohlrabi) in flower at the same time. Some kales (Russian, Siberian types) are Brassica rapa and do not cross-pollinate.

Winnowing collard seed with a box fan.
Photo Southern Exposure Seed Exchange

Read Margaret Roach’s interview on A Way to Garden, with Chris Smith of Utopian Seed Project, a crop-trialing nonprofit working to celebrate food and farming, and Sow True Seeds, talking about heirloom collards.

Vegetable harvests, articles on seed saving and garlic planting, workshop on cover crops.

 

Close up of Cow Horn okra pods.
Photo Kathryn Simmons

There are several aspects of vegetable harvesting. In this post I will look first at maturity indicators, then at four ranges of cold-hardy crops for harvest at various stages of winter, followed by a reminder of the order for harvesting storable crops, according to the coldest temperature they can take. After that I have links to a couple of other websites with great information on these topics, a mention of two articles on seed saving  and one on garlic planting I have in Growing for Market magazine. And a link to a Mother Earth News Fair Online workshop on establishing winter cover crops.

Harvest and Maturity Indicators

Don’t harvest too soon or too late. How do you know when it’s ready to harvest? Different factors are important for different crops. Use all your senses.

  • Size: Cow Horn okra at 5”/13 cm (others shorter), green beans a bit thinner than a pencil, carrots at whatever size you like, 7”/18 cm asparagus, 6”/15 cm zucchini
  • Color: Garden Peach tomatoes with a pink flush. The “ground spot” of a watermelon turns from greenish white to buttery yellow at maturity, and the curly tendrils where the stem meets the melon to turn brown and dry. For market you may harvest “fruit” crops a bit under-ripe
  • Shape: cucumbers that are rounded out, not triangular in cross-section, but not blimps. Sugar Ann snap peas get completely round before they reach peak sweetness.
  • Softness or texture: eggplants that “bounce back” when lightly squeezed, snap beans that are crisp with pliable tips. Harvest most muskmelons when the stem separates easily from the fruit (“Full slip”).
  • Skin toughness: storage potatoes when the skins don’t rub off, usually two weeks after the tops die, whether naturally or because of mowing.
  • Sound: watermelons sound like your chest not your head or your belly when thumped. Try the “Scrunch Test” – press down firmly on the melon and listen and feel for the separation of the ripe flesh inside the melon.

Cabbages are fully mature when the head is firm and the outer leaf on the head is curling back. Ignore the separate “wrapper leaves” when making this judgment. If you need to keep mature cabbage in the ground a few days longer, twist the heads to break off some of the feeder roots and limit water uptake, and they will be less likely to split.

Mature cabbage showing curled leaf on the head.
This educational photo of a split cabbage is provided by Firesign Farm

Broccoli
Select blue-green broccoli heads and harvest them before the flower buds open, but after they’ve enlarged. We press down with finger-tips and spread our fingers to see if the head is starting to loosen.

Young immature broccoli head after rain
Photo Wren Vile

Sweet Corn

Sweet corn will be ready to harvest about three weeks after the first silks appear. Corn is ready when the ears fill to the end with kernels and the silks become brown and dry. An opaque, milky juice will seep out of punctured kernels. You can use your thumbnails to cur through the husk on the side and view the kernels. Don’t make your cut on top of the ear, or the dew and rain will get in and rot the corn.

Sweet corn ears are mature when the silks die and turn brown. Photo Kathryn Simmons
Mature Sweet corn ear.

Garlic

Garlic is ready to harvest when the sixth leaf down is starting to brown on 50% of the crop. See Ron Engeland’s Growing Great Garlic. Harvesting too early means smaller bulbs (harvesting way too early means an undifferentiated bulb and lots of wrappers that then shrivel up). Harvesting too late means the bulbs may “shatter” or have an exploded look, and not store well.

Cut across hardneck garlic – airspaces around the stem show maturity

Music garlic cut open showing gaps around stem – a sign of maturity.
Photo Southern Exposure Seed Exchange
Garlic bulb cut horizontally to check maturity (good now or soon).
Photo Wren Vile

Onions

Wait until the tops fall over to harvest, then gently dig up the whole plant and dry. Leave the dry, papery outer skin on the onion for protection.

Onions curing and drying in strings. Photo by Southern Exposure Seed Exchange

Four Ranges of Cold-Hardy Crops for Harvest at Various Stages of Winter

  1. Crops to keep alive into winter to 22°-15°F (-6°C to -9°C), then harvest. Harvest and use soon: Asian greens, broccoli, cabbage, chard, lettuce, radishes. Harvest and store: beets, cabbage, carrots, celeriac, kohlrabi, winter radish (including daikon), rutabagas, turnips. Many greens and roots can survive some freezing, so it is worth experimenting to find how late you can keep crops outdoors.
  2. Hardy winter-harvest crops: cabbage (Deadon), carrots, collards, kale, leeks, parsnips, scallions, spinach. We grow our winter-harvest crops in our raised bed area, which is more accessible in winter and more suited to small quantities.
  3. Overwinter crops for spring harvests before the main season. Some crops, if kept alive through the winter, will start to grow again with the least hint of spring weather and be harvestable earlier than spring plantings. Depending on your climate, the list can include carrots, chard, chicories such as radicchio and sugarloaf, chives, collards, garlic, garlic scallions, kale, lettuce, multiplier onions (potato onions), scallions, spinach. In mild areas, peas can be fall sown for a spring crop. Sow 1″ (2.5 cm) apart to allow for extra losses.
  4. Winter hoophouse crops: The rate of growth of cold-weather crops is much faster inside a hoophouse than outdoors. The crop quality, especially with leafy greens, is superb. Plants can tolerate lower temperatures than outdoors; they have warmer soil around their roots, and the pleasant daytime conditions in which to recover. Salad greens in a hoophouse can survive nights with outdoor lows of 14°F (–10°C) without inner rowcover.

In my post Root Crops in October, I gave this list of storable crops in the order for harvesting, related to how cold they can survive.

Clear and store (in this order):

  • Sweet potatoes 50°F (10°C)
  • “White” Peruvian potatoes 32°F (0°C) approximately
  • Celeriac 20°F (°C)
  • Turnips 20°F (°C)
  • Winter radish 20°F (°C)
  • Beets 15-20°F (°C)
  • Kohlrabi, 15°F (°C)
  • Carrots 12° F (°C)
  • Parsnips 0°F (°C)

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Here are some links to a couple of good sources for more harvest information:

  1. Piedmont Master Gardeners Garden Shed Newsletter

Guidelines for Harvesting Vegetables by Pat Chadwick

A list of seven basic principles of harvesting, followed by a crop-by-crop list of almost 50 individual crops and a resource list of 18 publications (focused on the mid-Atlantic and Southeast)

  1. October Tips from Harvest to Table, by Steve Albert covers all climate zones and comes complete with a USDA Hardiness Zone Map

Prepare your garden for colder weather, plant winter crops where there is still time, harvest crops that will suffer from cold, construct low tunnels with rowcover or clear plastic to keep crops somewhat protected from wind and cold temperatures

Links to other posts by Steve Albert

How to Prepare a Winter Vegetable Garden

Predicting Frost in the Garden

Garden Tips for October


Growing for Market articles

Harvesting seeds this fall?

I have written articles for Growing for Market magazine about growing and saving seeds (August and September issues), and planting garlic (October issue).

Given the shortages of some varieties this spring, it wouldn’t surprise us if more people tried producing seeds of vegetable or flower varieties this year. Here are links to articles from the August and September magazines, covering wet and dry seed processing.

Roma tomatoes cut in half for seed extraction.
Photo Pam Dawling

Wet seed processing and saving

Wet seeds are embedded in fruit. Wet processing has four steps: scooping out the seeds or mashing the fruit, fermenting the seed pulp for several days, washing the seeds and removing the pulp and then drying the washed seeds.

Read the article “Wet seed processing and saving”

Dry seed processing and saving

Dry seeds develop in pods, husks or ears, and dry on the plant rather than inside a fruit. While you obviously want to get seeds into the hands of growers before they need to plant, and into seed catalogs before they get printed, often there is no urgency to extract the dry-seeded crops from their pods. You can wait for a slower time, or use seed cleaning as a rainy-day job.

Read the article “Dry seed processing and saving”

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Mother Earth News Fair

I have a workshop on Winter Cover Crops for Gardeners as part of the Mother Earth News Fair Online Winter Gardening Course. The Winter Gardening Course features 7 videos, each 21-44 minutes long. Mine’s 32 minutes on cover crops.

You can enroll for the 8-course Winter Gardening Course for $20.

Or choose the 2020 all-access course bundle of 21 courses (over 100 videos) for $150.

 

 

 

 

 

 

 

 

 

 

My recent work in Growing for Market, Mother Earth News and pepper research

Seed saving and processing

August 2020 Growing for Market magazine

Heads up everyone saving seed from their tomatoes, melons, or squash this year, in anticipation of possible seed shortages next spring! Or because you have the time at home to figure out how to do it, and you’re around to stir the bucket three times a day! I have an article on wet seed processing in the August issue of Growing for Market magazine.

Roma tomatoes cut in half for seed extraction.
Photo Pam Dawling

Also see my post on washing and drying tomato seeds, with lots of photos.

The next issue will have my article on dry seed processing (think beans, peas, okra, lettuce).

The current issue also has a couple of interesting articles on how to move step-by-step towards no-till growing, or at least minimum-till. Many gardeners and farmers have floundered while making this transition, so learn from the experienced! And there’s an article by Julia Shanks on balance sheets, for those intending to make a living farming.


Winter Cover Crops for Gardeners

A no-till cover crop mix of winter rye, hairy vetch, Austrian winter peas and crimson clover.
Photo Bridget Aleshire

I have a workshop on Winter Cover Crops for Gardeners as part of the Mother Earth News Fair Online Winter Gardening Course. The Winter Gardening Course features 7 videos, each 21-44 minutes long. Mine’s 32 minutes on cover crops.

You can enroll for the 8-course Winter Gardening Course for $20.

Or choose the 2020 all-access course bundle of 21 courses (over 100 videos) for $150.

Or before summer is over, go for the $120, 8 course (56 videos) Summer Bundle.

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What went wrong with our hoophouse peppers in 2020?

Diseased hoophouse pepper plant.
Photo Pam Dawling

Our 2020 hoophouse peppers were stunted, crinkled, yellowing and failed to thrive.

Possibilities:

  1. Too cold in edge bed A (drafts under baseboard)?
  2. Too wet in bed A (rainwater under baseboard, not much drying out due to shade of tomatoes)?
  3. Nutsedge poisoning: roots exude something that inhibits other plants?
  4. Soil too salty?
  5. Soil nutrients poor?
  6. Aphids
  7. Aphids spread a virus? (plants were crinkled)
  8. Are we sowing hoophouse peppers too early? In cells that are too big?
  9. Are we transplanting hoophouse peppers too early? Keeping them in in cells that are too small?

Possible solutions

  1. Be sure to block drafts all winter. Try not to plant peppers in cold edge beds.
  2. Close one row of driptape if soil in edge bed A seems excessively wet compared to other beds. Re-dig outside moat to keep soil water out.
  3. Do better about weeding out nutsedge. Investigate soil properties that encourage nutsedge.
  4. Use beds C and E instead of middle bed D when doing salt water wash down. Poke out holes in sprinkler, ensure all are working. Get a better sprinkler.
  5. Do soil tests in October and remediate soil as needed.
  6. We could monitor for pests and act promptly
  7. Deal with aphids and avoid viral diseases
  8. Sow later, in smaller cells.
  9. Transplant later, after potting up to bigger cells or pots.

Summary of ideas after our meeting and reading 2020 records:

  • Use fresh seed
  • Go back to deep 6 cells for sowing, (smaller than R38)
  • Use more appropriately warm growing conditions. Peppers don’t recover well from setbacks. They remain stunted long term.
  • Test soil and act accordingly.
  • Ensure salt wash-down reaches the edge beds.
  • If planting in chilly edge beds, ensure the baseboards are not drafty.
  • Don’t overwater.
  • Remove nutsedge whenever we see it
  • Monitor for pests; deal with aphids to avoid long-term virus diseases.
Pepper plant with aphids. Photo Pam Dawling

Hoophouse Pepper Records Research

  • We have been sowing 2/3 for a 4/7 transplant date. That’s maybe too long. 9 weeks.
  • 2/3/20 Hphs peppers sown as scheduled. Used R38s rather than usual deep 6s. It’s recommended not to sow peppers in large cells – they are slow growing, and it’s hard to get the watering right in large cells.
  • 2/11 -2/14 Peppers germinated. We had some trouble with keeping the germinating chambers up to temperature because we didn’t have the right lightbulbs.
  • 2/15 – 2/17 Heat mats not all plugged in or working right.
  • 2/21 resowed Gilboa. PeaceWork was old seed, poor vigor? Or low germ rate?
  • 2/28 Gilboa resows had been in tent but weren’t actually germinated. Back in fridge.
  • 3/4 – 3/9 Potted up. Is this true? R38s don’t normally get potted up. Maybe due to patchy germination?
  • 3/16 In ghs drafty zone
  • 4/5 Ghs door left open all night
  • 4/12 Ghs door left open all night again.
Hoophouse peppers in a better year!
Photo Pam Dawling

Info from Sustainable Market Farming  and The Year-Round Hoophouse

  • Sow 8-10 weeks before you intend to transplant.
  • We used to sow our hoophouse peppers 1/17, then 1/24, then 1/31, then 2/3.
  • Minimum temperature for germination is 60F, optimum 68-95F.
  • Peppers seem to produce stockier plants if soil temperatures are 65-68F, max 80F daytime, min 60F at night after germination. Use a soil thermometer.
  • Transplants getting slightly cooler nights will grow sturdier plants that flower later and have more potential for big yields. Rowcover at night if 40F or below.
  • After third true leaf, can reduce night temp to 54F. May increase yields.
  • But, permanently stunted by conditions that are too cold.
  • Keeping them in pots or cells that are too small will set them back. If transplanting is delayed, pot up to larger size, eg tomato pots.
  • Pot up when a few true leaves appear. After that no heat mat needed.
  • We moved our transplanting date from 4/1 to 4/7 (one week after tomatoes is usual)
  • Transplant at 6-9 weeks, with 4 or 5 true leaves, not yet flowering. OK if they are big.
  • Soil for transplanting should be at least 60F, ideally 68F
  • Avoid transplant shock. Soil needs to be damp before, during and after transplanting. Avoid root damage or bending. Shade if hot, sunny or breezy.
  • For the first week after transplanting, keep warm.
  • Established peppers benefit from 70-75F days, 64-68F nights
  • Maintain sufficient levels of boron, calcium, phosphorus.
  • Monitor and control aphids and thrips to prevent the diseases they vector.
  • An inch of water per week is about right.
  • Foliar feeding with fish or seaweed emulsion once a week after fruit set.
  • 65-80 days from transplant to full-size immature fruits, and another 2-4 weeks to ripe fruit.
  • Yields should be 5-18 lbs/10ft.

Ideas after rereading those sources

  • We might do better to set the sowing date a week later (2/10), keep the transplant date at 4/7 and aim for an 8 week-old transplant? (Avoid colder conditions)
  • We need to pay more attention to temperatures of germination, seedlings and potted transplants. Write the goal temperatures on the Seedlings Schedule
  • We need to pay more attention to not overwatering seedlings. Write that on the Seedlings Schedule too.

Growing and Saving Seeds: my Seed Garden Slideshow and a Cuban Bean Seed Bank

 

At the Organic Growers School Spring Conference I gave my presentation The Seed Garden, about combining growing some seed crops alongside lots of vegetable crops – a way for vegetable growers to diversify and grow seed of a few special crops either for themselves or to sell for some extra income and to keep a chosen variety available. I included information on selecting desirable characteristics and making an improved strain of that variety.

You can watch the slideshow here, by clicking on the diagonal arrow to increase the screen size and then the right pointing triangular arrow:

I also took the opportunity to add a few more of my slideshows to my collection on SlideShare.

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Meanwhile I’ve been sorting out more photos from my Cuba trip, and I want to tell you about a bean seed bank at Finca Hoyo Bonito I visited during our day traveling from Havana, west for three hours to the Viñales Valley in the province of Pinar del Rio.

The seed farm has a bank containing 250 varieties of bean seed. It’s a hobby for the retired woman growing and saving the beans. Her goal is to get a hundred pounds of each variety. She gives bean seed to any farmer who asks, with no requirement to return the investment. (this is different from some seed banks, which require growers to repay the “loan”)

Finca Hoyo Bonito bean seed bank, Pinar del Rio, Cuba
250 bean seed varieties are kept in this tiny seed bank.
The Seed Conservator, or Banker at Finca Hoyo Bonito. Note the reuse of ubiquitous plastic water bottles to store some of the seeds. Tourists need to drink only bottled water.
Bean seed has a limited shelf life, and so must be grown out frequently.
Here is a display of just some of the bean varieties.
Finca Hoyo Bonito Bean Seed Bank, Pinar del Rio, Cuba

Here is a short video about Finca Hoyo Bonito. It’s in Spanish, naturally!

Winter-Kill Temperatures of Cold-Hardy Vegetables 2020

Overwintered Vates kale in central Virginia in March.
Photo Nina Gentle

At the Organic Association of Kentucky Conference, I gave a a presentation on Winter High Tunnel and Outdoor Vegetable Production. You can see it here. Click on the diagonal arrow icon to see it full screen, then click on the right pointing triangular arrow

Winter-Kill Temperatures of Cold-Hardy Vegetables 2020

I keep records of how well our crops do in the colder season, both outdoors and in our double-layer hoophouse. I note each increasingly cold minimum temperature and when the various crops die of cold, to fine-tune our planning for next year. We are in zone 7a, with an average annual minimum temperature of 0-5°F (-18°C to -15°C). 

The winter 2019-2020 has been mild, with our lowest temperature being a single night at 12°F (-11°C). The Koji became completely unmarketable but did not completely die. Yukina Savoy is indeed hardier, being OK down to 10°F (-12°C). We had one night at 13°F (-10°C) and two each at 17°F (-8°C), 18°F (-8°C also) and 19°F (-7°C).

This winter I noted the death of rhubarb stems and leaves at 25°F (-4°C), rather than 22°F (-6°C), as I noted a year or two ago.

In early January 2018, we had some extremely cold temperatures of -8°F and -9°F (-22°C and -23°C). The winter of 2018-2019 was not as brutal. Our lowest temperatures were 6°F (-14°C) in late January, 8°F (-13°C) in December 2018 and a couple of 11°F (-12°C). I found that senposai is more cold-tolerant than I had thought. Averaging our winter low over those three winters gives 3.2°F (-16°C), completely within the zone 7a range.

My other results from other years still hold up.

I also learned that there is more damage when the weather switches suddenly from warm to cold. And that the weatherman in Raleigh, NC says it needs 3 hours at the critical temperature to do damage.

Radicchio seeds from Seeds from Italy

Notes on Chicories and Endives

We gave up growing chicories and endives because we really didn’t like the bitterness. I decided to do some more online research to make sure I wasn’t spreading untruths. Chicories and endives fall into two groups, but they are confusing because the common names sometimes suggest the opposite group than they are botanically. Here’s the best info I have. If you know differently, please leave a comment.

Cichorium intybus, commonly called chicories, are mostly heading crops. The group includes radicchio, both Treviso and Chioggia (hardy to about 20°F (-7°C). Belgian Witloof endive (the kind for forcing chicons) is also a chicory. It dies at 25°F (-4°C). Sugarloaf chicory is the least hardy chicory, and dies at 27°F (-3°C).

Cichorium endivia, commonly called endives, are mostly loose-leaf crops, less cold-hardy than intybus types (chicories). This group includes Frisée types and escaroles, which are also known as Batavian endives. They generally survive down to 22°F (-6°C), although Perfect and President endives can survive down to 10°F (-12°C) – can anyone confirm or deny this?

Using the List

Unless otherwise stated, these are killing temperatures of crops outdoors without any rowcover. All greens do a lot better with protection against cold drying winds. Note that repeated cold temperatures can kill crops that can survive a single dip to a low temperature, and that cold winds, or cold wet weather can destroy plants quicker than simple cold. Your own experience with your soils, microclimates and rain levels may lead you to use different temperatures in your crop planning.

Hoophouse beds in November.
Photo Ethan Hirsh

Hoophouse Notes

Our double-plastic hoophouse keeps night time temperatures about 8F (4.5C) degrees warmer than outdoors, sometimes 10F (5.5C) degrees warmer. Plus, plants tolerate lower temperatures inside a hoophouse. The soil stays warmer; the plants recover in the warmer daytime conditions (it seems to be the night+day average temperature that counts);

In the hoophouse (8F (4.5C) degrees warmer than outside) plants without extra rowcover can survive 14F (7.7C) degrees colder than they could survive outside; with thick rowcover (1.25oz Typar/Xavan) at least 21F (11.6C) degrees colder than outside.

For example, salad greens in our hoophouse can survive nights with outdoor lows of 14°F (-10°C). Russian kales, lettuce, mizuna, senposai, spinach, tatsoi, turnips, Yukina Savoy survived a hoophouse temperature of 10.4°F (-12°C) without rowcover, -2.2°F (-19°C) with. Bright Lights chard got frozen leaf stems.

Young Bright Lights chard.
Photo Pam Dawling

Lettuce varieties for a solar-heated winter greenhouse or hoophouse in zone 7a: (hardiest are in bold) Buckley, Ezrilla, Green Forest, Green Star, Hampton, Hyper Red Rumpled Wave, Marvel of Four Seasons, Merlot, New Red Fire, North Pole bibb, Oscarde, Outredgeous, Pirat, Red Cross bibb, Red Sails, Red Salad Bowl, Red Tinged Winter, Revolution, Rouge d’Hiver, Salad Bowl, Sylvesta bibb, Tango, Winter Marvel, Winter Wonderland.

Outdoor killing temperatures of crops (unprotected unless stated)

35°F (2°C):  Basil.

32°F (0°C):  Bush beans, some cauliflower curds, corn, cowpeas, cucumbers, eggplant, limas, melons, okra, some pak choy, peanuts, peppers, potato vines, squash vines, sweet potato vines, tomatoes.

27°F (-3°C): Many cabbage varieties, Sugarloaf chicory (takes only light frosts).

25°F (-4°C): Some cabbage, chervil, Belgian Witloof chicory roots for chicons, and hearts, Chinese Napa cabbage (Blues), dill (Fernleaf), some fava beans (Windsor), annual fennel, some mustards (Red Giant, Southern Curled) and Asian greens (Maruba Santoh, mizuna, most pak choy, Tokyo Bekana), onion scallions (some are much more hardy), radicchio, rhubarb stems and leaves.

Tokyo bekana in our hoophouse.
Photo Twin Oaks Community

22°F (-6°C): Some arugula (some varieties are hardier), Bright Lights chard, endive (Escarole may be a little more frost-hardy than Frisée), large leaves of lettuce (protected hearts and small plants will survive colder temperatures).

20°F (-7°C): Some beets (Bulls Blood, Chioggia,), broccoli heads (maybe OK to 15°F (-9.5°C)), Brussels sprouts, some cabbages (the insides may still be good even if the outer leaves are damaged), some cauliflower varieties, celeriac, celtuce (stem lettuce), some head lettuce, some mustards/Asian greens (Tendergreen, Tyfon Holland greens), flat leaf parsley, radicchio, both Treviso and Chioggia, radishes (Cherry Belle), most turnips (Noir d’Hiver is the most cold-tolerant variety).

Large oat plants will get serious cold damage. Oats seedlings die at 17°F (-8°C)

Canadian (spring) field peas are hardy to 10-20°F (-12 to -7°C).

15°F (-9.5°C): Some beets (Albina Verduna, Lutz Winterkeeper), beet leaves, some broccoli, some cabbage (Kaitlin, Tribute), covered celery (Ventura), red chard, cilantro, fava beans (Aquadulce Claudia), Red Russian and White Russian kales, kohlrabi, some lettuce, especially medium-sized plants with 4-10 leaves (Marvel of Four Seasons, Olga, Rouge d’hiver, Tango, Winter Density), curly leaf parsley, rutabagas (American Purple Top Yellow, Laurentian), broad leaf sorrel, most covered turnips, winter cress.

Young Cylindra beets.
Photo Wren VIle

12°F (-11°C): Some beets (Cylindra,), some broccoli perhaps, Brussels sprouts, some cabbage (January King, Savoy types), carrots (Danvers, Oxheart), most collards, some fava beans (mostly cover crop varieties), garlic tops if fairly large, Koji greens, most fall or summer varieties of leeks (Lincoln, King Richard), large tops of potato onions, covered rutabagas, some turnips (Purple Top).

10°F (-12°C): Covered beets, Purple Sprouting broccoli for spring harvest, a few cabbages (Deadon), chard (green chard is hardier than multi-colored types), some collards (Morris Heading can survive at least one night at 10F), Belle Isle upland cress, some endive (Perfect, President), young Bronze fennel, Blue Ridge kale, probably Komatsuna, some leeks (American Flag, Jaune du Poiteau), some covered lettuce (Pirat, Red Salad Bowl, Salad Bowl, Sylvesta, Winter Marvel), covered winter radish (Daikon, China Rose, Shunkyo Semi-Long survive 10°F/-12°C), Senposai leaves (the core of the plant may survive 8°F/-13°C), large leaves of savoyed spinach (more hardy than smooth-leafed varieties), Tatsoi, Yukina Savoy.

Oats cover crop of a medium size die around 10°F (-12°C). Large oat plants will die completely at 6°F (-17°C) or even milder than that.

5°F (-15°C): Garlic tops even if small, some kale (Winterbor, Westland Winter), some leeks (Bulgarian Giant, Laura), some bulb onions, potato onions and other multiplier onions, smaller leaves of savoy spinach and broad leaf sorrel. Many of the Even’ Star Ice Bred greens varieties are hardy down to 6°F (-14°C), a few unprotected lettuces if small (Winter Marvel, Tango, North Pole, Green Forest).

Garlic shoots in January.
Photo Pam Dawling

0°F (-18°C): Chives, some collards (Blue Max, Winner), corn salad (mâche), garlic, horseradish, Jerusalem artichokes, Even’ Star Ice-Bred Smooth Leaf kale, a few leeks (Alaska, Durabel, Tadorna); some bulb onions, yellow potato onions, some onion scallions, (Evergreen Winter Hardy White, White Lisbon), parsnips (probably even colder), salad burnet, salsify (?), some spinach (Bloomsdale Savoy, Olympia). Walla Walla onions sown in late summer are said to be hardy down to -10°F (-23°C), but I don’t trust below 0°F (-18°C)

Crimson clover is hardy down to 0°F (-18°C) or slightly colder

 -5°F (-19°C): Leaves of overwintering varieties of cauliflower, Vates kale survives although some leaves may be too damaged to use.

-10°F (-23°C) Austrian Winter Field Peas and Crimson clover (used as cover crops).

-15°F (-26°C) Hairy vetch cover crop – some say down to -30°F (-34°C)

-20°F (-29°C) Dutch White clover cover crops – or even -30°F (-34°C)

 -30°F to -40°F (-34°C to -40°C): Narrow leaf sorrel, Claytonia and some cabbage are said to be hardy in zone 3. I have no personal experience of this.

 -40°F (-40°C) Winter wheat and winter rye (cover crops).

Alamar Urban Organic Farm

I mentioned before that I took part in the Organic Growers School Cuba Agroecolgy Tour in January. I’ve made some progress sorting through my photos, and this post is about Organopónico Vivero Alamar (Alamar Urban Organic Farm) on the outskirts of Havana. Alamar is one of the largest and most successful urban farms in Havana, and it is very impressive. It was founded in 1997.

Alamar Urban Organic Farm, Havana, Cuba

During the Special Period in Time of Peace in Cuba (1991-2000), an extended period of economic hardship following the collapse of the Soviet Union combined with a US trade blockade, Cubans were thrown back on their own resources.  This was described to me as “Cuba went to bed with privilege and woke up with nothing.” Food, fuel and equipment were not imported, and people began producing food wherever they could. Because there were no fertilizers or pesticides, vegetables and fruit were grown organically. In time, Cubans came to see the superiority of organic farming, and today the urban farms and small-scale food-producing farms continue to be organic (Cuban organic standards are not the same as USDA requirements). Commodity crops (tobacco, coffee, sugar) however, are not usually organically grown.

Farm manager and educator Isis with a lettuce plug

Alamar Urban Organic Farm covers 11 hectares (27 acres) in a residential dormitory suburb, surrounded by  grey prefabricated concrete apartment blocks in the classic Soviet style. Like many Cuban farms, there are many and varied tropical tree fruits, and permaculture is easily practiced. Sadly, it wasn’t mango season when I visited, although early-ripening mango varieties were in flower. Here is a fruit tree I lost the name of:

Alamar and other organic farms have many tree fruits. I forgot the name of this one

Alamar has 125 workers, with an average age in the “upper middle age” bracket. They produce vegetables and ornamental plants for sale, as well as medicinal and spiritual plants. 90% of their sales are to the public and 10% to hospitals.  The Cuban government ensures that hospitals and schools get provided for, I think. They keep bulls (steers?) and rabbits for manure, and oxen and horses for cultivation. Rabbit meat is not popular.

A large screen house at Alamar Organic Farm

Many of the crop plants are inside shade and/or screen houses, which took quite a hit from Hurricane Irma. Agricultural buildings are mostly pole barns thatched with leaves of the Royal Palm. Thus they can be rebuilt after hurricanes destroy them.

A large shade house for landscape plants at Alamar Urban Organic Farm

Vegetables are on raised beds. Almost all seed has to be imported and is not organic. Cubans we spoke with generally thought the humid climate would be too hard for seed growing. Personally, I wonder if that’s true. I think a home-grown seed business would be a good step towards more food sovereignty, but it’s not for me to say, really!

Alamar makes their own potting soil from 50% humus, 25% compost and 25% rice hulls. Cubans eat a lot of rice, and annually import 300,000 tons of cheap Vietnamese  rice which needs a lot of cleaning.

Alamar urban organic Farm vegetable beds

Alamar is trialing biochar as animal bedding, to reduce smell, and charge the biochar with nutrients and micro-organisms before it is used on the fields. They have insectary plantings (flowering plants to attract beneficial insects and birds) at the heads of many vegetable beds. They use mung beans as a cover crop and to grow bean sprouts.

Hot climate version of oregano at Alamar Urban Organic farm

The tropical “oregano” in the photo above looks nothing like our temperate climate oregano. It is almost a succulent, and the leaves are much bigger than we are used to .

Alamar has tried growing mushrooms, but they are not commonly eaten in Cuba. They also make value-added products: condiments, garlic paste, tomato sauce and pickles.  Canning is not easy, as glass canning jars are not available and there are regulations against plastic jars.

Beautiful bed of pak choy at Alamar Urban Organic Farm
Large shade house and vegetable beds at Alamar Urban Organic Farm

They make for use and sale both compost and vermicompost. Below are two photos of open air concrete worm bins, which they cover with tarps.

Alamar Farm manager Isis shows us some of their worm bins
Large worm bins under shade at Alamar Urban Organic Farm

Alamar also has a Beneficial Insect Breeding Laboratory.  Click the link to watch a short video.

Alamar Urban organic Farm has its own Beneficial Insect Rearing Lab

Another source of income for Alamar is workshops and courses in organic agriculture and tours such as ours. Cuba geared up for a big increase in American tourists during the Obama administration but has seen fewer tourists since Trump introduced stricter criteria for Americans visiting Cuba.

There are several types of agricututal co-operatives in Cuba. Alamar is a Unidad Básica de Producción Cooperativa (Basic Unit of Cooperative Production). In 1993, the Cuban state handed over agricultural land to co-operatives “in usufruct”, which means “the right to enjoy the use and advantages of another’s property short of the destruction or waste of its substance.”

My Cuba farming trip. Conference season!

I’ve just got back from a wonderful Agroecology Tour of Cuba with the Organic Growers School. Click the link to sign up for the 2021 tour. I have lots of photos and much to say, but so little time today! In 9 days we visited 9 farms, had several speakers address aspects of life (and particularly farming and environmental issues) in Cuba, had a couple of walking tours, ate many delicious farm-to-table type dinners and still had time for a salsa lesson

We are having trouble with our internet connection today, so this post will either be short or very short.


I’m headed to the Little Rock, Arkansas conference of the Southern Sustainable Working Group

Go to my Events Page for a full list of where to look for me. Not long after getting home from SSAWG I’m headed to PASA in Lancaster, Pennsylvania

Then the West Virginia Small Farms Conference

Then OAK, in Louisville, Kentucky,

Then Organic Growers School in Mars Hill, North Carolina

Conferences and Cover Crops

Conferences

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

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

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

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

Cover Crops for Vegetable Growers

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

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

Yukina Savoy
Photo Wren Vile

Optimize your Asian Greens Production

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

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

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

Winter Cover Crops

 

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

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

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

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

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

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

 

Sustainable Market Farming on sale.
Photo Ken Bezilla

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

 

 

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