Alliums for November: Plant garlic, sow onions in a hoophouse, eat leeks

Tadorna winter leeks in October.
Photo Pam Dawling

Cold-Tolerance of Alliums

Alliums are more cold-tolerant than most people believe. Here are my observations of killing temperatures for outdoor crops. Note that crops often survive night-time lows in the hoophouse that would have killed them outdoors.

  • 12°F (−11°C): garlic tops if fairly large, most fall or summer varieties of leeks (Lincoln,King Richard), large tops of potato onions
  • 10°F (−12°C) some leeks (American Flag aka Musselburgh and Scottish Flag, Jaune du Poiteau)
  • 5°F (−15°C): garlic tops if still small, some leeks (Bulgarian Giant, Laura, Tadorna, Bandit), some bulb onions, potato onions and other multiplier onions
  • 0°F (−18°C): chives, garlic, a few leeks (Alaska, Durabel); some bulb onions, yellowpotato onions, some onion scallions (Evergreen Hardy White, White Lisbon), Walla Walla onions sown in late summer (with rowcover for winter)

Planting Garlic

Planting garlic.
Photo Brittany Lewis

You can see my garlic slideshow for more info. I was surprised to find I haven’t written much in my blog about planting garlic, so here goes! See the alliums chapter in Sustainable Market Farming for more on types, varieties, and garlic genetics. The information here comes form that chapter.

When to Plant Garlic

Plant when the soil temperature at 4″ (10 cm) deep is 50°F (10°C) at 9 am. If the fall is unusually warm, wait a week. Instructions from Texas A&M say less than 85°F (29°C) at 2″ (5 cm) deep. We plant in early November. In New Hampshire, mid-October is the time. The guideline for areas with cold winters is 2-3 weeks after the first frost but before the ground freezes solid for the winter. In Michigan, planting time is 6 weeks prior to the ground freezing, giving enough time for root growth only, to avoid freezing the leaves. In California, garlic can be planted in January or February.

Both hardneck and softneck garlic do best when planted in the fall, though softneck garlic may also be planted in the very early spring if you have to (with reduced yields). If you miss the window for fall planting, ensure that your seed garlic gets 40 days at or below 40°F (4.5°C) in storage before spring planting, or the lack of vernalization will mean the bulbs will not differentiate (divide into separate cloves).

Garlic shoots emerging from the mulch a few weeks after November planting. Photo Twin Oaks Community

Garlic roots will grow whenever the ground is not frozen, and the tops will grow whenever the temperature is above 40°F (4.5°C). In colder areas the goal is to get the garlic to grow roots before the big freeze-up arrives, but not to make top growth until after the worst of the weather. In warmer areas, the goal is to get enough top growth in fall to get off to a roaring start in the spring, but not so much top growth that the leaves cannot endure the winter. If garlic gets frozen back to the ground in the winter, it can regrow and be fine. If it dies back twice in the winter, the yield will be lower than it might have been if you had been luckier with the weather. When properly planted, it can withstand winter lows of –30°F (–35°C). If planted too early, too much tender top growth happens before winter. If planted too late, there will be inadequate root growth before the winter, and a lower survival rate as well as smaller bulbs.

How Much Garlic to Plant

A yield ratio of 1:6 or 7 seems typical, and makes complete sense when you consider you are planting one clove to get a bulb of 6–7 cloves. Divide the amount you intend to produce by six to figure out how much to plant. For large areas 750–1,000 lbs/ac (842–1,122 kg/ha) are needed for plantings in double rows, 3″–4″ in-row (7.5–10 cm), beds 39″ (1 m) apart. For single rows, 8 lbs (3.6 kg) of hardneck or 4 lbs (1.8 kg) of softneck plants about 100′ (30 m). In the US, one person eats 3–9 lbs (1.4–4.2 kg) per year.

Popping garlic cloves in preparation for planting
Photo  Southern Exposure Seed Exchange

Popping Garlic Cloves for Planting

The garlic for planting should be taken apart into separate cloves 0–7 days before planting. We are doing this on November 7, along with our crop review meeting when the crew meets to make notes on the past season. This task is a good group activity. Twist off the outer skins and pull the bulb apart, trying not to break the basal plate of the cloves (the part the roots grow from), as that makes them unusable for planting. With hardneck garlic, the remainder of the stem acts as a handy lever for separating the cloves. We sort as we go, putting good size cloves in big buckets, damaged cloves in kitchen buckets, tiny cloves in tiny buckets and outer skins and reject cloves in compost buckets. The tiny cloves get planted for garlic scallions. Don’t worry if some skin comes off the cloves — they will still grow successfully. Cloves for planting should be from large (but not giant) bulbs and be in good condition.

Click the link to read about hot water treatment for seed garlic at WeeBee Farms. 

Pre-plant Seed Garlic Treatments

Many of us do nothing special with the cloves before planting, but if you have pest and disease problems, use pre-plant soaking treatments, usually done the night before planting. Some growers find they get better yields from treated cloves even if no problem was obvious.

To eradicate stem and bulb (bloat) nematode (Ditylenchus dipsaci), soak the separated cloves for thirty minutes in 100°F (37.7°C) water containing 0.1% surfactant (soap). Or soak for twenty minutes in the same strength solution at 120°F (48.5°C), then cool in plain water for 10-20 minutes.

Allow to dry for 2 hours at 100°F (37.7°C) or plant immediately. Anytime your garlic grows poorly and you can’t tell why, send a sample with the soil it’s growing in to your Extension Service to be tested for nematodes. Mites can eat the skins of the cloves, survive the winter and multiply all spring long, seriously damaging or even killing your crop. To kill mites (which hide between the wrappers) before planting, separate the bulbs into cloves and soak them overnight (up to 16 hours) in water.

Possible additions to the water include one heaping tablespoon of baking soda and one tablespoon of liquid seaweed per gallon (around 8 ml baking soda and 4 ml liquid seaweed per liter). Just before planting, drain the cloves and cover them in rubbing alcohol for three to five minutes, long enough for the alcohol to penetrate the clove covers and kill any mites inside. Then plant immediately. The long soaking will loosen the clove skins so that the alcohol can penetrate. Mite-infested garlic soaked like this does much better than unsoaked infested garlic. The solution used to kill mites can also be used to kill various fungal infections. The cloves need only fifteen to thirty minutes soaking.

In trials comparing treated and untreated cloves, treated cloves were larger and healthier than untreated ones. Fusarium levels can be kept down by adding wood ashes when planting and then possibly dusting the beds with more ashes over the winter (use moderation — don’t add so much that you make the soil alkaline). Or you could soak the cloves in a 10% bleach solution, then roll them in wood ash (wear gloves for handling ashy cloves). The wood ash soaks up the dampness of the bleach and provides a source of potassium. This information came from the Garlic Seed Foundation. Join GSF to find out all the details!

Other November Allium Planting

Plant shallot bulbs before the end of November and medium-sized potato onions (1.5″ – 2″, 4-5 cm) at the end of November or early December in zone 7. Finish dividing and replanting perennial leeks and Egyptian walking onions this month

Young onion plant in March.
Photo Kathryn Simmons

Special Allium Topic for November: Sow Bulbing Onions in the Hoophouse

We developed a system of growing onion starts in our hoophouse over the winter and transplanting them bare-root outdoors in very early March. I wrote about choosing onion varieties for your latitude last month. There I explained that to grow big onions we need to have large transplants on March 1, so we can have big vegetative plants before bulbing is triggered by the daylength.

The method involves making two sowings of bulbing onions, each enough for the whole planting. This provides insurance in case one date turns out better than the other. Then we follow this up with a partial third sowing to make up numbers of any varieties that didn’t germinate well. We make our first sowing November 10, our second November 20, and a third on December 5 as a back-up in case of problems. Our formula is: divide the number of onion plants wanted by 20, to give minimum length of row to sow, in feet. And sow this amount twice, 10 days apart. The onions will be planted out at 4″ (10 cm) apart. We add 20% to provide some slack. For a final row of 100′ (30.5 m), we’d need 100′ × 3 per foot × 1.2 (adding 20%) plants. 360 plants. We sow 3 seeds per inch (approx. 1 cm apart), 36 per foot (30 cm). At this sowing rate, we need 120″, or 10′ (3 m).

See The Year-Round Hoophouse for more on growing onions this way. If we find ourselves with extra onion plants in March, we usually re-categorize them as scallions. But we have also transplanted them in early March in a single row along the south edge of hoophouse beds, for an early crop. We got good onions but they dwarfed the pepper plants behind them. Maybe planting them on the north side of the bed is better?

Trimming roots from a leek in December.
Photo Pam Dawling

Storing Leeks

I wrote about how to dig up leeks last month. In zone 7 we leave our leeks in the ground till we need them, being sure to harvest the less hardy Lincoln and King Richard first. We use a walk-in cooler for short term storage (up to a week) and keep the root ends in water. Leeks are best stored at 33°F (0.5°C) and 65% relative humidity. In colder zones, leeks can be harvested and stored in a root cellar or basement. This is helpful in areas where the ground freezes solid for weeks on end. You can store leeks with the roots packed in soil, shoulder to shoulder in a crate or box in a root cellar, where they will keep for six weeks. They can be stored in plastic bags for two to three months at the right temperature, or frozen. Another possibility is to leave them in the garden, mulched with a foot (30 cm) of straw or hay as well as rowcover, if temperatures are below 10°F (–12°C). Our winter temperatures fluctuate a lot, so covering in-ground crops with mulch doesn’t work well for us.

Season Extension and Frost Preparations

Here’s my new Season Extension slideshow that I presented recently for the Allegheny Mountain Institute Farm at Augusta Health and the Center for Rural Culture in Goochland. Click the diagonal arrow icon to see it full screen.

https://www.slideshare.net/SustainableMarketFarming/season-extension-pam-dawling


Frosted daikon radish.
Photo Bridget Aleshire

Since Hurricane Michael passed by, temperatures have plummeted. I dusted off our Frost Alert List. First is the “Grab and Run” list of what to do. Then follows a list of factors to consider to help you forecast whether or not you are likely to get a frost. We take the night-time low temperature for our nearest town (7 miles away) and subtract 5F to predict what temperature we’ll get.

Frost Alert List
Task Crop Notes  
Harvest all edible Asparagus beans
Harvest all edible Eggplant
Harvest all edible Okra
Harvest all edible Tomatoes Incl green
Harvest all edible Peppers exposed to the sky
Harvest all edible West Indian gherkins
Harvest all edible Pickling cucumbers
Harvest all edible Corn
Harvest all edible Green bean plantings past their prime
Thick row cover Late Beans #5,6 Uncover once mild again
Thick row cover Summer squash and zucchini Spring hoops or none. Ditto
Thick row cover Slicing cucumbers Spring hoops or none. Ditto
Thick row cover Celery Double hoops -leave covered
Thick row cover Last lettuce bed Double hoops – leave covered
Set sprinklers Slicer tomatoes Overnight from before 32F till after sun shines on plants
Set sprinklers Roma paste tomatoes and peppers Ditto
Set sprinklers Other vulnerable crops Ditto
Frost is more likely on our farm if. . .
Date is after 10/14
Daytime high temperature is less than 70F (21C)
Sky is clear
Sunset temperature is less than 50F (10C)
Dewpoint forecast (Louisa minus 5) is less than 43F (6C).
Wunderground 3.30pm forecast for Louisa low temp is less than 38F (3.5C)
Little or no breeze (But see last point in list)
Soil is cool and dry
If temps are falling fast, the sky is clear, and it’s windy (esp from NW), it may be polar air moving in and we could get a hard freeze.

Savoy cabbage with frost.
Photo Lori Katz


Frost protection: fundamentals, practice and economics.
Photo FAO

If you want to understand frost  much more than you do, see

Frost Protection: Fundamentals,  Practice and Economics FAO.pdf

126 page resource on methods of frost protection, frost damage physiology, frost forecasting, passive and active protection methods, appropriate technologies, and reference material.

 

 

 


If you are pondering hoop systems for rowcover, here are our winter double hoops. The inner hoop is from 9 or 10 gauge wire, bent round a jig to make eyes. The outer hoop is 22 gauge wire and has the ends bent into hooks. We set the inner hoops every 6′ (2 m) along the bed, fit the rowcover, and roll its edges around wood stakes. then we add the outer hoops, hooking them into the ground-level eyes of the inner hoops. Lastly we tension the rowcover lengthwise. The outer hoops stop the rowcover from blowing away, and hole it in place when we push the edges up to harvest.

Double hoop system for winter rowcover.
Pam Dawling

Frosty rows of greens.
Photo Bridget Aleahire

Feeding the Soil Slideshow, Hoophouse Crop Rotations, Growing for Market Magazine

Tall sweet pepper plants in our hoophouse in early October. Photo Pam Dawling

First a photo of a couple of sweet pepper plants in our hoophouse. They are looking a bit “back-end-ish”, but are still producing fruit. We plan our rotation so that the bed which had peppers during the summer is the last to get planted to greens. This lets us get the most peppers possible. Plus, preparing the other beds keeps us fully occupied.

This week’s post is a catch up on various topics. I have been busy with speaking events (see my Events page at the tab on this site), and the busiest time of the year in the hoophouse, preparing to plant the winter greens.

On the topic of hoophouse vegetable crop rotations, I have just posted something on the Mother Earth News Organic Gardening blog. There are two lovely pairs of photos, winter and summer, demonstrating crop rotations.

Hoophouse beds in November.
Photo Ethan Hirsh


Heritage Harvest Festival

At the Heritage Harvest Festival I spoke on Feeding the Soil. Here’s my slideshow on that. Click the diagonal arrow icon to view it full screen.

Last weekend I presented Season Extension for the Allegheny Mountain Institute Farm at Augusta Health, and I will be presenting that topic again this weekend at the Center for Rural Culture, Goochland, VA 23063.

I will include that slideshow in a couple of weeks. Next week is my Alliums for October post.


I haven’t found much reading time lately, so a magazine is just the thing! I’ve finished the September Growing for Market and am just moving on to the newly published October issue.

The September issue starts with an article on profitable bouquet making (something I’ve never tried to do) by Erin Benzakein. She gives ingredients for each season, “recipes”, and systems for ergonomic working. Spencer Nietmann writes on managing seasonal farm income using a cash projection spreadsheet. If you see yourself heading for disaster, you delay buying equipment and move that expense later in your projection. Simple and effective. No bad surprises! He also advocates for using zero interest credit cards short-term to pay for an expense you are confident you can pay for before the end of the free period. His example is paying for a hoophouse until the NRCS EQIP grant money came through.

Ellen Polishuk’s Farmer-to-Farmer profile is Blue House Farm in California. Franklin Egan writes on strategies to grow organic matter levels and reduce tillage at the same time. This is to help answer the challenges of some farmers on new land that was previously in continuous industrial corn production. The farmers were growing impressive bulky cover crops in sequence, but needed intensive tillage to get those covers incorporated. This tillage knocked back the organic matter levels each time. They used a farm walk to invite other farmers to suggest improved methods to bring their land into good heart.

Sam Hitchcock Hilton wrote about an urban farm in New Orleans using events and farm meals to develop interest in their vegetable sales. It is written in the voice of the farm goat, which adds an entertaining touch.

The October issue starts with an Introduction to Korean Natural Farming, which was a new topic to me, and may well be new to most of you. The method includes indigenous microorganisms, or “bugs in a jug” (a fermentation process is used). You can learn how to try this for yourself.

Jed Beach writes about his top crops for profitable wholesaling. His hypothesis is that “there are four factors that predict which crops can be competitively profitable for small farms to grow, even at close to distributor prices.” Perishability, matching planting to sales, gross sales per square foot and gross per harvest-and-pack hour. He provides a chart of his seven most profitable seven least profitable crops assessed on these factors. Thought-provoking stuff.

Ellen Polishuk’s Farmer-to-Farmer profile this month is Sassafras Creek Farm in Maryland, with 6 acres of vegetables and 17 acres of grains. The farmers there have a clear system of employment expectations and benefits, and instructions. Half of farm sales come from a farmers market and the other half come from wholesaling to restaurants, natural food stores, caterers and other farms’ CSAs. They decided early on that running their own CSA was not for them.

I was startled by the next article: “You don’t need a high tunnel to grow ginger” from three growers in the Midwest. (“Surely you do”, I thought). They used grant money to test out growing ginger in low tunnels, some with in-ground heating coils, some with in-ground foam insulation. Soil temperature is key (60-85F). But, personally, I’d still rather have a high tunnel!

Doug Trott wrote about planning and ordering now for next year’s flower crops – useful tips for flower growers everywhere.

Lettuce slideshow, Mother Earth News Fair, FaceBook Live, Top summer blogposts, upcoming events

We drove home seven hours from the Pennsylvania Mother Earth News Fair yesterday through the rain. The remnants of Hurricane Florence. We were among the lucky people. Earlier forecasts for Florence had the hurricane raging across central Virginia.

At the Fair, I gave two workshops: Fall and Winter Hoophouses and my new Lettuce Year Round, which you can view right here. Click the diagonal arrows icon to get a full screen view.

I had a bit too much material for a one-hour time-slot, so those of you who were there and felt disappointed at what I had to leave out, you can see it here.

While I as at the Fair I did a FaceBook Live Interview about gardening in hoophouses, with another author, Deborah Niemann. Look on Facebook for Deborah Niemann-Boehle or click the topic link above. She has several books: Raising Goats Naturally, Homegrown & Handmade, and Ecothrifty.

Shade cloth on a bed of lettuce in summer.
Photo Nina Gentle

Meanwhile, Mother Earth News tells me that my post 20 Tips for Success in Germinating Seeds in Hot Weather is in third place for most popular posts this summer.

The winner  An Effective and Non-Toxic Solution for Getting Rid of Yellow Jackets’ Nests by Miriam Landman got 43,328 views in 3 months!

Weeding rowcovered spinach in winter.
Photo Wren Vile

Looking at my own website statistics, I find that for this week, the most popular posts are

  1. Winter Kill Temperatures of Winter-Hardy Vegetables 2016
  2. Soil tests and high phosphorus levels
  3. How to deal with green potatoes
  4. .Winter-Kill Temperatures of Cold-Hardy Vegetables 2018
  5. Alliums for September

For all-time, the bias is naturally on posts that have been around longest,

  1. Garlic scapes! Three weeks to bulb harvest! Is most popular, followed closely by
  2. Winter Kill Temperatures of Winter-Hardy Vegetables 2016.
  3. How to deal with green potatoes is still #3.
  4.  The Complete Twin Oaks Garden Task List Month-by-Month,
  5. Harvesting Melons
  6. Book Review, Epic Tomatoes by Craig LeHoullier
  7. Wnter Hardiness
  8. Book Review: The Lean Farm by Ben Hartman and
  9. Setting out biodegradable plastic mulch by hand

Rolling biodegradable plastic mulch by hand
Photo Wren Vile

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I’ve updated my Events page again, now that the September- April  “Events Season” has hotted up. I’ve added in a couple of new ones and updated some others. Click the Events tab to find conferences and fairs near you, and be sure to come and introduce yourself!

Ira Wallace of Southern Exposure Seed Exchange, at the Heritage Harvest Festival Tomato Tasting.
Photo courtesy of Monticello

The Heritage Harvest Festival  is September 21-22 Monticello, near Charlottesville, Virginia

I’m giving a Premium Workshop on Friday Sept 21, 3-4 pm Classroom 7. Click the link HERE to book for that.

Feeding the Soil

In this workshop I will introduce ways to grow and maintain healthy soils: how to develop a permanent crop rotation in seven steps, and why your soil will benefit from this; how to choose appropriate cover crops; how to make compost and how to benefit from using organic mulches to feed the soil. Handouts.

Book-signing Friday 4.15 – 4.45 pm.

On Saturday there are events all day from 10am to 5pm. $26 general admission.

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Saturday September 29, 2018  Allegheny Mountain Institute Farm at Augusta Health,  Fishersville, VA 22939. 9 am – noon

I’m giving a two-hour Class on Season Extension, followed by one-hour Q&A teaching tour of the hoophouse and greenhouse.

Winter-Kill Temperatures of Cold-Hardy Vegetables 2018

Here’s the long version of one of the slideshows I presented on January 13 at the Future Harvest CASA conference. Since I got home, I updated my Winter-Kill Temperatures list, which appears in the slideshow. Compared to my list for 2016, there are a few differences, nothing major. We had some extremely cold weather, as I reported last week with some sorry pictures of lettuces. Now I have some photos of the outdoor crops too. The Vates kale had mixed survival, the rowcovered Reflect and Avon spinach are damaged but OK, the Tadorna leeks are battered but hanging in there (so are we!).

Vates kale which survived temperatures of -8F and -9F outdoors, uncovered.
Photo Pam Dawling

Vates kale with a freeze-killed center January 19 2018.
Photo Pam Dawling

For several years I have been keeping records of how well our crops do in the colder season. I note each increasingly cold minimum temperature and when the various crops die of cold, to fine tune our planting for next year. We had some extremely cold temperatures of -8°F and -9°F (-22°C and -23°C) in early January 2018. We are in zone 7a, with an average annual minimum temperature of 0-5°F (-18°C to -15°C).

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, micro-climates and rain levels may lead you to use different temperatures in your crop planning.

Hoophouse Notes

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

In the hoophouse (8F warmer than outside) plants without extra rowcover can survive 14F colder than they could survive outside; 21F colder than outside with rowcover (1.25oz Typar/Xavan).

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

Lettuce hardy enough for a solar heated winter 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, 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.

35°F (2°C):  Basil.

32°F (0°C):  Bush beans, 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, chicory roots for chicons, and hearts, Chinese Napa cabbage (Blues), dill (Fernleaf), endive (Escarole more frost-hardy than Frisée), 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.

Spinach under rowcover, with our hoophouse in the background – crop protection pays!
Photo Pam Dawling

22°F (-6°C): Some arugula (some varieties are hardier), Bright Lights chard, large leaves of lettuce (protected hearts and small plants will survive colder temperatures), rhubarb stems and leaves.

20°F (-7°C): Some beets (Bulls Blood, Chioggia,), broccoli heads (maybe OK to 15F), Brussels sprouts, some cabbages (the insides may still be good even if the outer leaves are damaged), celeriac, celtuce (stem lettuce), some head lettuce, some mustards/Asian greens (Tendergreen, Tyfon Holland greens), flat leaf parsley, 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, endive, 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) if not covered, broad leaf sorrel, most covered turnips, winter cress.

12°F (-11°C): Some beets (Cylindra,), some broccoli, 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, most fall or summer varieties of leeks (Lincoln, King Richard), large tops of potato onions, covered rutabagas, Senposai leaves (the core of the plant may survive 10°F/-12°C), 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, 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), large leaves of savoyed spinach (more hardy than flat 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 savoyed 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).

Tadorna leeks, struggling but not dead, after -9F.
Photo Pam Dawling

0°F (-18°C): Chives, some collards (Blue Max, Winner), corn salad (mache), garlic, horseradish, Jerusalem artichokes, 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, Tyee). 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 die, Vates kale survives although some leaves may be too damaged to use.

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

-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

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

A cover crop of winter wheat untroubled by -9F.
Photo Pam Dawling

Year Round Vegetable Production, speaking events

Here’s my newest slide show, Year Round Vegetable Production, which I presented at the Field School in Johnstown, TN on December 7.  To view full screen, click the diagonal arrows at the bottom right, and to move to the next slide, click the triangle arrow pointing right.

The Field School is a Beginning Farmer program, under the Appalachian RC&D Council. The Field School organizes a monthly series of workshops (November 2017 through August 2018) that provides an overview of small-scale farming in East Tennessee’s mountains and valleys, taught by 20+ farmers and agricultural professionals. It is arranged by the Appalachian RC&D Council, Green Earth Connection, and many area partners with major support from USDA.

As well as my double presentation on Thursday evening, I attended a Q and A brunch on Friday morning and got the chance to meet the new (ish) farmers individually. It was a pleasure to meet such enthusiastic dedicated growers.

My other presentation on Thursday 12/7 was Crop Planning, which you can view by clicking the link.

The school session 2017-18 is already full even though they have expanded to have two tracks (Produce or Small Livestock) in this their third year. Go to their website if you are local and want to be on their waiting list if spots open up. They also sell tickets to the public for some of their workshops.

Beginning farmer training is available in most states, loosely under the USDA, but without a central organization. Do a web search for your state and “beginning farmer training” if you are looking for something like this. Or check out this list on Beginningfarmers.org.


I have been firming up several speaking events in the new year. Here some info on some of those (click the Events tab  or the individual event links for for more details):

The Chesapeake Alliance for Sustainable Agriculture Future Harvest Conference January 11-13, 2018 at College Park, MD.

Ira Wallace (Southern Exposure Seed Exchange), Gabe Brown, Michael Twitty and Craig Beyrouty are giving the meal time addresses.

On Saturday January 13 11.30am -12.30pm I’m presenting

Cold-Hardy Winter Vegetables Why farm in winter? Information includes tables of cold-hardiness; details of four ranges of cold-hardy crops; overwintering crops for spring harvests; scheduling; weather prediction and protection; hoophouse growing; and vegetable storage.

I am also participating with other speakers in a new format Lightning Session Round, 2.15-3.30pm on Saturday, where we each get 10 minutes to tell the audience the top 5 things we want them to know about a certain topic. I’m speaking on Six Steps to Using Graphs to Plan Succession Crops for Continuous Harvests

I will be signing books at the Southern Exposure Seed Exchange booth at points during the conference.


February 7-10, 2018 Pennsylvania Association for Sustainable Agriculture, Farming for the Future Conference, State College, PA https://www.pasafarming.org/events/conference.  I’ll be presenting three workshops:

Storage Vegetables for Off-Season Sales Friday 12.50 – 2.10 pm

Grow crops you can sell during the winter, while allowing yourself some down-time and reprieve from outdoor work. Choose suitable crops, schedules and storage conditions. Understand your weather and basic crop protection. This workshop will provide tables of cold-hardiness and details of four ranges of cold-hardy crops (warm and cool weather crops to harvest and store before very cold weather; crops to keep alive in the ground further into winter, then store; hardy crops to store in the ground and harvest during the winter, and overwinter crops for early spring harvests before the main season). It includes tables of storage conditions needed for different vegetables and suggestions of suitable storage methods, with and without electricity.

Cover Crops for Vegetable Growers Saturday 8.30 – 9.50 am

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

Fall and Winter Hoophouses Saturday Feb 10 12.50-2.10pm

How to grow varied and plentiful winter greens for cooking and salads; turnips, radishes and scallions. How to get continuous harvests and maximize use of this valuable space, including transplanting indoors from outdoors in the fall. The workshop includes tips to help minimize unhealthy levels of nitrates in cold weather with short days. Late winter uses can include growing bare-root transplants for planting outdoors in spring.

There will be handouts for each workshop and book signing


March 9-11 2018, Organic Growers School Spring Conference at UNC-Asheville, Asheville, NC. I’ll be presenting three workshops:

For the Gardener track: Growing Sweet Potatoes from Start to Finish

At this workshop you will learn how to grow your own sweet potato slips; plant them, grow healthy crops and harvest good yields, selecting suitable roots for growing next year’s slips. You will also learn how to cure and store roots for top quality and minimal losses. This workshop will be useful to beginners and experienced growers alike.

For the New Farmer Track: Cover Crops for Vegetable Growers

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

Sustainable Farming Practices 

An introduction to year round vegetable production; crop planning and record-keeping; feeding the soil using crop rotations, cover crops, compost making and organic mulches; production tips on direct sowing and transplanting, crop spacing, succession crop scheduling to ensure continuous harvests, efficient production strategies, season extension, dealing with pests, diseases and weeds; determining crop maturity and harvest methods.


April 12, 2018, 9am to noon,

Louisa Master Gardener Group Tour of Twin Oaks Gardens

Cold nights, Cool season hoophouse crops, CASA conference

Ginkgo Golden Puddle Day
November 10 2017.
Photo Pam Dawling

We had a few 24F nights and the ginkgo trees responded by instantly dropping all their leaves. A beautiful sight.


At the Carolina Farm Stewardship Association Sustainable Agriculture Conference I gave a presentation called Sequential Planting of Cool Season Crops in High Tunnels as part of the Friday morning High Tunnel Crop Production Intensive workshop. It’s a new workshop I prepared especially for the CFSA. I usually call the structures hoophouses rather than high tunnels, but either name is fine. It used to be said that farmers called them hoophouses and researchers and academics called them high tunnels. Nowadays there is not such a binary distinction; farmers do research and teach, researchers and academics grow crops. Here is the longer version of the slideshow, including “bonus material” I didn’t include in the 60 minute presentation. Click the diagonal arrow icon to view full screen.

On the Sunday I gave a presentation on Year-Round Hoophouse Production which was a back-to-back presentation of the Hoophouse in Spring and Summer and the Hoophouse in Fall and Winter.  You can view those slideshows by clicking the links to them on the SlideShare.net site.


I’ve added a new event to my calendar for January. You can see all the events I plan to speak at, by clicking the Events tab at the top of the screen on my home page. This one is the Chesapeake Alliance for Sustainable Agriculture Future Harvest Conference January 11-13, 2018 at College Park, MD.

On Saturday January 13 11.30am -12.30pm I’m presenting Cold-Hardy Winter Vegetables – Why farm in winter? Information includes tables of cold-hardiness; details of four ranges of cold-hardy crops; overwintering crops for spring harvests; scheduling; weather prediction and protection; hoophouse growing; and vegetable storage.

I might also be participating with other speakers in a new format Lightning Session, where we each get 10 minutes to tell the audience the top 5 things we want them to know about a certain topic. That isn’t decided yet.

I also hope to be signing books at the Southern Exposure Seed Exchange booth at some point.


Meanwhile here on the farm it’s got colder, as I said at the beginning, and even dreary some days. We are getting our winter carrots harvested, getting ready to plant garlic, adding draft-proofing strips to our hoophouse doors, and admiring and harvesting our hoophouse salad crops.

November hoophouse lettuce bed.
Photo Wren Vile

Saving watermelon seed, rainy day reading, Heritage Harvest Festival

Scooping watermelon seed.
Photo Pam Dawling

I wrote recently about saving tomato seed, and here I’ll write about extracting watermelon seed. We grow Crimson Sweet Virginia Select, which we sell to Southern Exposure Seed Exchange. I walk through the patch with a grease pencil (china marker) in July when the melons are forming and write numbers on 40 nice-looking big melons. I’m selecting for earliness, size, disease resistance and flavor.

Selected watermelon with an identifying number.
Photo Nina Gentle

Once the melons start to ripen, I go out to the plot once a week with my trusty garden cart and a collection of clean buckets, a notebook and pen, a big knife, a large slotted spoon, a couple of damp rags, a bottle of water and a big straw hat. I start testing the numbered ones for ripeness. If they are ripe I decide if they are seed-worthy, demoting any with dead vines (not disease-resistant!) or too small. I find promising replacements for any I decide not to save seed from, and number those.

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

When I have a good one, I cut it in half and scoop the heart out into a very clean bucket. I taste a piece (that’s the “good flavor” test). These days they all seem to taste good, but the first few years of seed selection, I had some I didn’t like much, so I didn’t save seed from those. See the first photo for the scooping task. Once the heart is scooped out, there is a layer of flesh with seeds in, which I scoop out into a moderately clean bucket. Then a layer of flesh without seeds for the food bucket.

Watermelon seed bucket and food bucket.
Photo Pam Dawling

In the blue bucket is my “dry zone” with my notebook. I write down which melons I harvested, any I discarded, any new ones I added, and how many are left to find in the coming weeks. Generally I harvest 7-10 watermelons per week, generating two buckets of fruit and two half-buckets of seeds. The watermelon seeds are fermented for four or five days, then washed – just like processing tomato seeds I wrote about last week.

Dried watermelon seeds in a paper bag.
Photo Pam Dawling

I harvest 5 or 6 times, from Late July to early September. I don’t want to be selecting for late-ripening melons so I stop harvesting seed long before the fruits are over.


My most recent blog post for Mother Earth News is about repairing garden hoses, most of which you already read about here. It’s in the DIY blog this time (most of my posts go in the Organic Gardening blog). I just heard some numbers for how various of my Mother Earth News blogposts this year are doing, and the big favorite topic is Growing Lettuce Year Round: Succession Planting for a Continuous Supply: 10,924 views! Growing Winter Lettuce: 4,620 views, is second favorite. people sure do love lettuce! Other popular topics this year have been Winter Hoop House Harvest Schedule, Using Open Flats (Seed Trays) to Grow Sturdy Seedlings EasilyHeat-Tolerant Eggplant Varieties, and Planting Leeks. 

How to harvest garlic scapes.
Photo Wren Vile

When I look to see which posts on this blog people visit most often, I see that garlic harvesting and garlic scapes are very popular, as are posts about sweet potatoes.


Sometimes I post links to my slideshows, but here’s a You Tube I’ve been meaning to tell you about. This is my presentation of Succession Planting for Continuous Vegetable Harvests at New Country Organics.


The September Growing for Market is out. The cover article, by Carolina Lees, advocating a Farmer Retreat. This is a wintertime regional gathering of farmers, with scheduled time for discussion and also for casual hanging-out. No imported speakers! The author is in Oregon, and envy-inducing photos of the beach-side retreat are included. But, what a good idea!

David Ross writes about grower relationships with wholesalers. Shawn Jadrnicek, author of The Bio-Integrated Farm: A Reveolutionary Permaculture-Based System . . .  writes about mulching and crimping techniques for no-till vegetables, including how to have weed-free cover crops, and get the right machinery to roll and crimp them. he uses a manure spreader to spread tree leaf mulch, and shows photos of a very tidy farm.

Rowan Steele writes about obtaining used silage tarps (as advocated by Jean-Martin Fortier) for covering beds to control weeds organically. Rowan writes about how to use the tarps and suggests coordinating a used silage tarp delivery for your small farm community. Contact Travis Quirk at the nonprofit Simply Agriculture Solutions Inc. in Saskatoon, Saskatchewan ([email protected]).  The tarps may be delivered for the cost of shipping. Canadian farmers are required to recycle their “grain bags”, but it’s hard for them to find a recycling facility in Canada, so the plastics are sent to the US. They are happy to be able to divert the material for a second use. Sounds great to me!

Jane Tanner writes about William’s WIldflowers, a floral design business run by two sisters, using lots of native flowers, especially perennials, for weddings and other formal occasions.


See you at the Heritage Harvest Festival on Friday September 8 (my premium workshop on growing sweet potatoes from start to finish) or Saturday (strolling around). Last time I looked there were still tickets available for my workshop ($20)

Heritage Harvest Festival

Asian Greens Slide Show, Crops in our Hoophouse

I’ve started my year of monthly posts about Asian greens with one about senposai and at the Mother Earth News Fair in Vermont this past weekend, I presented my slide show on Asian Greens, which is here for those who missed it. Click the diagonal arrow symbol to get the full screen version.

Today, back on the farm, I spent the morning in the hoophouse. I harvested 4 buckets of cucumbers from one 90′ bed of Spacemaster bush cucumbers. We harvested 2 buckets two days ago, and today they have really taken off!

Flowering cucumbers in our hoophouse May 25. Photo by Alexis Yamashita

I also harvested 3 gallons of green beans – we planted Strike, a very upright variety. We find that bush beans tend to sprawl in the hoophouse, and the varieties that do well for us outside (Provider and Bush Blue Lake, from Fedco Seeds), grow straggly inside and the beans curve. It’s probably because the shadecloth on the hoophouse is too dark for beans.

Strike beans in our hoophouse. See the big shade cloth over the hoophouse.
Photo Alexis Yamashita

The Gentry yellow squash are doing very well. I’ll harvest those tomorrow (we’re alternating cucumber and squash harvest days currently)

Gentry yellow squash in our hooophouse.
Photo Alexis Yamashita

The other crops in our hoophouse now are peppers (we’ve had a handful of green bells). two beds of tomatoes that have been struggling with aphids and sooty mold, and some Iron and Clay cowpeas as cover crops. See this sad picture of the aphids and sooty mold:

Tomato plant with aphids and sooty mold.
Photo Alexis Yamashita

Aphids excrete a sweet liquid called honeydew. In warm moist conditions this sugary substance grows a black mold on every deposit. This is called sooty mold. We have been dealing with it by jet-washing some of the tomatoes every sunny day, and we are winning. The photo above was specially chosen to demonstrate the problem – it’s not a crop to be proud of at this point! We use a brass jet-spray nozzle on a hose and wash them in the middle of the day, so the leaves can dry quickly – we don’t want any more fungal tomato diseases moving in!

Garlic scapes, upcoming events, hoophouse seed crops

Garlic Scapes
Photo courtesy of Small Farm Central

I always know when garlic growers in slightly warmer or more southern climates are starting to find scapes (the edible firm flower stems of hardneck garlic) because my posts about scapes suddenly become popular! My posts “Garlic scapes! Three weeks to bulb harvest,”  and “Garlic scapes to cheer us up” have been reread a lot recently, and Harvesting garlic is due for attention any time now. My Growing Great Garlic slideshow is here. Click the diagonal arrows to view it full screen.

And sure enough, our own scapes are ready too, even though this is a week earlier than usual.We harvest two or three times a week until there are no more. I love garlic scapes as one of the first outdoor crops of the spring, and a flavor different from leafy greens and stored roots, the staples of early spring.

Our tulip poplars are flowering now too, also early. Our average date for those is 5/1, and we’re a few days ahead of that. When I was a beekeeper it was important to be ready for the tulip poplar flowers, because that was our big nectar flow of the year, and I had to dash out to the beeyard and stack up 5 supers on each hive. I had to give up on the beekeeping because the combination of lifting heavy boxes and twisting was hurting my back too much. Oh, and those heavy boxes were full of thousands of stinging insects, but I didn’t mind that bit as much. The flowering of tulip poplars and the germination of ragweed are both phenology signs that signify that the Growing Degree Days have reached 200 (on a base of 50F) and that conditions are warm enough to sow sweet corn. Myself, I watch the young leaves on the white oaks and when they are the size of a squirrel’s ear, I decide it’s warm enough for corn.


This weekend I will be at the Mother Earth News Fair in Asheville, NC. Click the link to see the location, the workshop schedule and the list of vendors who’ll be there. I’m presenting two workshops, Growing Sweet Potatoes from Start to Finish on Saturday 5/6 at 12.30on the Yanmar Sustainable Agriculture Stage, followed by book-signing and chatting at the Mother Earth News Bookstore; and Succession Planting for Continuous Vegetable Harvests on Sunday 5/7 at the Heirloom Gardener Stage.

Of course, you’ll need to be there and  hear me speak to get the most out of it. I’m also doing short demonstrations of How to String Weave Tomatoes at booth 2800, New Society Publishers (near the Bookstore) on Saturday at 10 am, 11 am and 5 pm, and on Sunday at 10 am and 11 am. They’re half-hour time slots. My table top demo kit uses #2 pencils and pink tinsel.

At the New Society Publishers booth at the Pennsylvania Mother Earth News Fair, demonstrating how to string weave tomatoes.
Photo Ingrid Witvoet/New Society

The May issue of Growing for Market magazine is out, including my article about growing seed crops in hoophouses. I interviewed Clif Slade, founder of the 43560 Project at Virginia State University, about several creative sequences of food crops and seed crops he has grown in a high tunnel. (Collards, okra) as well as plant starts (sweet potatoes, onions). He farms in Surry County, Virginia.

Also in this GfM, Simon Huntley of Small Farm Central encourages small farmers to set aside two hours a week for a quick and efficient bit of online marketing “One Photo,
One Paragraph”. His goal is to help farmers stay in the spotlight with their products, without having to spend a great deal of time on it in the busy season.

Conor Crickmore has an article about preparing and laying out no-till permanent raised beds very precisely in a hoophouse. He uses the Quick Cut Greens Harvester to mow off over-size baby salad crops to clear the bed prior to broadforking and adding needed soil amendments.

Spencer Nietmann writes about what it really costs to start a farm. Jesse Frost discusses various types of plastic to cover hoophouses  (high tunnels), and lastly, Jane Tanner writes about native perennials for flower farms