Planning Winter Cover Crops

 

A cover crop mix of winter rye, hairy vetch, Austrian winter peas and crimson clover.
Photo Bridget Aleshire

If you haven’t already made a plan for winter cover crops, this is a good time to do it. Having plants growing through the winter, or at least into the winter until they get killed by cold temperatures, will improve your soil both physically (the roots hold the soil in place, preventing erosion, and they open up channels that improve the drainage) and biologically (the soil microorganisms thrive when they have active plants to cooperate with, exchanging nutrients). Cover crops will also reduce the number of weeds you have next year, because they crowd out weed seedlings. In some cases they even inhibit weed seeds from germinating.

I have some slideshows about cover crops, and am including one at the end of this post.

Choosing the “perfect” cover crops can be confusing, but any is better than none, so I encourage you to experiment and keep records, so you can improve your choices each year. It helps to know your first frost date, and your winter-hardiness zone (the lowest temperature your garden is likely to encounter). A two-week delay in sowing can seriously reduce the effectiveness of the cover crop, so follow these guidelines if you can.

A cover crop of overwintered oats the year they didn’t die.
Photo Pam Dawling

Short Simple Guide to Winter Cover Crops

  1. If the area has been fully harvested of food crops by 60-80 days before frost, sow a frost-killed cover crop or even a fast-growing food crop. Buckwheat, soy, cowpeas, spring peas, sunnhemp, Japanese millet, sorghum-sudangrass will frost-kill. Forage radish lab-lab bean or bell beans will die back and leave almost bare soil. Don’t sow a winter cover crop yet. If sown too early, oats head up in the fall and even drop seed.
  2. If the area is clear of vegetable crops by 40-60 days before frost, sow oats to winter-kill. If possible add a legume (soy and spring peas are easy, and will be killed by the frost, so they won’t complicate food crops next year). For us with a first frost date of October 14, the cut-off date for oats is September 7. This would be after growing early sweet corn, spring broccoli, cabbage, spring-planted potatoes or early season spinach, lettuce, beets, carrots. Oats will winterkill completely at 6°F (-17°C) or even milder than that, leaving the plot quick to prepare for early crops next year. So plan to put your early crops where you had oats in the winter. See the slideshow for more about oats.

    Crimson clover cover crop in flower.
    Photo McCune Porter
  3. If the area is ready for cover crops 20-40 days before frost, sow winter wheat. Add a legume such as crimson clover, if you won’t need to prepare the area before it flowers (in central Virginia 4/16-5/2, most usually around 4/20). You get the most nitrogen from the legumes if they reach the flowering stage before you kill them off in spring. If you have a legume that doesn’t reach flowering, it’s not the end of the world, you just get less nitrogen for your money. It is too late to usefully sow cover crops that are not frost-hardy, or even oats, which won’t make enough growth before getting killed.

    Cover crop of winter rye, hairy vetch and crimson clover.
    Photo Kathryn Simmons
  4. If the area is ready for cover crops up to 10 days past the frost date, sow winter wheat or winter rye and hairy vetch or Austrian winter peas. Winter rye is hardier than any other cover crop and can take later planting dates. But it is a bit harder than wheat to incorporate in the spring. Austrian winter peas can be sown later than other legumes.
  5. If you are up to 3-4 weeks past your average frost date, (we choose November 7 here, where our average first frost is October 14), sow winter rye alone. It’s too late for any legumes.

    Cover crop of winter rye still small in March, but holding the soil together.
    Photo Pam Dawling
  6. If you are later than 3-4 weeks past your average first frost date, leave the weeds or crop remains growing. It’s too late to sow a cover crop, and you’ll do more harm than good tilling up the soil. You can mow the weeds anytime you see lots of flowers and seed heads. The weed roots will hold the soil together and help feed the soil microorganisms until early spring. Be prepared to act soon in spring, so you don’t get weed seeds.
Quick Guide to Winter Cover Crops.
Pam Dawling

More Options for Each of These Time-frames

  1. 60-80 days before frost: You could follow a frost-tender cover crop with an over-wintering cover crop, for best effect. If you leave the dead tender cover crops in place, in early spring the winter weeds will start growing in the open space, so be ready for fast action. For the very earliest spring crops, forage radish lab-lab bean or bell beans will die back and leave almost bare soil. While still growing, they suppress weeds. BUT fast-maturing spring vegetables will not do well with no-till cover crops unless you add N fertilizer, as they need nitrogen more quickly than can be got from no-till.
  2. 40-60 days before frost: Austrian winter peas, crimson clover, or red clover are other options for legumes, but they won’t die when the oats do. They are relatively easy to incorporate in spring. Frost-killed cover crops can also be combined with oats. Or for a cover crop to survive the winter, sow winter barley or winter wheat with Austrian winter peas, crimson clover, hairy vetch, red clover, fava beans. Hairy vetch takes a few weeks longer than crimson clover to reach flowering. Which you choose will depend what you want to grow there next spring and when you need to plant it. After oats or other winter-killed cover crop, we like to plant our early spring food crops, peas, cabbage, broccoli, carrots, March-planted potatoes, spinach and the first sweet corn.

    Cover crop height and thickness in late April.
    Photo Kathryn Simmons
  3. 20-40 days before frost: Winter rye, or winter barley are also options for the cereal grain part of the mix, if you have those seeds on hand. In central Virginia, it’s a mistake to sow rye as early as August, as it can set seed. Austrian winter peas, or red clover are other legume options if that’s what you have. Sometimes it pays to use what you already have, as it may not give good germination if saved over to next fall. Winter rye needs 3-4 weeks after tilling in, in spring, to break down and to disarm the allelopathic compounds that stop small seeds germinating. Plan for the next food crops to be ones planted after late April, such as late corn plantings, winter squash, transplanted watermelon, tomatoes, peppers, sweet potatoes, June-planted potatoes, fall brassicas, and second plantings of summer squash, cucumbers, beans.
  4. Up to 10 days past the frost date: it’s too late for clovers. Austrian winter peas winter-kill in zone 6, but are hardy in zone 7. Hardy to 0°F (-18°C). AWP bloom in late April at Twin Oaks, before hairy vetch. Suitable crops in the year before using Austrian winter peas are the late-finishing winter squash, melons, sweet potatoes, tomatoes, peppers, middle sweet corn, June-planted potatoes. The same group of crops are suitable for following AWP, as they are planted after May 1. You can sow AWP several weeks later than clovers, but at least 35 days before first hard freeze (25°F/-4°C) – in zone 7, 8/10–10/24 (11/8 is sometimes OK)

    Winter rye headed up. Mow or turn it under very soon! Don’t let it shed seed.
    Photo Pam Dawling
  5. Up to 3-4 weeks past your average frost date: no really, it’s too late for any other cover crop. If you don’t have winter rye, don’t till! Leave the weeds, see below.
  6. Later than 3-4 weeks past your average first frost date: no, really, do not till! You could mow and tarp, to kill the weeds before spring. I’m not sure what the soil life thinks about that, though! You could mow again in early spring, or till and sow oats, if you won’t be planting a food crop in the following 8 weeks, giving the oats time to make respectable growth before turning them under.

Create a crop rotation for vegetables that includes good cover crops

If you include winter cover crops when planning a crop rotation for your vegetables, you can tweak your plan to maximize your cover crop opportunities. Here’s the steps:

 Figure out how much area is needed for each major crop (the ones needing the largest amount of space).

  1. Measure and map the space available
  2. Divide into equal plots big enough for your major crops
  3. Group compatible crops together to fill out each plot
  4. Set a good sequence, maximizing cover crop opportunities
  5. Include best possible cover crops at every opportunity
  6. Try it for one year, then make improvements

For more details, see my slideshow Crop Rotations for Vegetables and Cover Crops on SlideShare.net

Advanced Options for Winter Cover Crops

Sweet corn with undersown soybean cover crop. Photo Kathryn Simmons

Undersowing

Sometimes you can undersow the cover crop between the rows of a growing food crop, to take over after the food crop dies of frost or mowing. We do this with our last planting of sweet corn, and with fall broccoli and cabbage.

Timing is critical: Sow the cover crop late enough to minimize competition with the food crop, but early enough so it gets enough light to grow enough to endure foot traffic when the food crop is harvested. The leaf canopy of the food crop should not yet be closed. Often the best time is at the last cultivation, often about a month after planting the food crop. With vining food crops, it’s important to sow the cover crop before the vines run.

Choose vigorous food crops, but cover crops that are only moderately vigorous. Ensure the seedbed is clean and the soil crumbs small enough. Use a high seeding rate, whether broadcasting or drilling, and irrigate sufficiently.

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

No-till Winter Cover Crops

In the spring, kill the cover crop without tilling it in, and plant food crops into the dying residue. There are three ways to kill cover crops without herbicides:

  1. Winter-killed cover crops for early spring food crops
  2. Mow-killed cover crops.
  3. Roll-killing (but it usually requires special equipment).

We have had one year in 10 as a no-till year. We use no-till cover crops before Roma paste tomatoes, which are transplanted in early May. We don’t need early-ripening for these, making them a good no-till food crop. The soil under no-till cover crops stays colder than tilled soil, slowing the plant growth down.

Late-spring transplanted crops such as late tomatoes, peppers, eggplant, Halloween pumpkins, or successions of cucumbers and squash can do very well after a winter-hardy legume-grass mix no-till cover crop.

To be an effective mulch, you need to get a thick sturdy stand of cover crops, which means sowing in plenty of time, and being generous with the seed. To make the timing work, you need a previous food crop that finishes before the sowing date 4-5 weeks before the average frost (that’s September 7-14 for us).

Timing is also critical in the spring. For maximum N, the legumes in the mix will be flowering right when you need to plant the food crop. Mow the cover crop mix close to the ground, and plant right into the stubble. Transplants or big seeded crops work well. The ground will be relatively hard – you probably can’t make a furrow for small seeds).

It’s not all over with the weed-prevention after that. In our humid climate the no-till mulch biodegrades after 6-10 weeks. In July we roll hay between the rows, to top up the mulch.

Cover Crops for Vegetable Growers 2019 60 mins

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.

 

 

 

 

 

 

 

 

 

 

Ate more Eat-All Greens; Changed vegetable crop rotation

Eat-All Greens radishes on October 19. Photo Bridget Aleshire
Eat-All Greens radishes on October 19.
Photo Bridget Aleshire

Our Eat-All Greens are still alive, if not exactly thriving. The peas have been harvested to death; the kohlrabi, beets and chards are never going to amount to anything; some of the more tender Asian mustard greens are showing some frost damage.

On 12/10 we made one last crew foray to harvest – not greens, but roots! I’d noticed in the wet mild weather of late November the radishes and turnips had fattened up. We can always use a few more turnips, I thought. Plus, I was inspired by the quick-pickle radishes we’d had recently. See sustainexistence sustainable sustenance for our existence, the local foodie blog written by one of my fellow Twin Oakers. 

As we were harvesting the two and a half buckets of radishes, someone came by who said he was planning to pickle radishes, so I told him we’d keep him busy! (Actually, ten days later, there are many left to deal within the walk-in cooler.) The daikons predictably did well, as they are a fall crop. Other good varieties included Crimson Giant, which I picked up at a seed swap, and White Icicle. Sparkler (a small radish was unsurprisingly tough and woody at this overgrown stage.

We also pulled a 5-gallon bucket of delectable small turnips, including some rather pretty Mezza Lunga Bianca Colletto Viola from Seeds from Italy.

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Meanwhile we have been working on our garden planning for next year. Back in 1996 we devised a 10-plot crop rotation, which has generally served us very well for 19 years. The first few years we tweaked it a bit, but we haven’t needed major changes. You can see our pinwheel rotation plan in my book Sustainable Market Farming and in my slideshow Crop Rotations for Vegetables and Cover Crops  on SlideShare.net.

Here you can see the original card version, complete with modifications. The central card disk is fastened with one of those brass-legged paperclips and can be turned one notch each year.

Original Twin Oaks Garden Crop Rotation Pinwheel
Original Twin Oaks Garden Crop Rotation Pinwheel

The bit we want to change is the fast-turnaround where the spring potatoes are followed by the fall broccoli and cabbage. This has worked well in terms of getting high usage from our land, and freeing up one plot in ten to be Green Fallow (all-year cover crops). We did that by undersowing the fall brassicas with clover about a month after transplanting, and then letting the clovers grow for a year and a half before disking in. The difficulties with such a fast turnaround in July are

  1. If we have a wet spring, and we plant the potatoes late, we have to terminate them early (by mowing the tops) and the yield isn’t as good as it might have been. Climate change suggests we might be in for more wet springs, and with El Nino upon us, this is a good time to switch.
  2. If the weather doesn’t co-operate in July, the soil might be too wet to harvest the potatoes when we want to, and too wet to disk in preparation for the transplanting. We need to build more climate resilience into our rotation!
  3. July is stressful enough – it’s hot and humid, people are taking their turn at having a vacation.
  4. If we are late transplanting the broccoli and cabbage, the plants are oversize and don’t do well, so we get reduced yields of broccoli and cabbage that year.
  5. We prefer transplanting in the evenings in the summer (cooler for us and for the plants), and if we get late into August, the daylight is getting too short to get much done.

And so, we are seizing the opportunity to make the switch. The opportunity comes because for the last several years we have not needed to grow winter squash in the vegetable garden because it is grown elsewhere on the farm by the Twin Oaks Seeds.

Fall broccoli undersown with clover. Photo Nina Gentle
Fall broccoli undersown with clover.
Photo Nina Gentle

Our crop rotation contains several sequences of crops that we want to keep. For example, Fall brassicas/Green Fallow/early spring crop (Could be corn or potatoes, but not the spring broccoli and cabbage). Another sequence that works well for us is the Early corn/Garlic next to spring brassicas/fall carrots in one half, rye vetch and peas for no-till cover crop in the other half/paste tomatoes on the no-till the next year.

What we’ve planned for next year (a transition to our new plan) is to use the former winter squash plot for the fall brassicas/clover bit. This involves snipping that plot out of the pie and moving it after the corn #6/sweet potato and the spring potato/cantaloupe (which had morphed into 100% potatoes over the years), so that the newly housed fall brassicas can be followed by the clover year.

But that leaves potatoes only two years after other potatoes, and the late corn only two years after the middle corn, so we don’t want to do that more than once! So for 2017 onwards, we plan to insert the late corn & sweet potato/spring potato sequence after the clover, and move the early corn after the spring potatoes (when we have time to plant a winter-killed cover crop and make cultivation for the early corn easy). And switch the watermelon piece of the pie with the 3rd, 4th and 5th sweet corn successions to even out the years between corn patches.

June planted potatoes with hay mulch. Photo Twin Oaks Community
June planted potatoes with hay mulch.
Photo Twin Oaks Community

This will give potatoes, tomatoes, potatoes 3 or 4 years before the plot is nightshades again. With the corn  we get 3 years, 5 years and 2 years. Not ideal. But we don’t get much in the way of corn diseases (compared to tomato diseases) so it seems the best place to compromise.

If you get bored with holiday jigsaw puzzles and TV offerings, you could draw up your own version of our rotation, chop it up and rearrange it, and send us you suggestions. Remember to plan the winter cover crops too! Have fun!

Crop review time, harvesting potatoes, frosts and foliage

Beech tree in November foliage, Credit Ezra Freeman

Beech tree in November foliage,
Credit Ezra Freeman

We’ve had a night of 24F and two of 26F, so the season is really changing. Here’s a photo from Ezra’s blog A Year In the Woods of a beech, one of the last trees with good foliage.

In the garden we’ve been setting up the spinach beds for the winter, weeding and filling gaps. We had really good spinach germination this fall, but then the seedlings got eaten by grasshoppers or something, so we have been moving plants from where they are closely spaced to where there are gaps. Spinach is an important winter crop for us. Kale is another, and happily we finally got a good stand of that, after resowing.

We’ve also finished screening compost into our cinder block greenhouse beds. This will be our spring seedling compost and we like having it all ready to use (not frozen in a lump as it would be when we start in mid-January if we stored it outside). Over the winter we grow lettuce in the compost in the beds, and the roots and the watering help mellow the compost into a lovely condition.

Yesterday we had our annual Crop Review meeting where we gather to talk over the successes and failures of the past season and start to consider what to do differently next year. Us five Full Crew were there, along with a few of the more casual helpers and also our Food Processing Manager and our Cooks Manager. This was a horribly hard season, starting with losing a couple of key people and having a very wet spring which grew lots of weeds and got us off to a very late start. We had to cancel several crops we had planned to grow (celeriac, lots of onions, kohlrabi, peanuts) and we lost several more to weeds after we’d planted them (leeks, Chinese cabbage, winter radish, some of the turnips and beets). Unsurprisingly, we are planning on a more manageable garden next year, so we can build up our strength and be more successful with what we do grow. Plus we’ll have a substantial bank of weed seeds to cope with.

We also used the meeting time to pop garlic cloves in preparation for planting later this week. I suppose most of you would call it next week. At Twin Oaks our weeks start on Fridays and end on Thursdays, for reasons almost lost in the mists of time. Nowadays I suspect we just like the quaintness of it.

Now we are starting to harvest our second potatoes (“Irish” potatoes) which we planted in July (late, like much else this year). We bush-hogged the tops two weeks ago, so that the potato skins could thicken up and be ready to harvest before it got too, too cold. Today we will remove the hay mulch and the dried up vines and weeds, to the compost pile, and tomorrow we’ll start harvesting.

We have a Checchi and Magli SP100 potato digger, which you can see in action on YouTube. Here’s ours

Our Checchi and Magli potato digger
Our Checchi and Magli potato digger

The other main work going on in the garden is getting cover crops planted. Here are before and after photos of one plot:

Late sweet corn and sweet potatoes Credit Ezra Freeman
Late sweet corn and sweet potatoes
Credit Ezra Freeman
Late corn undersown with oats, noew mowed high, and the sweet potato patch now sown in winter wheat and crimson clover. Credit Ezra Freeman
Late corn undersown with oats, now mowed high, and the sweet potato patch now sown in winter wheat and crimson clover.
Credit Ezra Freeman

Twin Oaks October Calendar (Slowing Down)

Morris Heading Collards – our favorite
Photo credit Kathryn Simmons

Here’s our list of tasks for October. If you garden in zone 6 or 7, your list might be similar. If you live in a very different climate zone, leave a comment about your list for October, and how many weeks different your area is from ours.

During the month

Weed and thin fall crops in raised beds, especially spinach and kale. Thin carrots to 3”, kale to 12”.

Lettuce Factory: Transplant sowing #37 to fill cold frames; #38, 39, 40, 41, 42 in Greenhouse beds (9″ spacing).

Frost Alert:

Watch the forecast and if frost is expected that night

When frost threatens, harvest all peppers exposed to the sky. Corona is one of our favorite orange peppers. Photo credit Kathryn Simmons

Harvest peppers facing the sky, tomatoes, cauliflowers, corn, cowpeas, limas, eggplant, melons, cukes, okra, winter squash, Blues cabbage (hardy to 25°F), if not already done.

Double hoop and cover: lettuce, celery (hardy to 16°F with row cover).

Spring hoop and cover: squash, cucumbers.

Cover celery to extend the harvest into mid-winter. We like Ventura.
Photo credit Kathryn Simmons

Rowcover (no hoops): beans, Chinese cabbage, pak choy, Tokyo bekana, seedlings for hoophouse, collards  (hardy to 10°F, but cover keeps quality).

Cold frames:  Row cover between 32-28°F.  Add lids between 28-15°F.  Add quilts below 15°F.

Foliar spray greens with seaweed a few days before frost, to toughen them up.

Use overhead irrigation on peppers & tomatoes at night and some raised beds with tender crops.

Early Oct: Finish sowing spinach, kale by 7th for overwintering (last chance).

Transplant lettuce #37 to fill cold frames; #38, 39 in Greenhouse (9″ spacing).

Roll up drip tape from winter squash and sweet potatoes.

It’s time to roll up the drip tape from the watermelon, winter squash and sweet potato patches, in preparation for disking and sowing winter cover crops.
Photo credit Kathryn Simmons

Move stored garlic from basement to fridge – store below 40°F or above 56°F, never 40-50°F.

Mid Oct: Till finished raised beds and sow wheat or rye before the end of the month.

Garlic Beds: Compost (5-6 tractor buckets), till and prepare beds.

Transplant lettuce #40, 41, 42, 43 in Greenhouse as needed, filling any gaps.

Get soil tests done, when soil is not too wet.

5th fall disking: By mid-month disk and sow cover crops where possible. Sow wheat or rye as covercrops – too late for oats or most clovers (Austrian Winter Peas Sept 15-Oct 24).  Could sow winter wheat mid-Sept to early Nov (good for small plots that are hard to reach with the tractor) and after sweet potatoes).

Harvest peanuts mid-late Oct after a light frost.  Wash, dry, cure 6 days in solar dryer facing east (don’t heat over 85°F), store.

A well-covered sweet potato patch.
Photo credit Kathryn Simmons

Harvest sweet potatoes before soil temps go much below 55°F, or night air goes below 50°F: on 3 mild days – generally in the week that first frost usually occurs (10/7-14). Even a few hours exposed to temps below 50°F will cause chilling injury. (Frost on the leaves does not of itself damage the roots). Clip vines, dig carefully, set tubers in plant-clusters to dry on the soil. Select seed tubers (med-size tubers from high-yielding plants).  Save 100 Georgia Jet, 100 Beauregard, 20 each White and Jubilee. Cure in boxes with wood spacers and cover with newspaper, in basement with furnace going full time, for 7-10 days (85-90°F, 80-90% humidity).  Use fans. Splash water on floor. Curing is complete when skin is undamaged after rubbing two together. Restack boxes in storage cage.

Harvest white potatoes before the first frost (average Oct 14) if possible. Cure in root cellar at 60-75°F for 2 weeks, with good ventilation, then cool the cellar to lower temperatures: 50°F by 10/31, then 40°F for the winter.

Late Oct: Transplant lettuce #44, 45, 46 as filler in Greenhouse. Double hoop and cover spinach.

Planning: List successes & failures from labels. Prepare Garden Planning Schedule, Crop Review Sheets. Clean labels after info is recorded. Pray for a killing frost. File crop record info. Audit labor budget and plan endgame. Plan main garden layout. Hold Crop Review meeting.

Clear winter squash, tomatoes and peppers in order to sow cover crops, by 10/24 if possible. Sow rye alone or with crimson clover or winter peas. Crimson clover by 10/14; AWP, wheat by 11/8

6th fall disking: After the killing frost, or end of Oct if no frost: pull up tomato stakes and roll up drip tape, disk nightshades, melons, winter squash, sweet potato and white potato patches.

Check through veg in storage, squash once a week, white potatoes two weeks after harvest.

Perennials:Last mowing of clover in grapes in early Oct, not too short, and not too late in the year. Weed & mulch strawberry beds, and remove extra runners. Renovate if not already done. Start weeding, fertilizing and mulching the blueberries, raspberries, rhubarb and grapes.

Time to say goodbye to the rhubarb until April.
Photo credit Kathryn Simmons

October Harvests: Asparagus beans, beans, beets and beet greens, broccoli, cabbage, cantaloupes, carrots, cauliflower, celeriac, celery, chard, Chinese cabbage, collards, corn, cow peas, cukes, edamame, eggplant, horseradish, hot peppers, kohlrabi, komatsuna, leeks, lettuce, limas, maruba santoh, okra, pak choy, peppers, radishes, Roma paste tomatoes, scallions, senposai, spinach, tatsoi, tokyo bekana, tomatoes, turnips and turnip greens, winter radishes, winter squash, yukina savoy, zucchini.  Could lightly harvest rhubarb before frost.