Alliums for September: plant potato onions, sow ramps, eat Welsh onions, move stored garlic

Potato onion plant with young shoots.
Photo by Kathryn Simmons

Alliums to Plant in September

Divide and replant Egyptian onions and perennial leeks

Divide and replant perennial alliums in September (August-October) to increase the size of the patch and get more next year.

Plant large potato onions (2-2½”, 5-6 cm)

  • It’s better not to try to store very large potato onions over 2½” (6cm) for planting, just eat them (they sprout easily).
  • All large potato onions store poorly, so keep planting stock in the refrigerator until planting in late September or early October. Jeff McCormack does not recommend planting before September.
  • For 360′ (110m) @ 8″ (20cm) you need 540 bulbs plus 30%-40% spare. Approximately 760 bulbs. 150 large bulbs weigh about 25# (11kg)
  • Plant them at 8″ (20cm). If there are not enough large onions available, increase spacing or fill out with medium onions.
  • Cover with ½-1″ (1-2cm) soil, and add 4″-8″ (10-20cm) mulch.
  • Refrigerate any leftovers for November planting with the medium-sized onions, or eat or sell now.
  • Yields can be 3 to 8 times the weight of the seed stock, depending on growing conditions.
  • Individual bulbs can be grown indoors in a pot to produce a steady supply of green onions during the winter.

Sow ramp seeds in woodlands

Mature harvested ramp plants.
Photo Small Farm Central

In zones 3-7, sow ramps seed during August and September (see August blogpost)

Ramps (also known as Wood Leeks or Wild Leeks) are a native woodland perennial, and can be found throughout the eastern-half of the United States, as far west as Oklahoma and as far north as the central and eastern provinces of Canada.

Ramps, (Allium tricoccum) have some of the flavor components of leeks, onions, and garlic. There are projects to re-establish ramps in a number of regions in the Eastern United States.  Carriage House Farm is one such attempt by Grow Appalachia, which is a program of Berea College in Kentucky, Grow Appalachia works with farmers, gardeners, ranchers, and conservationists across a five state area to reintroduce old native and heirloom species of plants.  Ramps is/was one plant in this program. It takes two years for ramp seeds to germinate and another 2-3 years till they hit harvestable levels.

Having Your Ramps and Eating Them Too is a book by Glen Facemire

Alliums to harvest in September

Harvest Egyptian walking onions (topset onions, tree onions) for pickling, leaves of Egyptian onions and perennial leeks (September-April for cutting those)

Egyptian onions produce tiny red-purple bulbs in the umbel instead of flowers, and were previously named Allium cepa var. proliferum. According to Wikipedia, they are now known to be a hybrid of A. cepa and A. fistulosum.

Japanese bunching onion and Welsh onion (native to China, not Wales) are Allium fistulosum. They are sometimes used as scallions, as are some A. cepa bulbing onions. Young plants of A. fistulosum and A. cepa look very similar, but may be distinguished by their leaves, which are circular in cross-section in A. fistulosum rather than flattened on one side.  A. fistulosum has hollow leaves (fistulosum means “hollow”), scapes and does not develop bulbs – the leaves are the part that is eaten. Welsh onions are also known as cibol, chibbles (in Cornwall), escallion (in Jamaica), negi (in Japan), pa (in Korea), as well as green onions, salad onions, spring onions,. These general last names are also used for other kinds of onions where the leaves are the part eaten.

Perennial leeks are Allium Ampeloprasum. Common leeks are Allium ampeloprasum var. porrum (more about leeks in October and March). Elephant garlic is botanically a leek (A. ampeloprasum var. ampeloprasum).

Other Allium Tasks for September

See Alliums for August for more on all of the following jobs which continue into September:

  • Snipping and sorting garlic and potato onions
  • Trimming, sorting and storing bulb onions
  • Eating onions and garlic from storage
  • Inspect onions and garlic at least once a month. Remove bulbs which are sprouting or rotting or else the whole batch may spoil.
  • At the end of September I make the decision about how many potato onions to keep back for planting (see August for our calculations).
  • We also move garlic from warm storage to cool storage (more info below)

Potato onions store very well through the winter so long as they are well-cured, dry, well-ventilated, and not packed over 4″ deep. Ideal conditions are a temperature between either 32–41°F (0–5°C) or 50–70°F (10–21°C) with 60-70% humidity.

Polish White – our softneck garlic variety.
Credit Southern Exposure Seed Exchange

Special Allium Topic for September: Garlic Storage

Before trimming your garlic, I hope you were sure it was fully cured, and you set aside any non-storing bulbs, such as those with damaged cloves, or any over-mature, springing-open bulbs. It usually works to select your seed-stock bulbs at the same time.

Commercially, garlic is stored in the dark at about 32°F (0°C) and 65% humidity, and depending on the species and variety, it may keep six months or more. I have heard that garlic can be stored for up to nine months at 27°F (-2.7°C), but I have not tried that myself. It does not freeze until 21°F (-6°C). Do not store peeled garlic in oil, as garlic is low in acidity and the botulin toxin could grow.

For storage, garlic (like onions) does best with a humidity of 60%–70%. Refrigerators are usually more humid than ideal.

Garlic will sprout if kept in a temperature range of 40–56°F (4.4–13°C), or if it is allowed to get cold then warm. So long as temperatures remain over 56°F (13°C) you can store garlic almost anywhere. You can use an unheated room in your house, a root cellar, garage, etc. Maintain good air circulation. Most varieties store reasona­bly well in a cool room if hung from the ceiling in mesh bags, or spread on shelves in a layer less than 4″ deep.

In our climate, with a long period in the danger zone temperatures of 40–56°F (4.4–13°C), we keep alliums in the warmer storage range (60-70°F (15.5-21°C) or hotter) in a basement until late September or sometime in October when ambient temperatures in the basement drop close to 56ºF (13°C). We then move our eating garlic from the basement to the walk-in refrigerated cooler at 32–41°F (0–5°C), 95–100%. The low shelves in the cooler near the compressor are damper and do not work well. We use the high and dry shelves.

Juggling space for various crops, moving the garlic out of the basement makes space available for the winter squash harvests in September and October. By this time most of the apples from the walk-in cooler have been eaten, and space is available there. Also there is no longer the problem of ethylene emitted by the apples, which causes garlic to sprout. Ideally ripe fruits and garlic would never be in the same storage space.

Softneck garlics store longest. Silverskins store up to 12 months under the best conditions. Most hardnecks last 4-6 months but Music and Chesnok Red can keep 7 months or more here in central Virginia.

Storage of Seed Garlic

We store our seed garlic on a high shelf in the garden shed, at quite variable ambient temperatures, where it does fine until late October or early November when we plant it. Seed garlic does not require long-term storage conditions! The ideal storage conditions for seed garlic are 50-65°F (10-18°C) and 65-70% relative humidity. Storing in a refrigerator is not a good option for seed garlic, as prolonged cool storage results in “witches-brooming” (strange growth shapes), and early maturity (along with lower yields). Storage above 65°F (18°C) results in delayed sprouting and late maturity.

Siberian garlic.
Photo by Southern Exposure Seed Exchange

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.

Twin Oaks September Garden Calendar

Welcome to Twin Oaks!
Photo by Bridget Aleshire

THE SECOND SPRING

Here’s our Garden Task List for September: 

During the month

Weed and thin carrots and brassicas (kale to 12”).

Lettuce Factory: Sow hardy lettuce every 2 days till 21st, (3 rows/planting) then every 3 days. Sow #34-46 this month. Transplant 120 every 3-5 days (1/3 bed) #27, 28, 29, 30, 31, 32, 33 for last outdoor planting (Dec harvest). Transplant  #34, 35, 36  9/24-9/30 for frames

Root cellar: air and cool to 60°F by mid-September

Collect seed from Roma tomatoes if necessary.

Screen compost and fill old greenhouse beds before October, for winter lettuce and spring seed compost.

Early Sept: Prepare and plant new strawberry beds if not done in late August, using rooted potted runners or plants carefully thinned from last year’s beds (see August for details).

Transplant collards and kale if necessary. Transplant lettuce #27, 28, 29, 30.

Retrieve spinach and onion seeds from the freezer. After acclimating spinach seeds, sprout 4oz/bed (1 cup/10,000 seeds) for spinach #1 in fridge for one week, then direct sow (if <68°F, and dead nettle has germinated). If still hot, sow (preferably pre-sprouted) spinach in Speedling flats in float tank. 9/20 is last sowing date for fall harvesting. [Could broadcast oats into spinach at planting time for weed control & cold weather protection.]

Sow if not done already: kale and collards by 9/15; turnips by 9/30; radishes, kohlrabi, daikon and other winter radish, miscellaneous fall greens, scallions.

Plant large potato onions this month or early in October, at 8” (wider if supply limited). Cover with ½-1” soil, mulch with hay.

2nd fall disking: Watermelon plot when 800 have been harvested. Roll up drip tape first, or move to new strawberries.

Mid Sept: 7-14 Sept is the best time to sow vetch & rye, 1:2, 2# of mix/1000 sq ft (75#/acre) on old spring broccoli patch; crimson clover and rye, 1:2, at 55#/acre.

Transplant lettuce #31, 32.

Sow 1st sowing of hoophouse seedlings (hoop and cover).

Bring 6 tractor buckets compost to hoophouse for fertilizing fall and winter crops.

Move stored onions from basement to fridge, after apples peak in mid-September, and space available.

3rd fall disking: corn #3, #4, #5. Part of corn #3 plot may be used for new strawberry beds.

Late Sept: Sow spinach #2 for spring harvesting (9/20-9/30), and 2nd sowing of hoophouse seedlings and cover.

Transplant kale for spring, filling gaps; lettuce #33, finishing up the last outdoor bed; [#34, 35 & 36 in cold frames?] Plant large potato onions (>2”) if not done earlier.

Move garlic from basement to fridge late September-late Oct as needed to make room for winter squash.

Weeding: this is a good catch up time on weeding in the raised beds.

4th fall disking and seeding: Sow cover crops wherever possible (in unused raised beds too). The last chance for oats is early Sept (9/15??). Can sow winter wheat (winter-killed in zone 4) or winter barley (dies in zone 6) if oat planting date missed. (Oats winter-kill in zone 8). Can sow hardy Austrian winter peas in late Sept at 8oz/100sq.ft. with rye. Can sow red clover this month.

Bush-hog late corn if undersown with oats and soy cover crop.

Perennials: New strawberry beds: Prepare and plant by mid-September if not done in late August. Weed strawberries. Could till up grass in grape alley & sow clover if not done in March. If clover sown earlier, let it seed.

Harvest and store winter squash: Acorn (pepo) types (stem still green, ground spot “earthy” or orange), store 1-4 months; Maximas: Cha Cha, Jarrahdale, Kabocha (stem 75% corky) store 3-5 months; Moschatas: Butternuts, Cheese (peanut colored skin, no mottling or streaks) store 4-8 months, or more. Leave on live vines as long as possible, avoiding frost on fruits. Cut leaving long stem using pruners; handle gently.

September Harvests: Asian melons, asparagus beans, beans, beets and beet greens, broccoli, cabbage, cantaloupes, carrots, cauliflower, celery, chard, Chinese cabbage, corn, cow peas, cukes, edamame, eggplant, horseradish,leeks, lettuce, limas, maruba santoh, okra, pak choy, peppers, hot peppers,radishes, Romas, scallions, senposai, summer squash, Tokyo bekana, tomatoes, turnips, watermelons, winter squash, yukina savoy, zucchini.  It is possible to lightly harvest rhubarb during September, if wanted.