Alliums for August: plant perennial leeks, eat onion greens, sort potato onions again, move bulb onions into cooler storage

 

Perennial leeks.
Photo by Southern Exposure Seed Exchange

Plant perennial leeks (Oepri, Perlzwiebel)

These will be dry bulbs at this point of the year and can be re-spaced between August and October into a larger planting for next year.

August onion harvests

In cooler climates (if the quality is still good) the tops/greens/leaves of Egyptian onions and perennial leeks can be cut and used fresh. The larger bulbils of Egyptian onions and perennial leeks can be used in mixed pickles. Garlic and bulb onions can be eaten from storage.

Egyptian walking onions.
Photo by Southern Exposure Seed Exchange

Sort potato onions twice in August

Early August: at the third sorting of the potato onions, I separate the clusters, trim the tops and sort by size. Sorting by size is not essential, but I do it to help me figure out what to save for planting and what to eat or use as seed (for planting). We sort smalls (<1.5”), larges (1.5-2.0”) and eaters (>2.0”). And compost material. The rack space required after this stage is only a third of what it was before that.

At the end of August I sort through again, and make initial plans about what to do with surplus planting stock (sell, give to friends). At the end of September I make the decision about how much to keep back for planting. I used to put the onions into net bags for storage, but I found I get better results if I just leave them in a single layer on the racks. The small ones stay there till late January, through freezing conditions (or more accurately, alternating freezing and thawing conditions). They can appear to be frozen solid, but are in fine condition. Ideal conditions are 32-40F, 60-70% humidity, with good ventilation. Layers should not be more than 4” deep.

Yellow potato onions.
Photo by Southern Exposure Seed Exchange

Save seed-stock potato onions

Seed saving is a natural part of growing potato onions. We started in 2000 with 0.5 pound of seed stock, planted late in the spring. We harvested only 1.5#, but we continued, adding in more seed-stock, and planted 46# for 2003, (90’ large, 180’ small). At that point I was dividing into 3 planting sizes: small (<1”, 30-60 bulbs/pound); medium (1-1.5”, 16-22 bulbs/pound); and larges (>1.5”, 7-8 bulbs/pound). For 2004, I planned to plant large:small in a 1:2 ratio by area, to get enough small and medium onions to plant the same area the next year, and to get lots to eat as well. But the 2003 harvest had a high amount of large onions, and I decided to plant them all, increasing to 540’. We expanded to plant 720’, in a large:small ratio of 1:3 by area (i.e. 180’ large, 540’ small). This gives us enough smalls to plant for the next year, and plenty of larges and eaters. Someone growing for maximum seed-stock would probably want to plant a higher ratio of large ones, in order to get more smalls.

Instead of weighing all the onions, I now know I need to save 3 racks (probably 65#, 450 bulbs) of larges (1.5-2.0”) and 5 racks (probably 75#, 2100 bulbs) of smalls (<1.5”) for planting next year’s crop. This allows a margin for decay. The small ones really are very stable, it’s the larger ones that are more prone to sprouting, so I pull those out whenever I pass by.

Australian Brown storage onion.
Photo by Southern Exposure Seed Exchange

Move bulb onions into cooler storage

  • In July I mentioned that bulb onions can safely be stored at 60°F-90°F (16°C-32°C) if they have not been refrigerated at all. This applies only to fully cured onions with dry necks. (Green onions need refrigeration at 32°F-41°F (0-5°C), 95-100% humidity.)
  • For cured dormant onions it is very important to avoid the 45°F-55°F (7°C-13°C) range, because that’s when they sprout.
  • For storage, onions and garlic do best with a humidity of 60%-70%. Refrigerators are usually more humid than ideal. If you have a barn with the right temperatures, that will work better for long-term storage.
  • In our climate, with a long period in the danger zone temperatures, we keep alliums in the warmer storage range in a barn, shed or basement until ambient temperatures drop close to 55ºF, and then move them to a refrigerated cooler at 32°F -41°F (0-5°C) 95-100% humidity.
  • Do not freeze: onions get chill injury at 31°F (-0.5°C)
  • If at all possible, do not store onions with fruits, including squash, as these exude ethylene which promotes sprouting.

More reading

Other southern onion growers might like to read this publication by Dr Joe Masabni of Texas AgriLife Extension, called simply Onion

Walla Walla large non-storage onion.
photo by Southern Exposure Seed Exchange

Collect ramp seeds

If you have been wild-crafting ramps (more on that in March), this is time to pay the piper. Collect seed and scatter it over the patches you dug from. Or collect seed to grow in woodlands at home – without of course, taking too many away from a place they could grow naturally. See the article in Modern Farmer. The seeds scattered in zones 3-7 in early fall, take 6 to 18 months to germinate, and the plants take 5-7 years to grow to harvestable size. Thus it’s easy to see how wild ramps have been seriously over-harvested.

Buy seeds year-round and bulblets in late winter at rampfarm.com and mountaingardensherbs.com.

Read more in Growing and Marketing Ginseng, Goldenseal and Other Woodland Medicinals by W. Scott Person and Jeanine Davis of North Carolina.

Alliums for July: harvest minor alliums, finish harvesting bulb onions, snip and sort garlic and bulb onions.

Siberian garlic.
Photo by Southern Exposure Seed Exchange

Allium planting in July

In Virginia, July is not a big month for planting alliums. If you have perennial leeks or Egyptian onions you could if necessary divide clumps and replant them. But I would postpone doing this if I could and replant dry bulbs in August, or divide newly re-sprouting clumps in September.

Allium harvesting in July

In June I listed dates of our usual allium harvests for that month. Some of the minor allium crops (shallots, leaves of perennial alliums) can be harvested in July, but some, like the tiny, purple shallot-like L’itoi perennial onion (Allium cepa var. aggregatum ) die back in June and are sending up new green shoots by early July, so you’ll have to wait for those to be big enough to harvest. During dormancy you could divide the clumps and replant. Harvests of full-sized bulb onions and cipollini (small bulb onions) continue through July.

Bulb onions

I discovered our bulb onion (A. cepa var. cepa) harvest dates had ranged more widely than the 6/15-6/30 I reported last month. In the years 2008-2012, we harvested bulb onions 6/4–7/26, depending on the variety and the weather. In October I’ll write more about choosing onion varieties for your area.

Bulb onions curing on a rack.
Photo Wren Vile

Curing bulb onions

Some books recommend curing in the outdoor sun. These books are written further north or further south! This doesn’t work in our climate, where we need to provide partial shade, moderate temperatures, and good air flow (and no rain). Further north, temperatures are lower, and onions do not bake during outdoor curing. Further south (in Georgia for instance) onions mature much earlier in the year (they have been growing over the winter). The sun is not yet too intense or the humidity too high, and they can cure onions in the field there.

Handle onions gently – many rots are the result of poor handling post-harvest. Spread in a single layer in a warm dry place, and check every few days. The ideal conditions are 85ºF-90ºF (27ºC-32ºC) with constant air movement, no direct strong sunlight. We use racks in a barn, with fans to keep the air moving.

Trimming, sorting & storing bulb onions

Trimming should begin about two weeks after you hung the onions to cure. Test them by feeling maybe a dozen necks to see if they are ready. Pinch the necks gently just above the bulb, and then rub your thumb and forefinger together. They are ready for trimming if the majority of the necks feel dry and papery. The necks should not feel slippery or moist. If more than one or two still feel damp, but not slippery, wait a couple of days before testing again. Do not wait more than three weeks after harvest to get the onions in storage. The longer you leave the onions hanging, the more rot you will have to deal with.

To trim get a good pair of scissors, and a glove on your scissor hand to prevent blisters. Trim the necks off about ½” (1 cm) from the bulb, and trim all the roots off.

When trimming, sort the onions into three categories. Onions with wet necks or soft spots are for immediate use at home. Bulbs that feel firm and have dry necks are storage bulbs, and should be trimmed and put into mesh bags, which we store lying flat on shelves in our basement. Most onions store reasona­bly well if spread in a layer less than 4″ deep or hung from the ceiling in small mesh bags. Avoid large bags where the weight of the onions will crush the ones at the bottom. Ensure good air circulation.

The third category is for bulbs that aren’t obviously use first, but for some reason might not store for months. Maybe the necks have a spongy feeling, or the skin is split, or the necks slip a little bit. Label these onions “Use Soon,” trim them into mesh bags and put them in the basement like the storage onions.

Onions can be stored at 60ºF-90°F (16ºC-32°C) if they have never been refrigerated. It is important to avoid the 45ºF-55°F (7ºC-13°C) range, because that’s when they sprout. We have limited refrigerated storage, so we keep alliums in the warmer storage range until room temperatures drop into the danger zone, by which time there is space in the cooler. More about onion storage in August.

Onion harvest
Photo by Raddysh Acorn

Here’s information from the Roxbury Farm Harvest Manual (upstate New York) – a quite different story from Virginia:

Storage onions

Pull the onions out of the ground, clean off some damaged leaf parts, taking care not to remove too many of the outer layers. Cut off the tops immediately, 2-4″ (5-10 cm) above the crown.  If for long-term storage, bring the onions to the greenhouse for curing. Cover the greenhouse with 80% shade cloth to protect onions from sunscald.

As soon as the necks are sufficiently dried up (you can no longer roll any stems between your fingers and the stem tissue feels like paper), and the leaves easily crumble off, give them a superficial cleaning, and move the onions into the barn (and not in the cooler due to high moisture levels). Store at 32ºF-41°F (0-5°C) 65-70% humidity.

Green bulb onions, harvest and cleaning

Pull the 3-4″ diameter onions out, before any leaves die, by grabbing the plants as low as possible on the stem to avoid crushing the green stems. Place the onions on the top of the bed all facing the same way. Clean off the outer leaves around the bulb to leave a clean white bulb. Bunch 2-4 onions together with twisties. Cut the excess length off the leaves so the bunch fits lengthwise in the box. Pick up the finished bunches, and place them in the box.

Washing onions would shorten their storage life. Remove most of the dirt in the field. Bunched fresh onions look much nicer when clean. Spray off the onions with a hose but do not dump them into a washing tub. Pack in closed containers for storage longer than a week. Store at 32-41°F (0-5°C), 95-100% humidity.

———————————————————————————————————–

Harvest minor alliums

Cipollini (A. cepa var. cepa) will be ready to harvest from spring transplants here in the first half of July, if they weren’t ready in late June. We sow those in plug flats 1/25 and transplant 3/21. Read more about cipollini in the June post. We love Red Marble, which stores really well. Purplette disappointed us – it doesn’t store well.

French Red shallots.
Photo Raddysh Acorn

Shallots (A. cepa var. aggregatum) grown from seed started in late January and transplanted in March will mature here 7/4 -7/30, 4-8 weeks later than those grown from replanted bulbs (planted in October). We started with a packet of seeds, replanting all we grew for several years. We got lots of winter-kill trying to over-winter the bulbs in the ground. To save bulbs for replanting in early spring, refrigerate them. And accept a later harvest than the 6/10 of fall-planted bulbs.

Top-setting onions (aka Egyptian onions, tree onions, walking onions) produce tiny red-purple bulbs in the umbel instead of flowers, maturing in September. They were previously named Allium cepa var. proliferum. According to Wikipedia, they are now known to be a hybrid of A. cepa and A. fistulosum. The larger bulbils can be harvested in July, and used to make mixed pickles.

—————————————————————————————————————–

Other Allium tasks for July

Trimming garlic stems (blue nail polish optional!).
Photo by Brittany Lewis

Snipping, Sorting and Storing Garlic – see the link to my previous blogpost, where I spelled out these tasks, including setting up, snipping and sorting into three categories for replanting, for storing and for using soon. Garlic can be stored in the same high temperature range as bulb onions, provided it has never dropped into the sprouting temperature range of 40-55°F (5-13°C)

Sort potato onions – see the first step of this process described in my June post and the harvesting described in my May post. We made slatted racks 5′ by 2.5′ (150 x 75 cm) which stack on each other leaving space for air. Curing is important for quality and long-term storage. Space the bulbs loosely on the racks to provide good air circulation. If humidity is high, use fans, dehumidifiers or an air conditioned room, to improve drying. Curing takes 2 to 4 weeks.

I aim to sort through our potato onions once a month, starting a few weeks after harvest.

7/10-7/15: This could be the second sorting for fall-planted potato onions, the first sorting for late winter planted ones. Keep the clusters together, as breaking them apart stimulates sprouting. Wait till the third sorting, in early August, to snip off tops, separate the clusters, sort by size and decide how many to save for replanting. I’ll tell you about that next month.

Remove any rotting onions for immediate use or composting. Start sorting with the largest ones, in case you run out of time. Remove all that are bigger than 2″ (5 cm), bag, weigh, record and label. If you are on a fast track to increase your crop, refrigerate all the large onions at this time, carefully labeled so they don’t get eaten, to plant in September. Refrigerate or plant them, or eat them, the large ones won’t keep long.

Potato onions in early spring, after they have divided into a cluster.
Photo by Kathryn Simmons