Alliums for April: transplant scallions, grow onion sets, eat garlic scallions

Young cucumber plant in a hoophouse bed of scallions in April.
Photo Pam Dawling

Allium Planting in April

  • Divide and replant Egyptian onions and perennial leeks, during March or April
  • Transplant more scallions (These will be our second outdoor ones)
  • Sow seed for onion sets 4/1 (See Special Allium Topic for April below)

Allium Harvests in April

  • Trimmed scallions from our hoophouse in late March.
    Photo Pam Dawling

    Harvest hoophouse scallions 3/18-5/20 (our third sowing)

  • Cut leaves of Egyptian onions & perennial leeks, Sept-Apr
  • Dig garlic scallions (see Alliums for March)
  • Harvest ramps, sustainably for one month, from when tree buds appear (late March or early April in the Appalachians).

Alliums to Eat from Storage in April

  • Eat softneck garlic from storage once all the hardneck has been used (softneck stores longer)
  • Eat bulb onions from storage, including bulbils from Egyptian onions if you stored those.

Alliums to Weed in April

Softneck garlic beds in May.
Photo Bridget Aleshire

April is weed season! All overwintered alliums will need weeding once a month from March, until harvest. See Alliums in March

Special Allium Topic for April: Growing Onion Sets

Onion sets are commonly sold in feed stores loose by the pound, and many people know of no other way of growing onions. But sets don’t grow the best onions (unless growing from seed is impossible for you). Sets are dried down small onions (which come out of dormancy when replanted the next spring), not to be confused with perennial multiplier onions such as potato onions.

William Shoemaker, former senior research specialist in agriculture at the University of Illinois, wrote about growing onion sets in 2010:

“Sets won’t make the high quality bulbs that the plants will because they are older, biennial plants that have shifted into the reproductive stage. . . .  But they could be useful for growing bunching bulb onions early in plastic. I’m not sure that’s the best use of plastic though. I think large fresh bulbs from plants would be better.”

“We have one of the oldest onion set industries in the country in northern Illinois, near Kankakee. Over time I’ve learned how they do it. Kind of strange but it makes sense once you understand how they do it.”

“First, you are trying to create very small bulbs. The smaller, the better. Let me explain. When you buy onion sets, you often see most of them are about 1/2″ in diameter. Those are best used as green onions because they are big enough to bolt. So plant them very close together and plan on harvesting them early as your first green onions (scallions). Those that are 1/4″ or smaller in diameter will be much less likely to bolt and will grow into small, early dry bulbs. They’re less physiologically advanced! They won’t get to be huge, so don’t count on them for that. Instead, use them for early bulbs, even bunched green bulbs. They’re very good for that purpose. So onion sets have a much different Best Use than onion plants.

Remember, onions are biennials. They want to flower after overwintering. So large onion sets will always flower. You can break off the flower stems, but don’t count on big bulbs. Small onion sets can bulb reliably but will not make really big bulbs, certainly not like direct-seeded onions or onion plants. Each approach is valid, but has a different purpose in the end. And . . . they are daylight sensitive, so make sure you pick the right variety for your area of the country. In the north you want varieties that are long daylength (short nights. They will begin to bulb when nights get short). In the north, that’s in June (so plant early!).

If you are growing in the south, plant short daylength varieties (Granex types are an example). They will begin to bulb during longer nights, earlier in the Spring. But you will plant much earlier in the year so the plants can get well-established and grow big shoots to feed the bulbs as they grow.

Okay, back to growing sets (which CAN be used to grow seed). To grow the sets the year before growing them out for seed, plant seed early in the season (April Fool’s Day in Chicago. No kidding, No coincidence). Plant them in shallow furrows REALLY THICK. I mean 12-24 seeds per inch of furrow. The reason is you are essentially letting them get started, but not letting them thrive. Grow them out very thickly and they will stay very small. They will eventually form small bulbs because they will grow normally but under intense competition. As hot-dry days occur in July and August, they will go into dormancy.

Dislodge them from their roots after tops dry down. You can just use your hand to shove them aside and they will dry down nicely in place. Put them in trays and put them somewhere they can finish drying. Be sure to pick up the smallest ones. They will grow into nice onions next spring. Remove debris and excess dirt. Once they’ve dried down, they can be cleaned up by brushing off the loose layers of skin and bagging them in something well-aerated. Netted bags or nylon hose works fine. Store them somewhere very cool (35F) and dry till planting time next Spring. Separate them for their distinct uses and plant accordingly.

That’s the kernel of the idea behind growing onion sets. There’s more to be said but not enough time/space here. But this should give you the basics and enough for success.

One other pointer. If you have a variety you really like and want to make lots of sets, look at bulk onion seed prices. It’s amazing how much cheaper they are per unit when you buy in bulk. If you can buy with others and buy bigger quantities, you can save money.”

A grower in Texas, about 125 miles from the Gulf, responded that they used the word “sets” to refer to small live onion plants, such as you might buy online by mail order.

“The sets look like onions that have been started, allowed to grow to 1/4 inch diameter at the biggest. The tops are cut off with a couple of inches of green, then bundled and sold.  When I asked, I was told they were started in a climate controlled greenhouse mid-summer.”

That grower had found a way to resolve their problem of onions that were too big.  If they planted their “sets” out in October or November, they got huge onions from them.  Since their customers were not fond of really big onions, the grower kept their young plants (“sets”) in the fridge until January/February, then planted out.  Harvest was the beginning of June.

A fine bed of onions in spring.
Photo Kathryn Simmons

This is the last of the year’s posts on Alliums for the Month. In May I will start a series on cooking greens for the month.

You can read the other allium posts here: