University of Vermont Extension 
Department of Plant and Soil Science

 Spring News Article

Dr. Leonard Perry, Extension Professor
University of Vermont
If you like to eat and cook with onions and garlic, and aren’t familiar with their close relatives, you should try shallots and scallions.  They’re easy to grow, and particularly with shallots you can save money by having some in your garden to harvest.
Although many just harvest regular onions early before they form bulbs, and call these “green onions” scallions, the true ones are specialized onions whose bulb at the base is about the same size as the base of the leaves.  You may see these referred to as “bunching” or “non-bulbing” onions.  Chop and use these in soups, stews, salads, and as a garnish for a mild onion flavor.
Scallions need a well-drained soil, and somewhat even moisture.  But since these don’t grow as vigorous, long, or as big as onions, they need less fertility.  A soil amended with compost and well-rotted manure, and perhaps some organic fertilizer (according to label rates) during soil preparation, should suffice.  Make sure the site is in full sun, as shade can greatly slow growth.
You can sow scallion seeds in early spring to harvest in summer, then again in late summer to harvest in fall or early winter.  In a protected spot, and with deep straw mulch, you might even get them to survive over winter.  Sow seeds one-half inch or less apart, in rows that are an inch apart, then thin later to about two inches apart.  About 500 seeds will sow about 10 feet of row. Or, you can sow at this spacing in bands that are 3-inches wide. 
Since they don’t compete well with weeds, use a site that is free of weeds and weed seeds if possible.  Keep them weeded often while weeds are small, to avoid damaging the shallow scallion roots.  Plant or sow in a part of the garden that hasn’t had onions or their relatives for a couple of years.  This “crop rotation” will help with soil fertility and reduce pest pressure.
As plants grow, hill up some soil around them to increase the blanched white portion at the base.  Or, if you start seedlings indoors to transplant out in spring, plant deeper than you would other seedlings, and an inch or two apart.  To sow indoors, sow 8 to 10 weeks before the last frost date as seeds are slow to germinate.
You can harvest scallions when they reach 6 inches tall.  The more they grow, the stronger the taste.  Harvest by gently pulling, or loosening the soil underneath with a spading fork.  Trim roots off and any dead or damaged leaves, wash, and store in the refrigerator.  They should last a week, or longer if you wrap them in moist paper towels in a plastic bag.
If you want to try and have scallions last over winter, try ‘Evergreen Hardy White’. You can then divide the clumps the second summer to start a new crop.  ‘Nabechan’ is a traditional Japanese cultivar (cultivated variety) which has thick lower stems or “shafts”, and a complex and sweet flavor.  ‘Guardsman’ is one of the earliest scallions (ready in two months from sowing).  This English cultivar is a cross between a bunching and a bulb onion, with the shape of the first but getting a strong root system and large top from the latter. ‘Deep Purple’ is appropriately named for a base of that color.  ‘Parade’ is a beautiful upright, dark green, and uniform cultivar.  
The other onion relative, shallots, resembles a cross between an onion on the outside and garlic on the inside.  They are milder than either, with a sweet flavor that comes out even more when they are cooked or roasted.  Cook them with chicken, vegetables such as asparagus or peas, mushrooms, Swiss chard, or in casseroles. They’re a mainstay of French cuisine.
You can grow shallots from seeds or from “sets”—basically half-grown bulbs. Sets are more expensive, but easier and give a quicker harvest. To start shallots from seeds, sow indoors 8 to 10 weeks before the last average frost date for your area.  Transplant in mid-spring, spacing 2 inches apart.  Or you can sow one inch apart in the garden, 2 to 4 weeks before the last frost.
To grow from sets, separate the sections or “cloves”, planting these in early spring about 6 inches apart.  Press them in the ground so the pointed side is up, and just sticks out of the ground. Use a site and culture similar to scallions.  As plants grow, you can mound up soil around the base of plants.
You can harvest shallots when the leaves have begun to turn brown and fall over. This is generally about 90 to 120 days from planting.  Each clove should yield 10 or more shallots. Dig bulbs gently, loosening the soil with a spading fork, then wipe off any dirt.  Place them on trays or a wire rack in a shady, dry and well-ventilated place, for three weeks or more to “cure”.  Then pull off the dried tops, and store in a cool (50 degrees F is ideal), dry place away from apples and tomatoes.  (These give off ethylene gas, which causes bulbs to sprout.) 
Save the largest shallot bulbs for replanting next year.  Or try planting in fall for a spring crop, mulching with at least 6 inches of straw or leaves. 
‘Saffron’ is a hybrid shallot with bright coppery skin and pale yellow flesh, and it stores for 6 months or more.  ‘Ambition’ is a large French cultivar that also stores well. Similar is ‘Conservor’, just slightly longer, with a reddish brown outside and pale pink inside.  ‘Camelot’ is attractive with its dark red exterior and white interior. 
A new pest of onions and its relatives is invading the North Country.  The leek moth, originally from Europe, lays eggs which hatch into small caterpillars or larvae.  These chew on leaves early in the summer, and later in the summer larvae tunnel into plant bases, causing them to rot.  Covering plants with a lightweight fabric row cover should keep this moth away.

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