In Season

You'll Know These Onions by the Bulb

Which is which? If the bulb is rounded and pudgy, it's a spring onion; if it's straight and slender, it's a scallion. Both are members of the onion family.
Which is which? If the bulb is rounded and pudgy, it's a spring onion; if it's straight and slender, it's a scallion. Both are members of the onion family. (By Julia Ewan -- The Washington Post)
By Stephanie Witt Sedgwick
Special to The Washington Post
Wednesday, May 2, 2007

When you see a member of the onion family that is small and long and thin, colored green on the top and white on the bottom, what is it? Whether you answer scallion, spring onion or green onion depends on where you're from, but also on what you're looking at. This is one onion -- make that two onions -- with a huge identity problem.

With spring onions beginning to appear at farmers markets, the question needed an authoritative answer. Roy Brubaker, who with his wife, Hope, owns Village Acres farm in Mifflintown, Pa., knows his spring onions from his scallions, because his farm grows both.

There is a significant difference.

Scallions are long and thin, and the little white bulb at the bottom is straight and does not bulge outward. Brubaker likes to harvest his when the bulb is 1/2 to 3/4 inch in diameter. "If I left them in any longer, they'd get taller and stronger in flavor, but they'd never develop a bulb," Brubaker says. He and his workers plant the scallions in groups of five or six, and that's how they harvest, clean and bunch them for sale.

Spring onions have more of a bulb, and its size depends on how long the plant is left in the soil. Brubaker plants one seed per cell, sometimes two, then transplants them individually. If harvested while still babies -- which is done to thin out the beds or to cull the less-hardy plants -- they're spring onions; if left to grow, they develop into regular onions. "When the tops are all green and the bulbs about one to two inches, that's when we harvest for spring onions," Brubaker says. They are bunched in groups of two or three, cleaned and sold.

Confusingly, either type is sometimes referred to as a green onion, at least in this country. And the nomenclature gets even more complicated elsewhere. The British use the term spring onion for both spring onions and scallions, and Australians call both of them shallots, although to an American that's another member of this allium family altogether.

But enough with the names. Because there's an obvious visual cue -- the size of the bulb -- let your eyes decide, and go from there.

Does it matter? It sure does. A spring onion can be used in recipes that call for scallions, giving an extra boost of sweet onion flavor, but the reverse isn't necessarily true because scallion bulbs are so small.

"I choose spring onions for the bulb," says James Peterson, author of "Vegetables" (Morrow, 1998). Peterson cuts off and discards the green tops, then glazes the plump bulbs or roasts them alongside a piece of meat. Brian McBride, executive chef of the Blue Duck Tavern in the District's West End, likes them slowly braised or roasted.

Though scallions can be grilled, roasted or braised, they're usually sliced and diced and are often used raw. With their fresh, mild flavor, they are perfect for cold salads. They're a must in Asian cooking because they cook so quickly in stir-fries. Mexican food wouldn't be the same without them. Peterson loves what a handful of sliced scallions can do for a soup. "It just freshens the whole thing up," he says.

My hands-down favorite way to make sweet potatoes for Thanksgiving: roasted and mashed with sour cream and scallions.

Both varieties needs a good rinse, then the removal of the outer layer, any tough green stalks and the root. After that, the tender part of the green stalk and the white bulb, thin or fat, can be used -- although not necessarily for the same thing.

Scallions are available year-round in supermarkets, but not so spring onions. When you spot the latter this month at the farmers market, grab them and do your own taste test. Pretty soon you'll be roasting those bulbs with the rest of us, saving the greens for the salsa -- and reverting to scallions once spring is over.

Stephanie Witt Sedgwick, a former Food section recipe editor, can be reached Her In Season column appears the first Wednesday of every month.

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