Do you use the same vegetable almost daily in your cooking? I bet you do, when you think of all the members of the Onion family as "one vegetable." Onions et cetera have been cultivated for centuries and used internationally. Whether the dinner bell rings for rice and beans, stir fry, or Zwiebelkuchen, some sort of allium comes to the table. And we should be eternally grateful that they accept the invitation. Onions are loaded with nourishing, disease reducing compounds.1
The family of onion-ey plants is called Alliaceae. or alliums. Some alliums have showy flowers, and those appear in catalogs of flowering bulbs. In this article, we'll discuss the alliums known for flavor rather than bloom; in fact, blooms are mostly undesirable for the edible onion gardener.
Onions, leeks, garlic, shallots, scallions, chives: all are Alliaceae
Members of the allium family are easy to recognize. They share the same basic "body type": thin grasslike leaves that all emerge from one point on a thickened stem or bulb, and fleshy roots emerging from a small area on the bottom of the plant. From beefy leeks, down to delicate chives, the form is similar. They may bloom, the bloom consisting of one tall stalk with an explosion of tiny flowers at the tip.
For the most part, alliums do their active growing in the cooler part of the year. Most are planted in early spring in the North, and spring or fall in warmer zones. Soil for alliums should be slightly acidic; a pH of about 6.0 to 6.8 is best according to various sources. Gardeners can opt to start with seed, young plants, dry sets (which are like baby onions,) or cloves (for garlic only.) Onion sets crop up in all kinds of stores each spring. Onion seed, of one or two kinds, is included in packet displays. Most other alliums are bought from growers as seed, young plants, sets (dry baby onions) or as heads.
Onions are heavy nitrogen users and like a rich soil and plenty of water. Allium plants grow leaves first, and then the leaves feed the root growth. That explains why these "root crops" need nitrogen. Keep alliums weed free and cultivate with care; they have shallow roots. The onion family is a fairly fuss free one for home gardeners. Alliums are not prone to the same diseases that plague many other vegetables. Include alliums in your crop rotation to help break the cycle of Verticillium wilt and other diseases or pests. Deer and rabbits avoid alliums. Some gardeners plant garlic as a deer deterrent.
Starting with easy alliums
Chives and garlic make easy first alliums for the new gardener. Chives can be started from seed or as small transplants in the herb display at the nursery. Both common chives and garlic (Chinese) chives are perennial. They make long-lived herbs, or can accent the corners of the vegetable patch. Garlic is planted in fall, and immediately begins to grow roots and a few leaves. In spring, the young garlic plant takes off, grows more leaves, develops a head, and is ready to harvest by early summer.
Use sets (dry baby onions) for an easy introduction to onion care. Look for onion sets in the garden section of the store each spring. Plant them just an inch deep, in fertile organic soil, and close together in rows. Pull and eat some when they grow to scallion size in several weeks, leaving room for bulbs to develop on the remainder. The bulbs should form on top of the soil.
Serious onion growing requires a degree of serious effort in selecting the right variety. This is more than picking "white, red, yellow or sweet" onions. For a major crop of onions, a gardener must consider planting location, climate, and each onion variety's "day length." For example, a table for choosing cutivars of onion in North Carolina shows that onions of various "day lengths" can be grown there, but each must be planted at a particular time of year to make a good crop. When planning to grow onions, seek advice for your specific location; knowing the latitude of your garden is a plus. The closest Extension Service should have specific recommendations for home gardeners. Reputable suppliers2 of onion seed, plants, or sets are generous with advice on choosing the right type of onion for the buyer's garden.
Whether or not you've mastered the growing of ordinary onions, the less common onion types can be great fun to grow. Leeks are planted in cool weather, have a long growth cycle, and are harvested in summer or fall. Bunching and multiplier onions form large clumps of scallions, or plentiful handfuls of small bulbed onions. Italian and French gourmet onions offer novel shapes and sizes. "Potato" onions create clusters of bulbs and can be harvested and replanted for a perpetual crop. Shallots are planted in early spring as cloves. Egyptian "top set" onions make tiny new onions on their flowering stalks, along with plenty of usable leaves. Elephant garlic is not exactly "just" a very large garlic, but it is eye-popping, easy, and tasty, too. Explore specialty catalogs and sites as sources for these intriguing onions and assorted alliums.
1. Nutrition and You. com http://www.nutrition-and-you.com/onion.html
2. Some resources for growing onions:
Dixondale Farms http://www.dixondalefarms.com/aboutus
Johnny's Selected Seeds http://www.johnnyseeds.com/default.aspx
Southern Exposure Seed Exchange http://www.southernexposure.com
Territorial Seed Company http://www.territorialseed.com/about_us
Table for selection of onion cultivars in North Carolina http://www.ces.ncsu.edu/hil/hil-18-a.html