Allium cepa
Family: Alliaceae

The onion is probably one of the most well known of all vegetables. Onions and garlic were used by the ancient Egyptians and today are used both as separate vegetables and as flavor­ing throughout the world. Onions are eaten raw, cooked as accompaniments to meats, or added to stews, curries, sauces and soups. They come in a range of shapes- round, flattened or globular-and the skin colour may be white, brown, yellow, red or purple. Some varieties have a strong, pungent flavor, while others, like the red- or purple-skinned Spanish onion, are quite sweet. Although true perennials, they are grown as annuals and are classed as early, mid-season or late for purposes of harvesting. Failure with onion-growing is often caused by planting the wrong variety for the season. Some varieties do not store well, and it is important to select the type that best suits your purpose.

Cultivation

Sow seeds in well-drained soil that has been liberally dressed with manure or com­post about two weeks before planting. Unless the soil is known to be alkaline, apply about half a cup of lime or dolomite per square metre (yard) to the planting area.

Sow seed in spring in drills about 2 cm (¾ in) deep in rows 30 cm (12 in) apart. Thin seedlings first to about 5 cm (2 in) apart and then later to about 10 cm (4 in). The thinnings can be used to flavor soups or salads. Onions can also be grown from sets (tiny bulbs) planted in spring and, for novice gardeners, are easier than sowing seeds.

Weed control is essential and should be ongoing. All-purpose fertilizer can be applied in bands along the sides of the rows if growth is quite slow. If the soil has been well prepared, this may not be necessary.

Onions for immediate use can be pulled or dug out at any stage. Do not pull onions for storage until the tops have browned and toppled over. Pull plants over to expose the bulbs to the sun, or spread them on trays to dry in the sun or in a dry, airy, sheltered place. When the outside skin is quite dry, cut off the stems 2-5 cm (1-2 in) above the bulb. Make sure bulbs are dry before storing, or they may rot.

Climate

Onions are very hardy and are suited to zone 5 and above. Climates with hot, dry sum­mers are best, but not essential.