ONION, Allium Ceps (family Liliaceae), a hardy bulbous biennial, which has been cultivated from time immemorial. It is one of the earliest of cultivated plants; it is represented on Egyptian monuments, and one variety cultivated in Egypt was accorded divine honours. It is commonly cultivated in India, China and Japan. A. de Candolle regards it as a native of western Asia.
For good results the onion should be grown in an open situation, and on a light, rich, well-worked soil, which has not been recently manured. The principal crop may be sown at any time from the middle of February to the middle of March, if the weather is fine and the ground sufficiently dry. The seed should be sown in shallow drills, io in. apart, the ground being made as level and firm as possible, and the plants should be regularly thinned, hoed and kept free from weeds. At the final thinning they should be set from 3 to 6 in. apart, the latter distance in very rich soil. About the beginning of September the crop is ripe ; the bulbs are then to be pulled, and exposed on the ground till well dried, and they are then to be stored in a cool, dry place.
About the end of August a crop is sown to afford a supply of young onions in the spring months. Those which are not required
for the kitchen, if allowed to stand, and if the flower-bud is picked out on its first appearance, and the earth stirred about them, produce bulbs of large size. A crop of very large bulbs may also be secured by sowing about the beginning of September, and transplanting early in spring to very rich soil. Another plan is to sow in May on dry poor soil, when a crop of small bulbs will be produced ; these are to be stored in the usual way, and planted in rich soil about February.
To obtain a crop of bulbs for pickling, seed should be sown thickly in March, in rather poor soil, the seeds being very thinly covered, and the surface well rolled; these are not to be thinned, but should be pulled and harvested when ripe.
Onions may be forced like mustard and cress if required for winter salads, the seeds being sown thickly in boxes which are to be placed in a warm house or frame. The young onions are pulled while quite small. For statistics regarding the commercial produc tion of onions in the United States see under VEGETABLE.