Onions (Allium cepa) can be raised from seed sown outdoors in March, but most home gardeners use sets – small bulbs planted in late March or April, which are quicker and more reliable. Push sets into loose soil so that only the tips show, 8–10 cm apart in rows 25 cm apart; birds and frost sometimes lift them, so check and replant. Choose a sunny spot with free-draining soil that has not been freshly manured, as fresh manure produces soft necks that rot in store. Keep the bed weeded, since onions compete poorly, and water only in dry spells until the bulbs swell; stop watering once they begin to ripen. When most of the foliage has yellowed and flopped over, usually in July or August, lift the bulbs on a dry day and let them dry in the sun or an airy shed for about two weeks before storing. Winter onion sets planted in autumn give an early crop the following summer. Onions deter carrot fly but are poor neighbours for peas and beans.