Onions can be grown from seed or sets (small bulbs). Sets are more costly, and there is a smaller range of cultivars available, but they are quick, reliable and a good choice for beginners.
When to Start: Early spring
At Their Best: Midsummer
Time to Complete: 1 hour
Locate a planting site with excellent drainage. Stretch a line of string between two pegs to make a straight row. Use a rake to form a shallow furrow, and plant the sets 6 inches apart, with the tips protruding. Weed regularly, and water during dry spells.
Onions are ready for harvesting in midsummer, when the leaves turn yellow and fold over. Lift them and place in a cool, airy place to dry out for a couple of weeks. Use any with thick necks right away, and store the others for later.
Excerpted from How to Grow Practically Everything
© Dorling Kindersley Limited 2010