Pick a normal onion early in the growing season and you'll get a spring onion. Spring onions are useful for adding a marked onion note to dishes, particularly when used raw.
Spring onions should have dark-green leaves and fresh-looking roots. Choose firm bulbs with even-coloured skins and no signs of sprouting.
Serve spring onions in salads, or sprinkled over Chinese dishes (particularly steamed fish), or stirred into raita or traditional Irish champ (mashed potatoes speckled with chopped spring onions). They can also be brushed with olive oil and chargrilled whole.