Lavender has a brisk, herbal flavor and in olden days was used as an antiseptic. Lavender water was used to clean wounds as late as World War I. Today, most of us are familiar with lavender sachets used to repel moths, or lavender water used to fragrance linens.
Lavender grows as tiny purple flowers along a stiff stalk. Rub the flowers off the stalk and discard most of the stalks, which contain essential oils that can be too pungent for cooking. (Note: the stems, not the flowers, are used in perfumes.)
In the garden, lavender is often teamed up with herb rosemary, and indeed it can be used in cooking wherever you might use rosemary. Pack a tablespoon or two into the cavity of a roasting chicken, or use it in a dry rub on a leg of lamb. The fragrant, herbal flavor of lavender can be distilled into vinegars or other liquid concoctions.