Harvesting, drying and preserving lavender
Both the flowers and foliage of lavender are fragrant, but it's the flowers that are dried and preserved for craft or culinary uses. Some growers claim the scent of English lavender becomes even sweeter after drying, but all dried varieties retain their scent for a year or more.
Harvest stems when approximately one-quarter of the flowers are open (aromatic oils are at their peak); remove leaves. Gather stems into small bunches with rubber bands or twine and hang upside down in a cool, dry, dark room for two to three weeks.
To store dried lavender for recipes, rub bunches of dried stems over a wide-mouthed bowl. Shake the contents of the bowl through a sieve or colander to separate the dust from the big bits. Store bits in a small canister. (Make sure the lavender you use for culinary purposes hasn't been sprayed with pesticide.)