Start chervil early in the season; direct sow as soon as the ground can be worked. Thin to 4-8" spacing. Harvest when young by cutting the outer stems as you would cilantro or parsley; warming temperatures will initiate bolting. Sow in successions in the spring for a steady supply. Once the plant has produced a seed stalk, the quality of taste declines. But, if you allow the plant to go to seed, you will have fresh chervil very early the following spring, as the plant naturally germinates in the cool of fall and easily overwinters in zones 5 and up.