Most herbs are ready to be harvested just as the flower buds first appear.
The leaves contain the maximum amount of volatile oils at this stage of growth, giving the greatest flavor and fragrance to the finished product. To extend the use of herbs into the winter months, plan to harvest and dry various herbs during the summer and fall. Their fragrance makes this early task quite enjoyable. Annual herbs can be cut back quite severely during harvest. Using a sharp knife or pruning shears, cut just above a leaf or a pair of leaves, leaving 4 to 6 inches of the stem for later growth.