Thyme (Thymus) is easy to grow in full sun and well-drained soil. Prune away winter-killed stems in spring and then feed plants lightly with a balance fertilizer. After bloom fades, shear back spent flowers, cutting 1-2in into the leaves to keep plants compact and to encourage new growth. In the West, prune plants at any time to keep them dense. In the South, plants may "mug off" in summer heat and humidity. Thyme is rarely troubled by pests or disease. English Thyme (T. vulgaris) is perennial in Zones 4-9; French Thyme (T. vulgaris) in Zones 4-10; and Lemon Thyme (Thymus x citriodorus 'Variegata') in Zones 6-8.