Light. Thyme grows best with 6–8 hours of sun a day. Some afternoon shade helps it through the hottest months.
Water. Keep the soil evenly moist while it settles in, without overwatering. Once established it is drought tolerant. It does not tolerate wet soil or poor drainage.
Soil and feeding. It prefers soil that is not too rich, with a pH of 6.0–8.0, so it handles alkaline soil. Mix compost in at planting. It needs little fertilizer; too much weakens the flavor.
Size. Grows to about 6 in tall and spreads 6–16 in, so it suits rock gardens and the edges of pots.
Pruning. Trim it whenever it gets leggy, taking no more than one-third at a time.
Problems to watch. Overwatering causes root rot. Grow it in a pot or raised bed for air flow against powdery mildew, and spray aphids and spider mites with Insecticidal Soap.
Good to know. Plant in late fall or early spring. Flavor is strongest just before it flowers.
Sources: UF/IFAS Gardening Solutions: Thyme · UF/IFAS Extension Pasco County: Spice Up Your Life, A Beginner's Guide to Growing Thyme
