The tropical origins dictate where basils grow best: a warm, sunny location where plenty of moisture is available. Basils require at least four hours of sun daily and should not be planted until night temperatures are in the upper 50s F. (13 to 15 C).
Basils will tolerate a wide variety of growing conditions but do best when planted in rich, well-drained soil. To provide proper air circulation and discourage disease, plants should be set about a foot apart. Pinch back the top of the tender stems to encourage a bushier plant.
Keep an eye out for flowers and prune them off immediately to promote further leaf growth.
Water regularly -- at least one inch per week. Basils grow quickly and are heavy feeders, so be sure to give them a dose of liquid fertilizer twice a month.
If you don’t have room to plant basils outdoors, or if you live in an area where summer evenings are cool, try growing basil in clay pots. It is one of the few flowering herbs traditionally raised as a potted plant. Gardeners in England often presented guests with a pot of basil as a symbol of good wishes.
We’re all familiar with the popular culinary basils including Genoa Green and Genovese. They are two of the best selections for pesto but some of these colorful varieties are also great choices for cooking and garden display:
African Blue basil -- Green leaves shaded with purple; leaf veins and stems are purple. A wonderful ornamental plant.
Red Rubin -- Rich, dark purple leaves have a clovelike spiciness. May be a bit strong for pestos.
Cinnamon basil -- Dark green, distinctively veined foliage, spicy aroma with a hint of cinnamon.