How to Grow Lemon Basil From Seed

Lemon basil is a warm-season herb that dislikes the cold, so let warmth set your timing. Start seeds indoors about 6 weeks before your last spring frost, then set plants outside only once nights stay reliably above 50F and the soil has warmed. You can also direct-sow once frost is well past and the ground is warm. Sow a fresh short row every few weeks for a steady supply of fragrant, citrusy leaves all summer.

Lemon basil is easy to start from seed. Sow the small seeds about a quarter inch deep in rich, well-drained soil or moist seed-starting mix, pressing them in gently for good soil contact. Keep the mix evenly moist and warm, around 70F, and seedlings usually appear in 5 to 10 days. Give them bright light so they grow stout rather than leggy, and once plants have a few sets of true leaves, thin or space them 8 to 12 inches apart in full sun.

Lemon basil is a fast, tender grower that rewards frequent picking. Water to keep the soil evenly moist but never waterlogged, watering at the base in the morning so leaves dry quickly. Give it full sun and a light feed, and pinch the tips once plants reach 6 inches to keep them bushy. It flowers quickly, so pinch off the small white buds as soon as they appear to keep the leaves tender and aromatic. Like all basils it is frost-tender: gardeners in the Upper Midwest and Northeast should hold off until nights stay above 50 degrees and the soil warms to 60, while growers in the humid Southeast and along the Gulf get months of growth but should pick often and shear the plants back to head off the quick summer bolt.

Lemon basil makes a good garden neighbor, especially for tomatoes, and its citrusy scent helps deter many common pests. These four make especially good companions, and you can add any of them in one click:

Start picking once plants are 6 inches tall and bushy. Harvest by pinching whole stem tips just above a pair of leaves rather than stripping single leaves, which prompts the plant to branch and produce more. Cut in the morning when the citrus oils are strongest, harvest often to delay flowering, and never take more than about a third of the plant at once.

Add lemon basil near the end of cooking or use it raw, because its citrus aroma cooks off fast. It is wonderful with fish and chicken, stirred into rice and noodle dishes, and scattered over salads. Steep the leaves into iced tea, lemonade, or infused water, and try it in an unexpected pesto or a simple herbal syrup for summer drinks. Use it the day you pick it for the brightest lemon flavor.

• Bolting (flowering): lemon basil flowers fast. Pinch off flower buds as soon as they appear and harvest often to keep leaves tender.
• Cold damage: it blackens in a chill. Keep it warm and never set plants out until nights stay above 50F.
• Damping off: seedlings collapse at the soil line in cool, damp, still air. Sow in fresh mix, give airflow and bright light, and avoid overwatering.
• Yellowing leaves: usually overwatering or poor drainage. Let the top inch of soil dry between waterings and grow in well-drained soil.
• Leggy seedlings: too little light. Grow in full sun or under bright grow lights and pinch the tips to encourage bushy growth.