How to prune thai basil

Start pinching once the plant reaches 15 cm; remove flower spikes as soon as they emerge. Cut or pinch the stem just above the highest pair of leaves you want to keep. Remove entire flower spike clusters at their base. The plant will branch vigorously from each cut node.

Every 1–2 weeks; more frequently in hot weather when bolting accelerates. Thai basil (Siam Queen) requires the same pinching discipline as Genovese but is somewhat more bolt-tolerant. Pinch growing tips regularly and remove purple flower spikes before they fully open — the flowers are edible but signal the plant is shifting to seed production. Kept well-pinched, Thai basil is more robust and longer-lived than sweet basil.

Cut or pinch the stem just above the highest pair of leaves you want to keep. Remove entire flower spike clusters at their base. The plant will branch vigorously from each cut node.