Neem is a fast-growing evergreen tree in the mahogany family, native to the Indian subcontinent and naturalized across tropical and subtropical regions. It is the primary commercial source of neem oil-a broad-spectrum biopesticide extracted from its seeds-and is central to South Asian agriculture, horticulture, and traditional medicine.
Under good conditions the tree reaches 40–65 feet in 15–20 years, forming a dense canopy effective for shade in hot climates. It tolerates drought, heat, and poor soils once established, but cannot survive frost; temperatures below 35°F cause dieback and sustained freezing kills the tree. The root zone releases allelopathic compounds that can suppress germination of some nearby plants. Prune young trees to a single central leader; neem tolerates hard cutbacks and resprouts readily. In zones below 10, large container-grown specimens can be overwintered indoors in full sun.
Azadirachtin, concentrated in the seeds, is well-documented as an insect growth regulator and antifeedant and underpins OMRI-listed organic pesticides used globally. In Ayurvedic practice, bark, leaves, and oil are applied to skin disorders, fever, and oral hygiene-chewed neem twigs function as antibacterial toothbrushes across South and Southeast Asia. Young leaves appear in South Indian and Southeast Asian cooking, used in chutneys, stir-fries, and rice dishes despite their pronounced bitterness.
Growing it indoors up north? See the indoor care guide - light, water, and the rhythm that keeps it flowering as a houseplant.