Neem Tree

The neem tree (Azadirachta indica) is a fast-growing, mostly evergreen tree from the Indian subcontinent and a member of the mahogany family. It is famous for its bitter leaves and seed oil, which people have used for centuries to keep insects away, make soap and protect crops.

Scientific Classification & Quick Facts

Common name	Neem tree
Scientific name	Azadirachta indica
Kingdom	Plantae
Phylum	Tracheophyta
Class	Magnoliopsida
Order	Sapindales
Family	Meliaceae
Genus	Azadirachta
Conservation status	Least Concern
Type	Fast-growing evergreen tree
Habitat	Dry to semi-humid areas; poor, stony or dry soils
Native range	India, Burma and the Indian subcontinent
Size	15 to 20 m tall
Lifespan	Can live over 200 years
Colours	Fragrant white flowers
Special feature	Natural pesticide and medicine; oil from seeds

What Is Neem?

Neem is also called nim, nimtree or Indian lilac. It grows wild across India and nearby countries such as Pakistan, Nepal, Bangladesh, Sri Lanka and Myanmar (Burma). Because it copes so well with heat and drought, it has been planted in many other warm parts of the world, especially in Africa, the Middle East and Southeast Asia.

In India the tree is treated almost like a village pharmacy. Its twigs, leaves, bark, flowers and seeds all have traditional uses, and you will often see neem trees lining streets and shading schools, temples and backyards. You can read more about the plant’s many traditional uses on our neem page.

What Does a Neem Tree Look Like?

A neem tree usually grows 15 to 20 meters (about 50 to 65 feet) tall, and very old trees occasionally reach 35 meters or more. It has a short, sturdy trunk with thick, furrowed bark and wide-spreading branches that form a rounded crown. Neem keeps its leaves for most of the year, but in a severe drought it may drop almost all of them to save water.

The leaves are pinnate, meaning each leaf is made of many small, toothed leaflets lined up along a central stem, a bit like a feather. A whole leaf is about 20 to 40 cm (8 to 16 inches) long.

In spring the tree produces drooping clusters of small, white, sweet-smelling flowers. These turn into smooth, olive-shaped fruits about 1.5 to 2.8 cm (roughly half an inch to an inch) long. Ripe fruits are yellow, with a thin skin, a bittersweet pulp and a hard shell holding usually one seed. Neem looks a lot like its close cousin, the chinaberry tree (Melia azedarach).

Photo by: Forest & Kim Starr

Where Does Neem Grow?

Neem loves hot, tropical and subtropical places. It does best where yearly rainfall is about 400 to 1,200 mm (16 to 47 inches), but its deep roots let it survive in even drier spots if there is groundwater below. It grows in poor, stony, shallow and even salty or alkaline soils, as long as the ground drains well. Fallen neem leaves can also improve tired soils over time.

Large neem plantations exist in West and East Africa, including Nigeria, Senegal, Burkina Faso, Kenya and Tanzania, where the trees give shade, firewood and shelter from wind on the edge of deserts. In a few places, such as parts of northern Australia, neem spreads so easily that it is now treated as an invasive weed.

How Long Does Neem Take to Grow?

Young neem trees grow slowly in their first year, then speed up. A tree usually starts bearing fruit after 3 to 5 years and is fully productive after about 10 years. A mature tree can produce dozens of kilograms of fruit a year, and neem trees are thought to live for 150 to 200 years or more.

Photo by: Abdullah Al Mamun

Growing Neem at Home

Neem is a tropical tree, so it cannot survive frost. In warm climates it can be planted outdoors. In cooler places it is best grown in a large pot that can be brought indoors before the weather turns cold, ideally kept above about 10°C (50°F).

• Seeds: Use fresh seeds, because neem seeds lose their ability to sprout within a few weeks. Plant them about 1 cm (half an inch) deep in small pots in spring or summer. They usually sprout in 1 to 3 weeks.
• Soil: Choose a light, sandy, well-drained mix. Neem hates soggy roots.
• Sunlight: Give it as much sun as possible. Young plants struggle in deep shade.
• Watering: Water thoroughly, then let the soil dry out before watering again. Overwatering is the most common way to kill a neem, because wet soil leads to root rot. Water even less in winter.
• Feeding: A diluted liquid fertilizer every few weeks in the growing season is plenty. Skip it in winter.
• Pruning: Trim young trees in spring to shape them, or prune lightly in late summer to keep a potted tree small.

Pests and Problems

Neem is usually very tough and rarely bothered by pests, which is not surprising for a tree that is itself a natural insect repellent. However, some sap-sucking scale insects can attack it. In parts of Africa, especially around Lake Chad, one scale insect has become a serious pest that can weaken or kill young trees.

How People Use Neem

Almost every part of the neem tree is useful.

Natural Pest Control

Neem seeds and leaves contain a substance called azadirachtin. Rather than killing insects instantly, it puts them off eating, upsets their growth and stops them developing properly. Neem products work against hundreds of kinds of insects, mites and other pests, and they break down quickly in the environment. They are generally gentler on helpful creatures than many chemical sprays, but they should still be used carefully, for example not sprayed directly on bees.

Neem Oil and Neem Cake

Neem oil is pressed from the seeds. It is used in soaps, shampoos, skin lotions, pet shampoos against fleas and ticks, and some mosquito repellents. What is left after pressing is called neem cake. Farmers dig it into their fields as a fertilizer that also helps protect roots from tiny soil worms called nematodes. In India, urea fertilizer is coated with neem oil so that its nitrogen is released more slowly and less is wasted.

Leaves, Twigs and Bark

Dried neem leaves are tucked among stored grain, books and woolen clothes to keep insects away, and fresh leaves are used as mulch. For generations, people in India have chewed neem twigs as natural toothbrushes, and neem extracts are still added to some toothpastes. The bark contains tannins, which have been used for dyeing and tanning leather.

Timber and Firewood

Neem wood is reddish-brown, fairly hard and naturally resistant to termites and rot, so it is used for furniture, fence posts and carts. It also makes good firewood and charcoal.

For Animals

In some regions neem leaves are mixed into feed for goats, sheep and cattle in small amounts, and farmers have traditionally used neem to help protect their chickens and other livestock from parasites and disease. A vet should always be consulted before using any home remedy on animals.

A Word About Safety

Neem has been traditionally used for skin problems and many other health complaints, and scientists are still studying how well it works. That does not make it safe to swallow. Neem oil in particular can be poisonous if eaten, and it is especially dangerous for babies and young children. Always ask a doctor before using neem as a remedy, and keep neem oil out of reach of children and pets.

Neem tree FAQs

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