Regular readers will know that I am a great fan of neem oil and it was one of the products that provoked the most queries when we were recently at the Homes and Gardens Show, so I thought it might be helpful to many of you to explain a little about it and its usage.

Neem oil is an environmentally friendly fertiliser, fungicide and insecticide, all rolled together into the perfect package – just one of many of Mother Nature’s miracles!

It is extracted from the azadirachta indica, more commonly known as the neem tree, a native of India, where it is locally known as the Divine Tree or Heal-All-Tree. Indian farmers have traditionally used the neem tree for centuries, extracting its many beneficial properties. It is used on a huge range of crop plants, primarily sugarcane, banana, coffee, tea, citrus, rice, cotton, turmeric, cardamom, pepper and various other herbs and spices as well as ornamentals. Because it is non-toxic, it is safe to use on all types of plants and cropping can take place immediately after application.

In the West we can fairly commonly buy neem oil now but, in India, they make much more use of it. Cakes are made of compacted neem seed (which contains the highest concentration of azadirachtin)  and are crumbled under plants to act as a fertiliser and pest repellent. The leaves of the tree are used to enrich the soil, counteract alkalinity and repel insects. Every Indian backyard would have a neem tree. It repels flies and lice from chickens, the bark was used in the tanning process and the extremely aromatic wood is used in charcoal production. Neem oil was also used as a general antiseptic for skin infections, sores, burns and ulcers; and it is used in the treatment of diarrhoea, malaria, diabetes, leprosy, jaundice and as an excellent mosquito repellent.

Sadly, during colonisation by the British, French and Portuguese, the usage of neem by the natives was scorned and ridiculed. Traditional farming and husbandry methods were wiped out and neem trees fell into disuse. How ignorant we were! Science now totally backs up the wisdom of those traditional ways. Gandhi was a great believer in the value of neem and it was largely through his efforts that trees were re-planted, small scale farming re-introduced and, in more recent times, the marketing of neem products. Today some 14 million neem trees are growing in India with a potential to produce 3.5 million seeds each year; 700,000 tonnes of oil can be extracted from that though, in practice, much less is produced simply because of poor marketing/lack of demand/slow take-up by Western markets.

The compound, azadirachtin, extracted from the seeds deters insects and changes their sexual maturity pattern so that they never become sexually active; thus plagues of insects are stopped. It has been proven that 165 insects avoid neem; these include flies, mosquitos, caterpillars, grasshoppers, locusts, lice, fleas, ticks, ants, geranium moth, palm beetle, citrus leaf miner, aphids, thrips, scale insects, red spider mite and vine weevil – an impressive list and one that covers most gardening problems! ‘Good’ insects are not affected because they do not eat the plant in any way. Likewise, mammals are unaffected. Furthermore, a 1% solution of neem oil/water acts like a raincoat on plants preventing entrance of fungal and bacterial spores that are wind and rain borne. It gives 95% protection.

 Prevention by insect and fungal/bacterial attack is achieved with a weekly foliar spray of 1% solution. If you have an existing problem, increase this solution to 5% for three or four weekly applications, then drop it to the preventative mix of 1%. Do make sure that your neem oil is pure and 100%. Used thus, you’ll have no need for any chemicals.

The tree is a member of the mahogany family and its cousin, melia azederach, the chinaberry or Persian lilac tree, is commonly used as a Spanish street tree. You’ll notice that it is never attacked by insects! Sadly, the neem tree seems to be unavailable in Spain (though I keep trying!). It is an evergreen tree that likes warmth, happy up to 45C, and it becomes very drought resistant. It will not, however, tolerate frost. It should be possible to grow in milder areas here. The springtime flowers are pale-pink, star-shaped and sweet smelling; the fruits resemble olives, yellow-brown when ripe.

Remember, it is totally organic so can be applied to all your fruit, veg. and ornamentals without any detrimental effect to us. In fact, it’s said to be 100 times less toxic than a cup of coffee! We have a guy that buys it to rub onto his snakes to deter lice and a woman that applies it to her acne but the majority buy it because it’s organic and because it really works!