Caren White is a Master Gardener and instructor at Home Gardeners School. She has been associated with Rutgers Gardens for over a decade.
I’m an organic gardener and when I am looking for organic solutions to problems that I am encountering in my garden or among my houseplants, neem oil is frequently recommended.
What is Neem Oil?
Neem oil is the oil that is obtained from the seeds or fruit of the neem tree. The oil is extracted from the seeds or fruit in either of two ways. It can be pressed from them or extracted using solvents. Cold pressed neem oil is the preferred form for use in organic gardening. The oil resulting from extraction using solvents is inferior to the cold pressed oil. Neem oil can be red, yellow, golden, brown or greenish brown. It smells like a cross between garlic and peanuts.
Neem oil is used for personal care, household use, on pets and as an insecticide and insect repellent.
What is a Neem Tree?
The neem tree is native to the Indian subcontinent including present day India, Pakistan, Bangladesh, Sri Lanka, Nepal and the Maldives. It is a drought tolerant evergreen that can reach a height of 66 feet. In the face of severe drought, the trees will drop their leaves. They survive dry conditions via their long roots which seek out sources of water underground. Neem trees grow best in areas with annual temperatures between 70⁰F and 90⁰F. They can tolerate higher temperatures. Low temperatures of 39⁰F will kill the trees.
The flowers are white and arranged in panicles. Neem trees are self-pollinating because both male and female flowers exist on the same tree. The resulting fruit is oval and yellowish white. Each fruit contains two to three seeds.
How to Use Neem Oil For Personal Care
Neem oil is used in many personal care items. It is used in the hair to relieve dry scalp or dandruff and as a conditioner to prevent frizz. The oil is also effective against head lice. It can be used to treat fungal infections of the skin and nails, as a skin conditioner, and to treat rashes, psoriasis and sunburn.
When using for personal care, it is always best to test the oil on a small spot on your skin to see if you are sensitive to it. Most people can use the oil directly on the skin, hair and nails, but some people with sensitive skin will experience redness or rash. If you are sensitive to neem oil, use it mixed half and half with another cold pressed oil such as coconut oil or almond oil.
If you don’t care for the scent of neem oil, mix a few drops of your favorite essential oil into your mix to give it a more pleasant fragrance.
How to Use Neem Oil Around the House
Thanks to its fungal killing properties, you can spray neem oil in the places around your house that are prone to mold and mildew. You can also add the oil to your everyday spray cleaners for an extra boost of germ killing.
How to Use Neem Oil on Pets
The use of neem oil on pets is a little controversial. It is purported to be an effective flea and tick repellent as well as a treatment for mange and ringworm.
There is no scientific proof that neem oil is an effective treatment for mange or ringworm. It is also not effective in repelling ticks. As a flea repellent, it is not as effective as the chemical repellents that are popularly used. Vets recommend that you use neem oil in addition to regular flea repellent and not as the sole flea repellent. To apply it to your dog, you can use a neem oil shampoo or spray it on your pet using a mixture of 1 part neem oil to 10 parts olive oil.
Neem oil should never be used on cats. It is toxic to them.
How to Use Neem Oil on Plants
There is no controversy on the use of neem oil on plants. It is effective and with a half-life of one to two days on plants, it is safe to use on edibles. It is non-toxic for humans, pets (except cats) and other animals, birds, fish, earthworms and beneficial insects. The only insects that are harmed by it are insects who bite or suck on plants, not the beneficials that pollinate your plants or eat harmful insects in your garden.
Neem oil works by disrupting the hormones in the effected insects preventing them from eating and molting. It is also an effective larvicide. The limonoids in neem are insect repellents, repelling common garden pests such as aphids, cabbage worms, mealy bugs, thrips, mites and whiteflies.
Neem oil should be used in diluted form on plants. To make your own spray, mix 2 teaspoons of neem with a few drops of dishwashing liquid in a gallon of water. Spray on your plants making sure that you spray both the tops and undersides of the leaves. You will need to spray every few days because the short half-life of neem.
My Experience Using Neem Oil
After hearing so much about neem oil, I was eager to try it for myself. I purchased Southern Ag Triple Action Neem Oil and mixed it according to the directions. I first used it on a bay laurel tree that was indoors for the winter and was infested with mealy bugs. I sprayed the leaves being careful to cover both the tops and the undersides. While I was spraying, I shook the spray bottle a few times, as directed, to keep the oil and the water properly mixed. Because neem is a natural product, I didn’t expect to see any results immediately so I was surprised the next day to see that some of the mealy bugs had died overnight. I sprayed once more three days later. All of the mealy bugs were dead within a week.
Encourage by this, I next tried using the spray in my shower which is prone to mold. Again, I observed results within 24 hours. I now spray my shower two or three times a week to keep it mold free. I can’t believe I spent so many years using toxic chemicals in a vain attempt the destroy mold when all I needed was a gentle, natural produce like neem!
Questions & Answers
Question: Do I mix water or soap with oil, for the spray cleaner?
Answer: For an ordinary spray cleaner, I would just add water. The soap is added to sprays for plants to help the neem oil adhere and smother the insects.
Question: Are Neem trees found in Cameroon?
Answer: Yes, Neem trees are being farmed in the northwest and southwest areas of Cameroon.
© 2018 Caren White
Larry W Fish from Raleigh on April 18, 2018:
I have never heard of a Neem tree or Neem oil. It is an interesting read. I always love how Mother Nature has blessed us with so many natural products.