Neem oil is derived by pressing the seed kernels of the neem tree. It is very bitter with a garlic/sulfur smell. A single seed may contain up to 50 percent oil by weight. Neem oil is an excellent moisturizing oil and contains various compounds that have insecticidal and medicinal properties. It is used in making shampoos, toothpaste, soaps, cosmetics, mosquito repellants, creams and lotions, pet products like pet shampoo, etc. It also contains vitamin E, other essential amino acids and some percentages of fatty acids. Neem oil is used for treating many skin diseases viz. eczema, psoriasis, skin allergies, etc. and is being studied for making contraceptives in India. A compound found in Neem Oil and neem leaves extract- ‘Salannin’, has been proven to be safer but more effective insect repellant than DEET. Neem provides protection from not only mosquitoes, but also from biting flies, sand fleas and ticks.
Neem oil has been used for hundreds of years in controlling plant pests and diseases. Many researches have shown that the spray solution of neem oil helps to control common pests like white flies, aphids, scales, mealy bugs, spider mites, locusts, thrips, and Japanese beetles, etc. Neem oil also works as a fungicide and helps control powdery mildew. Some people have also experienced good results with neem oil spray on black spot. Orchid owners use pure neem oil spray to control pests like mealybugs, spider mites, etc. One of the main ingredients in neem seed oil is Azadirachtin that works as an insect growth regulator, thus preventing the larval stage to molt into an adult. As neem is very bitter in taste, it also works as an antifeedant thus making the leaves sprayed with it very distasteful for the bugs to eat, and the bugs choose to starve themselves than eat the leaves treated with neem.
Recommended ratio for making spray solution: mix 1 teaspoon pure neem oil in a quart of warm water and 1/4 tsp. liquid dishwashing soap (non-antibacterial, mild soap e.g. ivory). Shake it well to mix properly. Quantity of neem oil can be increased proportionately for making spray in larger quantities
Neem oil can be added to regular shampoo for controlling itchy scalp and dandruff
For pets, neem oil can be added to pet shampoo to kill ticks and fleas or the area where the pets usually use can be treated with neem oil spray
Unfortunately making pure neem seed oil requires considerable knowledge, skills and equipment.
Luckily there are other ways to extract the active substances from neem seed kernels. Organic solvents work best, that’s what is used most in industrial neem extract production. At home you can use either an easily available organic solvent (ethanol or methanol), or, even simpler, use water!
Yes, watery neem seed extract is quite effective. Most of the active ingredients in neem seed kernels are not very water soluble, but because they are so concentrated in the seeds even a watery extract will be very powerful.
A word of warning: neem seed oil and neem seed extracts have a very strong, pungent smell!
Making large amounts of a watery neem leaf extract.
- Cover the neem leaves with water at a ratio of one kilogram of leaves to five liters of water.
- Let the leaves soak over night.
- Don’t heat or boil the mix. Heat will actually lower the Azadirachtin content of the neem leaf extract.
- The next day grind the leaves in the water, and then strain the mixture. (I usually do this in two steps: first I strain the whole brew through something like cheesecloth to remove most of the sludge. Then I filter it through a proper filter paper. The result is a clear liquid.)
If you want to make neem leaf extract to use for spraying in the garden you can soak the neem leaves for up to a week. It makes the extract more effective, but phew, it smells foul!
If you want to use it elsewhere, for example add it to your bath water for skin protection etc., then you want to strain it before it starts smelling. You can keep neem leaf extract in a dark bottle in the fridge for several days. However, depending on the use it’s much safer to make it fresh.
Neem face wash
Boil neem leaves in water for a few minutes. Use the same amount you would use for strong cup of tea. Strain, let it cool down, and use it as an antibacterial face wash several times a day. Beneficial to treat acne and pimples.