Neem oil for plants. Using neem oil in the garden.
It is not easy to find safe, natural, non-toxic pesticides for the garden that actually work. Everybody recognizes the importance of protecting our food, our families, and the biological world around us, but most organic pesticides aren’t very effective. That is, except for neem oil.
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What is neem oil?
Neem oil is pressed from the seeds of the neem tree, which is also known as nim tree or Indian lilac, or by its botanical name Azadirachta indica. It is a member of the Mahogany Family. It grows in tropical and subtropical areas of South Asia.
The neem tree is a beautiful and useful plant. Growing up to 130 feet (over 30 meters) tall, it can provide shade over 80 feet (more than 25 meters) out from its trunk. Once a year, it is covered with drooping white and fragrant flowers in panicles up to 10 inches (25 cm) long.
Neem trees are drought-resistant. Their shoots and flowers are eaten as a vegetable (although their bitterness requires some getting used to). Neem leaf and neem seed are used in skin-soothing soaps and shampoos.
And neem seeds and neem seed oil are unique natural pesticides. Neem doesn’t kill insect pests. Instead, it repels insects from the leaves where it is sprayed. If the insects stay on the plant, they lose their appetite and don’t eat it. Their hormones are disrupted, so they don’t lay their eggs.
Insects that stay on plants sprayed with neem either die of old age or starve to death. If insects have already been laid on a plant that is then sprayed with neem, they won’t hatch.
These properties make neem the ideal garden insecticide. It gets rid of pests on the plants gardeners want to protect. But it leaves insects in other locations so birds and other wildlife can still feed on them.
There is one more way that neem is a great product for your garden. Neem leaves and neem seeds are collected by villagers in India. Fairtrade organizations make sure workers in India get fair payments for collecting neem. The Neem Foundation makes sure that the people who do the work of collecting neem are always in contact with new buyers and markets for their work.
Using Neem Oil in the Garden
One of the reasons gardeners turn to neem is for natural protection against spider mites. Neem also deters aphids, mealybugs, scale, and whiteflies. Neem can also control diseases like black spot, root rot, and sooty mold.
The most effective way to apply neem oil is as a drench to the soil just before seedlings emerge from the ground. When neem is applied as a drench, it becomes a safe systemic pesticide. Every part of the young plant is protected from insects that otherwise would destroy it.
Neem won’t protect young plants from rabbits, squirrels, and birds that eat tender shoots. That’s part of its attraction. Neem is nontoxic to wildlife. Runoff water with neem in it won’t harm fish. And neem as a drench protects plants for 21 days.
A situation in which neem can be very helpful is stopping armyworm damage. It can save plants from attack by caterpillars. And once a plant has become established, spraying it with neem diluted in water (follow directions on the label) can keep bugs in check indefinitely.
What are the steps by step directions for using neem?
- Always test neem on a single plant before you spray a whole bed, patch, or field. If there is no leaf damage on that single plant 24 hours later, then you can assume it is safe to use that neem product on more plants of the same kind.
- Always spray neem in the evening or on a cloudy day. This way it is absorbed into the plant rather than evaporating.
- Avoid using neem in extreme temperatures. This prevents additional stress to plants. Extreme heat or cold are both contraindications for using neem.
- Make sure leaves are completely coated. It is especially important to get the undersides of leaves coated with neem to stop aphids and mites.
Neem Oil Insecticide
Neem oil is an effective insecticide that will prevent pest insects from eating your garden plants, while still allowing pollinators to do their job.
Neem oil is the most effective against soft-bodied insects. This is great because many of the garden pest insects are soft-bodied insects like caterpillars or worms.
Use neem oil to keep insects from chewing your plants and damaging your crops.
The insecticidal part of neem oil is most effective at repelling tomato and tobacco hornworms, spider mites, corn earworms, whiteflies, thrips, aphids, cutworms, armyworms, cabbage moth caterpillars, mealybugs, and mites.
Neem Oil Fungicide
Not many insecticides also share fungicidal properties. Neem oil can help prevent both pest insects and fungal problems.
Neem oil is effective against various disease-causing fungi, mildew, and rust. These problems are common issues and can easily be avoided with neem oil. Rust is a disease that’s common on many plants, including green beans. Use neem oil to help keep rust and other diseases away from your plants.
Neem Oil Foliar Spray (Neem Oil Spray for Plants)
Neem oil is found in many garden centers as a foliar spray. To use neem oil foliar spray, be sure to use it on the leaves and stems of the plants that you want to protect. Avoid spraying the fruits or flowers of the plant to allow pollinators to access the blooms.
When you’re spraying the plant, cover the top and bottom of the leaves with neem oil.
Apply neem oil to the plant in the shade or during a cloudy day. This allows the plant to absorb the neem oil, making it more effective. If you spray the neem oil when the sun is out, the neem oil will evaporate before the plant can absorb the neem oil.
When it’s applied correctly, neem oil is effective for up to 21 days.
Where to Buy Neem Oil
Most garden centers carry neem oil. You can also buy it quickly off of Amazon.
Is neem oil safe to use?
Neem is deadly to insects that chew on leaves and stems. It is not toxic to insects that feed on nectar or pollen. It will not kill butterflies or ladybugs. However, if you are releasing ladybugs into your garden, time the release, so they won’t be eating aphids that were recently (in the last four days) sprayed with neem, just to be safe.
Neem sprayed on plants won’t kill bees, but at least one scientific study shows that bees won’t visit plants sprayed with neem as often. (The same thing can be said about other pesticides.) If you have an issue with getting enough bees to visit your plants, don’t spray them with neem while they are in flower.
There has been considerable recent scientific investigation into the possible effects of neem on plants, animals, and people that aren’t targets of its use. The only possible side effect of neem scientists have uncovered is that it may reduce the chances of conception in pets and people exposed to it.
There is research in India and France on using chemicals concentrated from neem as a contraceptive. But gardeners would not be exposed to high concentrations of those chemicals.
Neem is the most versatile and least toxic of all the insecticides available to gardeners. Use it mindfully, and enjoy the benefits of neem for your garden.
Interested in mixing up neem oil spray?
Watch the video below to learn how to use neem oil in recipes.