How to Use Neem Oil to Protect Plants From Pests

Neem seed oil is a vegetable oil derived from neem trees (Azadirachta indica), which are native to India. Organic neem oil contains an active ingredient called azadirachtin, which acts as a natural pesticide for organic gardening. Gardeners use neem oil on their houseplants and outdoor vegetable gardens as an insecticide, fungicide, and miticide. The environmental protection agency (EPA) considers neem oil safe for indoor plants and use around pets. Other neem oil products include mixtures with other insect-repellent essential oils and neem cakes, a type of soil amendment.

Neem oil works as a preventative method as well as pest control for an existing infestation. Use neem oil during the morning or evening hours. Avoid using neem oil during the middle of the day, as the combination of neem oil and direct sunlight can burn the plants. Neem oil is effective throughout the growing season, as it can kill pests during every stage of their lifecycle, including eggs, larvae (also called grubs), pupas, and adults.

Neem oil kills a wide variety of insects, including aphids, mealybugs, whiteflies, Japanese beetles, leafhoppers, thrips, fungus gnats, and other garden pests like spider mites and nematodes. Neem oil can also kill fungal diseases like powdery mildew, black spot, scab, anthracnose, and leaf spot. Neem oil is generally safe for beneficial insects that do not feed on the plants’ leaves, like ladybugs, pollinators, and earthworms.

Purchase a ready-to-use neem oil insecticide or mix your own DIY neem oil spray for your organic garden needs.

1. 1. Gather your materials. Buy cold-pressed neem oil, liquid soap, a spray bottle, and a gallon of water.
2. 2. Combine water with a small amount of soap. Mix a gallon of warm water with a teaspoon of liquid soap or insecticidal soap, which acts as an emulsifier for your mixture.
3. 3. Add a small amount of neem oil. Add one to two tablespoons of pure neem oil to your mixture.
4. 4. Apply the mixture to your plants. Use a foliar spray bottle to apply your neem oil mixture to one small section of your plants. Wait twenty-four hours. If there is no damage from the mixture, you can then thoroughly mist your indoor and outdoor plants, spraying directly onto plant leaves.
5. 5. Reapply the mixture as needed. Use neem oil biweekly as a preventative measure. If you’re trying to control an active pest infestation, spray your plants with neem oil every week.

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