When I read about organic gardening, I see a lot of references to neem oil. What is it, and how do I use it in my garden? -Sherry

Neem oil is made from the seeds of the neem tree (Azadirachta indica), which is native to India. Since ancient times, the neem tree has been prized as a sacred remedy and important ingredient in Ayurvedic medicine. In the garden, neem oil boasts a powerful insecticidal ingredient, azadirachtin, which makes it a great organic choice for controlling a variety of problems.


    a mosquito taking a bite
    Neem oil can repel insects such as mosquitos. (WikiImages, Pixabay)

    Uses for Neem Oil

    Neem oil can be used to treat a number of garden ailments, including:

    • Insects: Neem oil kills or repels many harmful insects and mites, including aphids, whiteflies, snails, nematodes, mealybugs, cabbage worms, gnats, moths, cockroaches, flies, termites, mosquitoes, and scale. It kills some bugs outright, attacks the larvae of others, and repels plant munchers with its bitter taste.
    • Fungus: Neem oil is also effective in preventing fungal diseases such as black spot, anthracnose, rust, and mildew.
    • Disease: As if that wasn’t enough, neem oil also battles viruses that can harm plants.

    bug on plant
    Neem oil can keep garden pests away without harming your plants.

    Advantages of Neem Oil

    Neem oil is a popular choice in organic gardens because it is:

    • Nontoxic: As long as it isn’t sprayed directly on them, neem oil is nontoxic to beneficial garden insects such as predatory wasps, honeybees, earthworms, ants, spiders, ladybugs, and adult butterflies. Neem oil is considered nontoxic to humans, birds, and other animals as well (see below) and can be used on fruits, vegetables, and flowering plants.
    • Organic: Neem oil is plant based and easily available from organically grown neem trees.
    • Biodegradable: Neem oil breaks down quickly and leaves no lasting residue.

    Exterminator in protective gear spraying garden in a backyard.
    Using a pump sprayer such as this can help you apply the neem oil and water mixture. (Adobe Stock Image)

    How To Apply Neem Oil

    Neem oil concentrate is usually mixed with water and sprayed on both sides of plant leaves. Because oil and water tend to separate, you’ll need to keep your solution well stirred. You can also mix it with insecticidal soap for a double whammy. Neem oil is bottled in different concentrations, so follow the instructions on the package to get the right proportions of oil to water.


    Insecticidal soap made naturally from plants. (Antonio Gravate)

    Other Uses for Neem Oil

    If you’re concerned about the safety of neem oil compared to other products in your garden, consider that neem is often used as an ingredient in:

    • Cosmetics
    • Shampoos (including pet shampoos for flea/tick control)
    • Natural insect repellents
    • Alternative medical remedies for antiseptic, antiviral, antifungal, and anti-inflammatory uses

    The only health cautions for neem oil relate to actual consumption of the oil, and garden use does not appear to pose any known health hazards. As with any chemical—organic or synthetic—use neem oil only in moderation when needed, and wash all veggies and plants thoroughly before eating.


    Further Reading

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    Danny Lipford

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    Danny Lipford is a home improvement expert and television personality who started his remodeling business, Lipford Construction, at the age of 21 in Mobile, Alabama. He gained national recognition as the host of the nationally syndicated television show, Today's Homeowner with Danny Lipford, which started as a small cable show in Mobile. Danny's expertise in home improvement has also led him to be a contributor to popular magazines and websites and the go-to source for advice on everything related to the home. He has made over 200 national television appearances and served as the home improvement expert for CBS's The Early Show and The Weather Channel for over a decade. Danny is also the founder of 3 Echoes Content Studio, TodaysHomeowner.com, and Checking In With Chelsea, a décor and lifestyle blog.

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