What is Neem Oil?
Neem oil comes from the neem tree, a fast-growing and incredibly resistant species native to Asia. The tree’s oil, harvested from its seeds, has many helpful properties, including pest control. Unlike many synthetic pesticides, neem oil has a low toxicity rating, making it minimally harmful to beneficial wildlife, such as pollinators. It also has a low toxicity for humans. However, it’s still wise to avoid contact with the eyes. Also, limit direct exposure to the chemical unless you have carefully read the label and determined it is safe for skin, as some neem oil products contain additives that can be irritants.
Many gardeners know that neem oil is an effective natural pest control product, but rarely do they consider the multiple applications for this oil in the garden, around the lawn, and even within the home. Here are some neem oil uses for outside, inside, and around the house.
Neem oil repels a host of insects, including aphids, mealybugs, spider mites, thrips, squash bugs, and whiteflies. Unchecked, these tiny pests can do a lot of damage. One of the main components of neem oil, azadirachtin, adversely affects insect hormones that enable growth and reproduction. By applying neem oil to the foliage of infested plants, you can effectively reduce the insect population. Neem oil doesn’t provide instant results, though, so treating pest-ridden plants with this natural pesticide requires patience.
Control Destructive Nematodes
There are many species of nematodes, but the ones that bother plants are microscopic. While they’re related to roundworms, the nematodes in your garden aren’t a human threat. However, they can do a number on plants by damaging stems, roots, leaves, and flowers. They also spread disease. Neem oil can help combat destructive nematodes by putting a damper in the reproductive process.
Be aware not all nematodes are bad news; some can improve the soil and eat their unlikable cousins.
Ward Off Overwintering Insects
It’s bad enough dealing with insects during the growing season. But even if you manage to kill insects in the summer, many overwinter and come back with a vengeance. Use neem oil on dormant plant life to prevent overwintering pests from surviving and eggs from hatching in the spring. While some pesticides only work on pests at specific times during their lifecycle, neem oil can kill bugs at various stages.
Control Lawn Grubs
Japanese beetles are gross, bulbous insects that can seriously damage a lawn or landscape in their larval form. When they emerge, they’re capable of devastating food crops and ornamentals. The best way to target these hungry insects is to prevent them from setting foot on your lawn in the first place. Spraying the grass with neem oil keeps beetles from laying eggs, so grubs never show up to destroy your lawn.
Indoor Plant Protection
Neem oil is also incredibly useful for controlling houseplant pests. Even with careful inspection, it’s possible to bring pest-ridden plants into the home inadvertently. Understandably, many people have doubts about using pesticides inside, but neem oil is safe to use indoors. Simply spray the leaves regularly to control insect populations and prevent disease. Because neem oil is nontoxic, there’s no need to worry about the safety of children or pets.
Go-to in the Greenhouse
Similarly, you can also use neem oil to control pest and disease outbreaks in a greenhouse. The closed environment of a greenhouse is ideal for pest proliferation. Just one simulated plant can turn into a severe infestation. People are hesitant to spray highly toxic chemicals in an enclosed space, like a greenhouse, for obvious reasons. Neem oil serves as a viable alternative for indoor control of common greenhouse pests, like aphids and mites.
Fungal infections can be challenging. Many are incurable and, over time, stress plants so severely that they eventually die off. However, neem oil is an excellent fungicide that can both prevent and remove fungal infections from infected plants. It’s effective on fungal diseases like powdery mildew, leaf spot, rust, and scab. To get rid of a fungal disease, regularly spray the affected plant weekly until the infection is gone. Regular spraying also helps prevent fungal disease.
Killing pests is only half the battle. Many insect infestations also bring disease, including bacterial infections like fire blight. To combat this disease, which causes severe wilting and leaf burn, spray affected plants with neem oil during their dormant phase. Make sure to spray the plants all over to prevent the disease from overwintering.
Keep Mosquitos Away
Ouch! Mosquito bites are unpleasant, and they can also spread diseases like West Nile Virus. To keep mosquitoes away, you should inspect your property for evidence of standing water. Mosquitoes breed in these spots—often hidden from view. An additional tool for an anti-mosquito arsenal is neem oil. Spray neem oil insecticide on plants around your deck or patio area to discourage mosquitoes from hanging around. Additionally, pure neem oil can be applied to the skin to ward off these biting pests.
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