Neem oil, a natural remedy for controlling certain pests, is an organic pest control solution with many other benefits and uses.
Neem oil comes from the seeds of the neem tree (Azadirachta indica). This is a tropical evergreen tree .
Neem oil reduces insect feeding. It also disrupts their hormones, stopping the growth cycle and making it difficult for them to lay eggs.
Neem oil is particularly effective against insects that chew on leaves. The smell of it also naturally repels many other pests in the home and garden.
The Benefits of Using Neem Oil on Plants
Neem oil is a natural fungicide as well as an insecticide, and you may find it in a wide variety of garden and home products.
Its insecticidal and antifungal properties make it great for controlling multiple pests and plant diseases. Additionally, the de-oiled residue (neem cake) from crushed neem kernels has widespread use as an organic fertilizer .
Now that you know what neem oil is, below are the main benefits and uses for it in the garden.
1. Treatment of Bacterial and Fungal Disease Issues
Many gardeners use it for the treatment of fungal and bacterial diseases of plants.
The antifungal and antibacterial qualities of neem oil can help keep the garden ‘clean’ by reducing or eliminating mildews, black spots, leaf spots, anthracnose, fire blight, rust, mold, and more.
Regular spraying of plants in and around the garden will help keep these problems under control.
2. Controls Pests
Used regularly throughout the year, neem oil can control a multitude of pests that destroy food crops and other plants.
Neem oil pesticides are often the first choice for organic gardeners. It is effective against many types of destructive bugs and pests, and you can apply it in several ways.
A spray solution around plants and directly on leaves will kill some pests. And as mentioned, it repels others, thereby reducing the number of garden pests.
The smell and taste are repugnant to most harmful insects and will repel them. Some garden pests that neem oil works against include:
- Leaf-footed bugs
- Aphids (greenflies)
- Spider mites
- Lace bugs
- Fungus Gnats
- Leaf miners
- Some beetles
- Spotted lanternflies
- Tarnished plant bug
- Squash bugs
Moderate applications can also benefit the soil by reducing harmful nematodes while leaving earthworms unaffected.
3. Natural Fertilizer
Because it works as a systemic insecticide when applied to the soil, neem oil acts as a fertilizer, thereby increasing the plant’s immunity.
Why is this so? It reduces nitrogen release, so plants are able to take up more nitrogen from the soil. This improves soil quality.
Neem oil is also very nutritious and makes for a great foliar fertilizer. Plus, neem cakes are a great NPK fertilizer for your garden.
4. Glossy Foliage
When used correctly, neem oil sprays leave foliage healthy and looking glossy. Indoor plants can especially benefit from neem oil used to clean the leaves.
It also works well for enclosed spaces like greenhouses. Just spray your DIY solution (recipe below) to dampen a rag and use it to wipe the top and bottom of each leaf.
How to Use Neem Oil in the Garden
Be careful when using it, as some irritation may occur on sensitive skin and in the eyes.
Make a homemade neem oil spray by combining 5 ml of neem oil, 2 ml of organic liquid soap, and 1 liter of water. Shake well and spray both sides of the plant leaves.
Alternatively, purchase a neem oil concentrate online or at your local garden center. Use it according to the label instructions.
For soil drench and foliar spray use, apply every three weeks as a preventative measure. But apply once a week to keep pests under control if there’s an infestation.
Light protective clothing is also advisable before applying it to plants. Also, avoid spraying near pregnant women and young children.
Additionally, do not use neem oil in hot weather, as it will likely cause foliage burns. It can also damage newly transplanted or stressed plants.
Spraying in the spring and other suitable times throughout the year can target the eggs and larvae of various pests.
Various ingredients can be found in neem oil.
One popular one is azadirachtin. This component is toxic to some pests, disrupting their molting process.
Other active ingredients include picrin, nimbin, and sialin .
What Plants Not to Use Neem Oil On
Generally, neem oil is safe for use on most plants. However, do not use it on herbs like thyme, cilantro, oregano, parsley, or dill.
It can also cause leaf burns when used on leafy vegetables such as lettuce, spinach, and arugula. Moreover, neem oil can block the pores of ferns’ sensitive leaves.
In general, high doses can burn plant leaves, so read the label carefully as it will list any restrictions.
How It Affects Beneficial Insects
Neem oil insecticides control bugs and pests that feed by sucking or chewing on plant leaves.
Therefore, if used correctly, it will not affect butterflies and bees because these insects do not eat leaves. Wasps and ladybugs that deal so effectively with aphids and other small insect pests are also unaffected by it unless sprayed directly on them.
That said, do not spray on blossoms or flowers that these pollinators might land on. And do not spray helpful insects with it.
Effect on Pets and Animals
It is considered safe for cats or dogs when used correctly. Various grooming products for pets contain nourishing neem oil.
Additionally, experts have experimented with the use of neem leaf meal in broiler rations in place of antibiotics .
However, some slight toxicity has been shown in fish, so do not use it near ponds, rivers, or waterbeds.
Effect on Humans
Studies have shown that neem oil is potentially toxic to children and adults if ingested .
However, for gardening purposes, you can use it right throughout the growing season, up until the day of harvest. Just be sure to wash your produce properly.
Where to Buy Neem Oil to Use on Your Plants
As you can see, neem oil is good for the garden in many ways. As a result, it is widely used in many agricultural products. The benefits of using it on plants are wide, but especially so for the organic gardener.