How to keep pests away from your delicate basil plants

Basil is a wonderful herb, adding flavor to pizza and pasta sauce and anything else you want. Fresh, homegrown basil is a delight. What isn’t so delightful, though, is when pests start eating your basil. Here are some tips for figuring out what your pest is and what to do about it.

What animals and insects eat basil?

Aside from people, there are a variety of things that eat basil. Japanese beetles, slugs, and aphids are the most common basil pests. Other pests include whiteflies, spider mites, caterpillars, and thrips. Animals aren’t likely to be eating your basil, although some damage could occur if an animal is eating the bugs off your plant.

The easiest way to identify what is eating your basil is by sight. The pests listed above all have relatively distinct appearances. Beetles have a hard exoskeleton; whiteflies resemble tiny white moths; aphids are small, oblong, and either green or orange; and spider mites are very small and round.

If you can’t see a pest, you can make an educated guess based on the holes in the leaves. Slugs and caterpillars leave large, uneven holes; Japanese beetles don’t eat the veins of the leaf; and aphids, whiteflies, and spider mites make smaller, smoother holes.
Aphid on leaf

How do I get rid of pests on my basil plant?

For larger insects that you can see, such as beetles, caterpillars, and slugs, you can remove them by hand. For smaller pests, there are a couple options. If you can see them, you can spray them off with a water hose. Smaller pests typically stay on the underside of the leaves, so angle your hose up at them. Make sure your pressure isn’t hard enough to damage the plant.

If you can’t see them, there are sprays that will kill on contact as well as protect your plant from future pests. If you’re using a chemical insecticide, make sure to read the directions carefully. Some need to be shaken first, others need to be mixed with water and diluted. Applying chemicals incorrectly can damage the plant or even hurt you, so be careful.

A more environmentally friendly solution is neem oil or spray. Neem oil is derived from the neem tree, or Indian lilac, a relative of mahogany. Since it is natural and not chemical-based, it has a lower impact on the environment in general and, more specifically, your plant. It is still effective as an insect-repellant, though.
Basil plant growing in a mug

Can I bring my basil plant indoors?

You can bring your basil indoors, and this can help protect them from pests. However, basil plants need a lot of light. To be healthy and happy, a basil plant needs roughly six hours of sun. In most climates, this means you’ll need to find your sunniest window. Plants typically don’t like sudden shifts in climate, so if your house is much colder or warmer than the outdoors, you may need to match your temperature to the outdoors and gradually bring it back to normal.

What do holes in basil leaves mean?

If there are holes in your basil leaves, it means that something is eating your plant. Remove the leaves with holes first, even if they are small holes. Insects that eat your plants will sometimes lay eggs near where they have eaten, and others are small enough to hide on the leaf or in the hole. Damaged leaves will typically die anyway, so don’t feel bad about removing them. Additionally, remove any leaves that are brown, abnormally moist, limp, or smell off. Dry, brown leaves are already dead, while moist, limp, and smelly leaves are rotting and likely moldy.

Basil has such a wonderful flavor, it’s no wonder so many insects enjoy it as much as we do. You can kill those critters in a few simple ways, but prevention is just as important. A properly cared-for, healthy, happy basil is naturally more resistant to pests than a sad, poorly tended basil. Make sure your basil gets plenty of light, and don’t overwater it! At the first sign of pests, act quickly to remove the damaged leaves and the pests themselves. With this information in your tool kit, you can get rid of pests and get back to pesto.

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