Skip to main content

HappySprout may earn a commission when you buy through links on our site.

Everything you need to know about permethrin garden spray, what it does, and how it helps your garden

Are there any drawbacks to this popular insecticide? Find out here.

Pests are just a fact of life anywhere there are plants around to feed them. As such, pest control is an ongoing issue for most gardeners, but it can be hard to find a spray that works for you. If you’re new to gardening or just new to the pest control aisle, you may not have heard of permethrin before. If you’re confused about what permethrin is, where it comes from, and what it’s good for, then you’re in the right place. We’re here to clear up questions you have, starting with the basics.

A person with green and white gloves sprays a pest control solution from a yellow spray bottle onto some roses
LDprod / Shutterstock

What is permethrin?

Permethrin is a compound of three chemicals based on a similar compound, pyrethrin, found in flowers in the chrysanthemum family. Chrysanthemums produce pyrethrin as a form of natural pesticide. Permethrin is the synthetic form of this natural compound, so there are some slight differences between the ratio of each chemical in the spray versus in individual plants — namely, the ratio in each individual plant can vary, but the ratio used in sprays is consistent so that you always know exactly what you’re getting.

However, most permethrin garden sprays are not 100% permethrin. Permethrin is typically used as the active ingredient, but another chemical is added to extend its lifespan and make it more effective.

How is permethrin used?

Permethrin is available mainly in sprays, although some concentrates are available. The most common use for permethrin sprays is to spray it on a cloth to keep insects, especially mosquitoes, at bay during long hikes or gardening sessions. The permethrin soaks into the cloth and kills pests when they land on it.

It’s important to read the instructions that come with any pesticide you use, and permethrin sprays are no exception. Some permethrin sprays are made specifically for cloth, while others may not be safe for indoor use or may be designed for an overall lawn misting rather than for use directly on garden plants.

What pests are permethrin effective against?

Permethrin is effective against a wide range of insects, including ticks, mosquitoes, lice, mites, cockroaches, fleas, and flies. It works by interfering with the neurons of impacted creatures, causing paralysis and death. It does this on contact, meaning it keeps pests from nibbling your plants in the first place. It is even used in treating mosquito netting and is a main ingredient in some flea collars for dogs, although it isn’t safe for cats.

What are the drawbacks and limitations of permethrin?

In addition to killing pests, permethrin can also harm or kill beneficial insects, such as bees and other pollinators, and cats. If enough of it contaminates a body of water, it can negatively affect fish and other aquatic life. There are a few precautions you can take to limit the potential harm, though. Using permethrins on indoor plants, for example, can reduce both the number of pollinators exposed to it and the amount of pesticide that can potentially find its way into waterways. If you have a cat, keep your plants in an area your cat can’t access.

If you have outdoor plants that you plan on using permethrin on, you can use a pollinator net to keep pollinators away from your plants. You may be able to cover the blooms with a bowl and target the leaves with your spray, but this isn’t a foolproof plan.

Raised gardens with nets over the plants
Image used with permission by copyright holder

Where can you find reliable permethrin spray?

Your local gardening supply store will likely have several different permethrin sprays available, but if you prefer to get yours online, or if you’d like to go into the store with an idea of what brands to look for, here’s what to look for.

Before buying a permethrin spray, it is important to check what it’s designed to be used on. Many permethrin sprays are designed for use on cloth specifically, which is great if you’re looking to set up netting or a cloth barricade around your plants. However, this isn’t ideal if you just want something to spray on your plants.

One of our favorite multi-use products is Voluntary Purchasing Group Inc.’s

Hi-Yield Lawn, Garden, Pet and Livestock Insect Control

. It is a concentrate, not a spray, so you need to read the instructions carefully, but it does have a greater range of applications. One bottle can make quite a few batches of spray as well, meaning you won’t need to get additional bottles very often.

It’s important to remember that every pesticide has its benefits and drawbacks, and it’s up to you to decide which pest control method is right for you and your plants. A lot of pest controls boil down to trial and error, and permethrin is one of many options. Give it a try and see what you and your garden think!

Cayla Leonard
Cayla Leonard is a writer from North Carolina who is passionate about plants.  She enjoys reading and writing fiction and…
Don’t let these common plant pests ruin things: What to do when you find them
Watch out for these common plant pests
Aphids on the petals of a daisy

As much as we wish it weren’t true, houseplants and greenhouses aren’t exempt from pest problems. Since they’re inside, you don’t have to worry about deer or rabbits or squirrels chomping at the leaves, but bugs can still find their way indoors. Whether they buzz in through a window or hitch a ride on your pets, pests are sure to find your plants eventually. Some pests are more common across different species than others. Here are the most common types of plant pests to watch out for, and what you should do when you find them.
Mealybugs

Mealybugs are sap-sucking insects that cause gradual damage to your plants over time. Houseplants infested with this pest often exhibit yellowing leaves and leaf drop. They have a cottony appearance, which is obvious when contrasted against the green foliage and stems. For survival, they often nestle and cause damage in nooks and crannies like crowded stems or unfurled leaves.
Signs of an infestation
Because yellow leaves and leaf drop are signs of an array of problems, those things alone don’t indicate a mealybug infestation. What you want to look for, especially if some of the foliage starts to fall prematurely, are cotton-like spots on the stems and leaves. Mealybugs also leave behind a sticky substance that’s wax-like and powdery in appearance, so if your plant starts to look like it has a white film coating parts of it, chances are there’s a bug problem.
How to get rid of mealybugs so they don’t come back
Mealybug infestations can be handled in a variety of ways, depending on the size of the infestation and the kind of method you want to use. For smaller mealybug populations, you can use natural solutions like:

Read more
Everything you need to know about harvesting potatoes
All the facts about your potato harvest
Potatoes on the ground

Potatoes are one of the most versatile vegetables, with a nearly infinite number of ways to cook and season them. They’re also incredibly easy to grow and typically have large yields, so you can harvest plenty of potatoes even if you only have a single plant. How soon after planting can you expect that harvest, though? How do you know if a potato is ready to be harvested or if it needs more time? This guide will answer all your questions about how and when to harvest potatoes.
When is potato harvest season?

Depending on the type of potato you’re growing, harvest season ranges from late summer through fall. However, new potatoes can be harvested throughout summer. New potatoes, also called baby potatoes or early potatoes, are ones that have not fully matured. They are smaller but still delicious! Since they aren’t fully developed, they can be harvested at any point in the summer.

Read more
What is perlite (and why you need it for your plants)
What perlite is and how to use it
A metal seedling tray full of seedlings with perlite in the soil

When it comes to plant care, there are many different additives you can mix into soil to improve your plant’s health. Keeping track of what each additive does and figuring out which one is best for your plants can be tricky. Perlite is one common soil additive that you might be wondering about. What is perlite, how does it help your plants thrive, and are there any risks or drawbacks you should know about? This guide to perlite soil will answer all your questions, so you can decide if perlite is right for your plants.
What is perlite?

You might be familiar with perlite as a common additive found in potting soil. If you’ve ever been repotting a plant and found little white beads that feel a bit like Styrofoam, that was perlite. Despite its foam-like texture and color, perlite is actually a type of volcanic glass. It is naturally occurring and has high water content.

Read more