Skip to main content

How to protect your plants from fall garden pests

Keep garden pests at bay this fall

Woman kneeling harvesting tomatoes
encierro / Shutterstock

Pests can do a lot of damage if they’re given free rein over your garden. This is especially true in October, when the cooling temperatures leave some plants vulnerable, increase the appetites of some pests, and drive others to make winter homes in your garden.

If you’re concerned about how your garden will survive through the fall, you aren’t alone. Don’t worry, though. We’re here to tell you everything you need to know about what pests might be a threat this fall. We'll also tell you how to spot them, prevent them from taking over, and get rid of them if they're already around. Best of all, you can probably set up a good pest defense system with common items you already have on hand!

Recommended Videos

Difficulty

Easy

What You Need

  • Undyed wool

  • Leaf mulch, coffee grounds, or egg shells

  • Copper tape, wire, or mesh

  • Bird feeder

  • Bird-friendly plants

  • Water source, such as a birdbath

  • Small dish or tin

  • Beer

  • Pesticide or capsaicin spray

Depending on the climate where you live, you’re likely to still have garden pests in the fall. If your local climate is very warm this time of year, the fall garden pests will still be actively eating your plants. This makes them easier to find, but it results in more damage to your plants.

On the other hand, if the fall is fairly cool where you live, you’re more likely to see pests go into dormancy or hibernation for winter. This makes them much harder to find and destroy, but it also means you don’t need to worry about plant damage until spring. You’re likely to see the same pests no matter the climate, but your prevention and treatment options will be slightly different.

Garden slug
Image used with permission by copyright holder

Identifying slugs and snails

Slugs and snails are both common fall pests. They primarily target leaves and fruit, but they’ll eat just about anything. Two sure signs of slugs and snails are large holes in leaves and trails of slime. They both lay eggs on the undersides of low-lying leaves in the fall. These eggs will hatch a couple weeks later. Young slugs and snails will then wait out the winter beneath any foliage that remains in the garden.

Cutworm curled on ground by young plant
Image used with permission by copyright holder

Identifying cucumber beetles, potato beetles, and cutworms

Cucumber beetles, potato beetles, and cutworms all hibernate through winter under the soil in your garden. Cutworms are easy to differentiate. They look like small, gray-brown caterpillars, and they're easily identified by the way they cut down plants by chewing through the stem.

Cucumber beetles and potato beetles can wreak havoc on a fall garden. They get their names because they especially love munching on cucumbers, potatoes, and potato relatives like eggplants and tomatoes. Both types of insects fairly small and have yellow backs. Potato beetles are striped, while cucumber beetles can be striped or spotted. Cucumber beetles tend to be slightly longer than potato beetles.

Three slugs eating leaves
Image used with permission by copyright holder

Deterring slugs and snails

Slugs and snails can be kept out of your garden in a couple different ways. Since they have soft bodies, things with rough, coarse textures can be used to keep them out. And yes, salt will work, but it's best to avoid it because salt can also harm plants and the soil.

Step 1: Set up a barrier of undyed wool around the plants you wish to protect.

Step 2: Instead of wool, you can set up a barrier of leaf mulch, coffee grounds, or eggshells.

Step 3: If the above steps don't work, set up a barrier made of copper tape, wire, or mesh around vulnerable plants. The copper reacts with slug and snail slime to give them a little jolt. The jolt is small enough that not all slugs and snails are deterred, but many are.

A yellow cucumber beetle with black spots on a leaf
Erik Agar/Shutterstock

Deterring cucumber beetles, potato beetles, and cutworms

Barriers can help keep cucumber beetles, potato beetles, and cutworms out, too. Cutworms are also soft-bodied and likely to react to rough textures, but height is beneficial for all three. A small border that extends a few inches beneath and above the surface of the soil can help significantly.

slug drinking from a beer trap
Image used with permission by copyright holder

Deterring slugs, snails, and beetles

A general preventative measure you can take is to encourage predators to visit your garden. For these pests in particular, you’ll have the best luck with birds. Here's how to set up an environment birds will love so that they'll come and eat your plant's predators for you.

Step 1: Set up bird feeders, plant bird-friendly plants, and provide a water source, such as a birdbath.

Step 2: Limit noises from power tools or other machinery.

Two large brown slugs eating a plant
Image used with permission by copyright holder

Getting rid of established pests

If it's too late to deter the pests because they've already set up shop in your garden, here are some ways to get rid of them.

Step 1: Catch and remove.

If you only see a few pests, you can simply pick them up and remove them. However, this isn’t the most efficient way, especially with slugs, which eat primarily at night.

Step 2: Set up a beer trap.

Fill a small dish or tin with beer and leave it out overnight, near where the slugs and snails have been doing most of their snacking. They'll be attracted to the yeast in the beer, especially the non-alcoholic varieties. When they come to take a drink, some will fall in and be unable to get out. Set up multiple traps around your garden for the best results.

Step 3: Use pesticides.

Because slugs and snails aren't insects, pesticides won't actually work on them. However, they'll work on cucumber beetles, potato beetles, and cutworms.

Step 4: Use capsaicin spray.

If pesticides aren’t your style, you can use capsaicin spray instead. This is a natural compound found in peppers, and most pests find it unpleasant to smell or taste.

Step 5: Turn the soil.

Once the weather cools and pests begin burrowing into the soil to sleep, turn over the top layer of soil. You only have to flip the first two inches. This leaves the sleeping pests exposed to the elements and to predators.

Now you’re prepared to protect your garden from all sorts of fiendish pests. The slugs, snails, beetles, and cutworms plaguing your garden won’t know what hit them. Using these tips, your October harvest will be safe at last. Plus, if you take action now, you’ll have significantly fewer pests to deal with when spring arrives.

Cayla Leonard
Cayla Leonard is a writer from North Carolina who is passionate about plants.  She enjoys reading and writing fiction and…
The best bulbs to plant in spring for lasting beauty in summer and fall
Add these bulbs to your garden for summer flowers
Stargazer lily bloom

Early-blooming spring bulbs like crocus flowers are among the first flowers to bloom every year, followed closely by many other spring annuals and perennials. By the time summer arrives, many flowers have already stopped blooming, leaving your garden a sea of green. That doesn’t have to be the case, though. You can plant bulbs in spring for gorgeous flowers all throughout summer and sometimes even into fall. Here are some of the best bulbs to plant in spring to keep your garden looking vibrant and vivacious all year long.
Calla lily

Calla lilies, also called arum lilies, are known for their tall, narrow stems, broad leaves, and elegant, spiral, cup-shaped flowers. Whether seen growing in a garden or as part of a cut flower display, calla lilies are striking. While they are not true lilies, they do come in many of the same colors. They can grow in similar conditions to true lilies, although they are slightly less cold hardy and thrive in full sun to partial shade. You can even grow your calla lilies in containers and indoors, although you should take care not to let your pets chew on them.
Crocosmia

Read more
Purple plants that will make your garden pop this season
Want more purple in your garden? Try these gorgeous plants and flowers
A field of lavender flowers

Purple is a popular color when it comes to flowers, and it's easy to see why. With lighter shades that can relax and soothe you, darker shades that add depth, and bright purples that are exciting and cheery, there is a purple flower for any garden. For flower bed layering, purple blooms can brighten shady gardens or add depth to a vibrant one, depending on the shade of purple. Whether you're looking for a single purple flower to round out your garden or want to dedicate an entire garden to your favorite color, here are the purple flowers you should look for!
Lavender

We couldn’t write a list of purple plants and not include lavender! Lavender is an incredibly hardy plant that's typically perennial in climate zones 5 through 9. Its delicate purple blooms and calming fragrance are highlights of its appeal, but they aren’t the only ones. Lavender is also an easy plant to take care of.

Read more
DIY compost bin: How to make one from a 5-gallon bucket
Here's how to set up a compost pile in a bucket — your DIY guide
A kitchen compost bin

If you want to compost at home to reduce food waste or improve your garden's soil, then learning how to make a compost bin might be at the top of your list. There are many fun and creative ways you can build a compost bin, but one of the easiest ways is to start with a 5-gallon bucket. If you want to know how to make a compost bin for your home and garden, this guide will help you get started on a DIY compost bin.

Read more