6 Common Fall Container Garden Pests and How to Control Their Spread

As summer transitions into fall, gardeners often face a new set of challenges in the form of container garden pests brought on by the inconsistent weather and lingering humidity from summer. There’s nothing quite as infuriating as seeing bugs and critters decimating your hard-earned new growth.

To help you maintain a thriving fall container garden, we've put together a list of some common fall container garden pests to look out for this season, how to recognize them and some simple, organic methods to control their spread.

Before we dive in, did you know that using rainwater for your container plants could be the key to unlocking lush foliage and even preventing plant pests and diseases? If you’re still getting any rain, try to collect some this season.

Here are some pests you should be on the guard for this Fall:

1. Aphids

If you’ve been gardening long enough, you’ve probably come across these hateful red critters at some point. Aphids have a broad appetite. They can target a wide range of container plants, including flowers, fruits, and vegetables like kale, tomatoes and peppers. If not arrested quickly, they can decimate the whole plant within days and spread to other plants.

As much as we hate aphids, though, their presence is usually an indication that something is off-balance in your garden. They attack underwatered or overfed, stressed plants, so keep up a good watering schedule and make sure to space out your fertilizing.

Signs of Infestation:

● Yellowing or curling leaves with characteristic bumps on the surface of the leaves

● A sticky, dewish residue on leaves

● Clusters of small, pear-shaped insects on the stems and the underside of the leaves

Control:

● Mix water, dish soap, and a pinch of cayenne pepper, and spray on affected plants.

● Spray a neem oil solution on the affected plants to kill the bugs in the early stages of the infestation.

● For more serious infestations, prune and discard affected plants.

2. Cabbage Worms

Cabbage worms are velvety green larvae of cabbage white butterflies. They are aptly named for being especially fond of cruciferous vegetables like kale, cabbage, and broccoli. They affect these plants most when they are in their budding stage, but can only do minimal damage to adult plants. Companion planting with thyme has been found to aid in preventing cabbage worms.

Signs of Infestation:

● Chewed or irregularly shaped holes in leaves

● Small, green caterpillars on the plants

Control:

● Handpick and remove caterpillars from your plants.

● Apply Bacillus thuringiensis (BT) spray to repel them.

● Catch them with yellow sticky traps

● Apply neem oil spray in the early stages

● There’s an old farmer’s remedy to sprinkle rye flour over the plants to dry up the larvae

3. Spider Mites

Spider mites are a container gardener’s worst nightmare, and for good reason. They are more active during the hot, dry months and can wreak havoc on a wide range of plants, especially strawberries, lemons, tomatoes and flowers - especially roses.

Signs of Infestation:

● Stippled or yellowing leaves that fall off

● Fine webbing on the undersides of leaves

● Tiny red or brown mites crawling on the foliage

Control:

● Spray down affected plants with a mixture of water and liquid soap and wipe off the mites

● Treat small patches of the plant with rubbing alcohol

● Quarantine plants with serious spider mite infestations until after treatment. Do not add them to the

compost pile.

4. Slugs and Snails

Just one slug or snail can devour an entire container garden, and they don’t discriminate between foliage or flowers. They will eat pansies, violas, peppers, monsteras, and lettuces, and clear any foliage in their way within hours. Snails and slugs are part of the ecosystem, so we can never really get completely rid of them. However, you can create an environment that attracts their natural predators (like birds and insects) to keep their population under control.

Signs of Infestation:

● Watch for their food trail, characterised by irregularly shaped holes in leaves and a silvery slime trail on the soil or pots.

Control:

● Place copper tape or diatomaceous earth around the base of containers to deter slugs and snails.

● Set up beer traps by burying containers filled with beer to attract and drown them.

● Pick the snails off from the leaves and either rehome them or crush them

● Create barriers around your containers with crushed eggshells, coffee grounds, sawdust or wood

shavings so slugs and snails cannot crawl over.

5. Scale

There are more than 8000 insects that can cause what we know as plant armageddon - scales. Scales are characterized by brown bumps that sometimes attract cloudy-looking fungi to the plants, compounding the problem. Scale can infest humidity-loving indoor plants, and vegetables like cabbage and flowering plants.

Signs of Infestation:

● Look for tiny, oval-shaped, brown or white bumps on the underside of leaves, stems, or branches.

Control:

● Prune and discard heavily infested plant parts, and make sure they don’t come in contact with your other plants. Disinfect pruning shears and gloves after handling scale-infested plants.

● Apply a mixture of neem oil and liquid soap to affected areas to suffocate the scales.

● Quarantine infested plants until after the scales have gone away

6. Whiteflies

Whiteflies are often attracted to container plants like chrysanthemums, poinsettias, and ornamental peppers. They suck out the sap from the plants and leave them vulnerable to other pests

Signs of Infestation:

● Check for small, white, moth-like insects that flutter around your plants when disturbed

● Sticky honeydew residue on leaves

● Yellowing, drying and falling off leaves

Control:

● Hang yellow sticky traps near your plants to catch adult whiteflies.

● Use neem oil spray to repel them.

Garden pests don’t operate in isolation, they’re usually a sign that your plant is under distress in some other way. Usually, this is due to overwatering, prolonged dryness, overfertilizing or an unbalanced soil pH. As the seasons change, adjust your watering and plant care schedule to the changing weather. By recognizing the signs of infestation and applying organic control methods, you can protect your container plants and keep them healthy so they can thrive through fall and winter.

Have you motived any pests in your container garden lately? How do you get rid of them?