Updated on December 11th, 2024
The soil had been rich. That spring, I had piled heaps of the coffee-brown earth in my hands. It had felt loose and fluffy, as though it was already making room for the roots that it yearned to hold. I remember inhaling its rugged, clean scent. The dirt had wedged its way beneath my fingernails, painted the beige cuffs of my sleeves shades of browns and tangled its hearty dust into the coarse hairs of my beard.
Yet, come early November, that same garden felt naked, cold and gray. Weeds were seizing territory. Rolls of strawberry cages lay tightly tangled within the arms of vicious, prickly weeds that harbored them with joy. Deer had gaily tugged away any threads of success, attacking the once-tender baby lettuce and spinach leaves and leaving the roots of other plants to simply wither away on the dark earth.
I was gone too long. My ambitious adventures had taken over the practicalities of my life. Yet, I sensed a small ripple of hope as I watched a cutworm make its way across the broad underside of a cabbage leaf. There were bugs—garden bugs that I could study.
Why garden pests are a winter problem
As the temperatures drop, some insects are making plans to survive the winter—right in your garden. These pests may seem harmless now, but come spring, they’ll unleash their destructive appetites. Proper identification is key to stopping them before they settle in and cause havoc next season.
Below, we’ll uncover the five key culprits: what they look like, which plants they target, the damage they cause, and—most importantly—how to eliminate them effectively.
Note: There are other pests that will attempt to overwinter in your home. These little miscreants must also be dealt with. Protect your home.
What do these bad bugs look like—and how can you stop them
Understanding your pests is the first step to regaining control of your garden. Here’s what to look for, which plants need protection, the damage these bugs cause and how to eliminate them effectively.
- What do these pests look like? Proper identification is critical—without it, there can be no effective treatment.
- Which plants do they attack? Each pest has its favorite plants they’ll voraciously target and devour.
- What damage do they cause? Will they leave chewed leaves, wilted stems or entire plants destroyed? Learn the warning signs before it’s too late.
- How can you get rid of them? Act quickly to eliminate these pests before they make your garden their home—and your plants their dinner.
What are the bad bugs on my garden plants?
Aphids
Quick identification: Aphids are small, pear-shaped, soft-bodied insects that are typically green, yellow, black or gray. Some may have a waxy or woolly coating, and their young (nymphs) look similar to the adults.
Plants they feed on: If you’re seeing small bugs on your squash plants, thoroughly check your other plants. Common aphids target a wide variety of plants, including:
- Fruit trees
- Melons
- Vine-grown vegetables (e.g., cucumber, pumpkin, melon)
- Underground vegetables (e.g., potato, beet)
- Leafy vegetables (e.g., lettuce, chard, bok choy)
- Houseplants
- Herbs
Damage they cause: Aphids pierce plant parts to suck out the fluid inside, then excrete honeydew, causing sooty mold in the process. Check your garden for yellowing leaves, yellow spots or curling leaves that have a sticky substance when touched. In early spring, their numbers will explode as weather conditions favor their breeding efforts and aphid damage will peak.
Quick fact: Aphid presence can cause considerable damage to your rose bushes. Plant alliums to protect your rose bushes.
How to get rid of this pest: To bring these sap-sucking, plant-killing miscreants to their eternal resting place (which is probably just a few mere inches from where they’re dining), use the Insect Buster and dust the infested plants with Dust to Dust Plant-Powered Insect Powder.
Dust to Dust eliminates pests by breaking down the protective wax layer on their exoskeletons with silica. Without this layer, the insects lose moisture rapidly, leading to dehydration and death.
Dr. Killigan's Dust to Dust is a safer and more effective alternative to diatomaceous earth for insect control, with proven kill times up to 50% faster.
Cabbage loopers
Quick identification: Fully-grown cabbage loopers are one-and-a-half inches long, yellowish-green with whitish stripes and have arch-like movements like an inchworm.
Plants they feed on: These predatory insects target a variety of garden vegetables, with a preference for:
- Cabbage
- Broccoli
- Cauliflower
- Kale
They’ll also feed on other garden vegetables when their favorites aren’t available.
Damage they cause: Cabbage loopers leave large, jagged holes in the lower half of entire plants and other vegetable crops.
How to get rid of this pest: If cabbage loopers persist into fall and garden debris isn’t cleared, they can overwinter and return next season. For small infestations, treat the tops and bottoms of leaves with Dust to Dust using the Insect Buster. Apply in the late evening or early morning, when bees and beneficial insects are less active.
For an alternative, neem oil is a natural solution that disrupts the cabbage looper’s life cycle. It works as both an insecticide and repellent, preventing larvae from maturing and deterring adults from laying eggs. To use, mix neem oil with water and a mild soap (as directed on the label) and spray directly onto infested leaves. Reapply after heavy rains or every 7-10 days for best results.
Quick fact: Fall is a great time to grow cabbage—a great winter garden plant that can withstand cold temperatures and improves in flavor after exposure to light frosts.
Colorado potato beetle
Quick identification: Found throughout the United States, these beetles are about one-half inch in length and have a bright yellowish-orangish oval body with bold black stripes. Their larvae are the same length, but are hump-backed, a shiny reddish bronze color and have two distinctive rows of black spots on each side.
Plants they feed on: Colorado potato beetles are a serious fall pest, primarily targeting plants in the Solanaceae family and causing significant defoliation. Their most common hosts include:
- Potatoes (their preferred host)
- Eggplants
- Tomatoes
- Peppers
Damage they cause: The larvae will often strike new foliage tips first, then target whole leaves and entire plants. After Colorado potato beetles have had their heyday, only the skeletal, veiny remains of withered up plant-frames are left.
How to get rid of this pest: Immediate action is key. If swift action is not taken, two to three generations—in egg, larvae and adult stages—can be present in your garden: an uncontrollable situation.
Start by using the Insect Buster to apply Dust to Dust to the undersides of leaves. As the beetles walk across the powder, it scuffs their exoskeletons, leading to dehydration and death. For a hands-on approach, manually remove adult beetles and drop them into a bucket of soapy water to eliminate them quickly. For an organic alternative, neem oil disrupts the beetles' feeding and reproductive cycles. Spray it directly on leaves—both the tops and undersides—focusing on areas where beetles and larvae are active. Reapply after rain or heavy watering to ensure continued protection.
Cucumber beetles
Quick identification: There are spotted and striped cucumber beetles, both of which are one-fourth inch long with black heads and long, slender antennae. The difference is that the spotted variation has 12 black spots on its greenish-yellow abdomen, whereas the striped variation has three black stripes running down its yellowish-orange abdomen.
Plants they feed on: Cucumber beetles primarily target cucurbit plants but can also damage other crops and flowering plants. Key hosts include:
- Cucumbers
- Squash
- Pumpkins
- Melons (e.g., cantaloupe, watermelon)
- Beans
- Corn
- Potatoes
- Tomatoes
- Flowering plants (e.g., roses, zinnias)
Damage they cause: As larvae, they will feed on the roots of these plants, which makes their presence difficult to detect. As adults, they feed on plant tissue, foliage, stems, flowers and fruit. Evidence of their damage is either holes in leaves or yellowing and wilting leaves. In fruit, they will create unattractive scars and pockmarks.
Quick fact: They transmit bacterial wilt, a devastating fatal disease for your garden plants (in the cucurbit family).
How to get rid of this pest: Act quickly—cucumber beetles can multiply fast, wreaking havoc on cucurbit plants. Apply Dust to Dust with the Insect Buster, focusing on the undersides of leaves where beetles and larvae hide.. For quick control, hand-pick adults and drop them into soapy water.
To prevent future infestations, use floating row covers to block adult beetles from reaching plants. Be sure to remove the covers when plants bloom to allow pollination. If you prefer an organic approach, spray neem oil on affected leaves, reapplying after rain or heavy watering for ongoing protection.
Cutworms
Quick identification: Cutworms are smooth, have dark-colored bodies—ranging from brown to pinkish or green, gray or blackish—and are about two inches when fully grown. They typically curl into a tight C-shape when disturbed.
Plants they feed on: Cutworms aren’t picky eaters, but plants with soft or weakened stems are particularly at risk. These sneaky pests attack from the undersides, staying hidden until the damage is done. Common targets include:
- Cabbage
- Tomatoes
- Peppers
- Peas
- Asparagus
- Beans
- Carrots
- Celery
- Corn
- Lettuce
- Potatoes
Damage they cause: Cutworms quickly ‘cut’ down the plants on which they feed, chewing them through near their stems. They have no mercy for young rising-to-new-heights plants and will take their lives at the base (or near the ground level). Some may even climb up the plants to feed on the foliage, leaving ragged holes in their leaves. If you find a wilted plant, the culprit may be a cutworm that simply didn’t chew all the way through.
How to get rid of this pest: To effectively eliminate cutworms, combine multiple strategies for maximum control. Start by using the Insect Buster to apply Dust to Dust around the base of plants and along the soil surface, creating a protective shield that dehydrates the larvae as they crawl across it. Release beneficial nematodes into the soil, where these microscopic predators will target and eliminate cutworm larvae naturally. For added protection, place plant collars made of cardboard, plastic or aluminum foil around the base of young plants to physically block cutworms from reaching and chewing through the stems.
Quick fact: Cutworms overwinter as larvae in your soil, so tilling your garden in the fall and spring can also help reduce carryover.
