5 bad bugs in your garden this fall

5 bad bugs in your garden this fall

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, fresh scent. The dirt had wedged its way beneath my fingernails, painted the beige cuffs of my sleeves various 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 seemed to harbor 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.

What plant pests will overwinter in my garden?

There are five key types of insects that will do their very best to overwinter in your garden. Though a delightful thought for the insect, it can mean death and destruction for your garden. Proper plant pest identification is essential. These insects are aphids, cabbage loopers, Colorado potato beetles, cucumber beetles, and cutworms.

There are other pests that will attempt to overwinter in your home. These little miscreants, the ones that endeavor to go indoors—in your house—in the winter, must be dealt with, too. You must also protect your home.

What do these bad garden bugs look like (and what else do I need to know)? 

In this article, we’ll give you the keys needed to understand the sometimes hidden mysteries of what may be happening to your garden plants. It’s important to know the following:

  • What do these pests look like? Without proper identification, there cannot be proper treatment. 
  • Which plants need to be protected from these gluttonous leaf-eating pests? Each pest has a select few favorite plants that they will voraciously attack and eat. 
  • What harm do these pests cause to these plants? Will the leaves just wither or will the plant keel over and die?   
  • What are the best ways of getting rid of these mischievous pests? It’s necessary to get rid of these bugs that are eating your plants before they attempt to get rid of you (or at least your presence among their once-green leaves).

What are the five bad bugs on my garden plants?

1. Aphids

Quick identification: Aphids are small, pear-shaped, soft-bodied insects. Various species can appear white, black, brown, gray, yellow, light green, or even pink. Some may have a waxy or wooly coating. The nymphs (young aphids) look similar to the adults.

Plants they feed on: If you’re seeing small white bugs on your squash plants, make sure to thoroughly check your other plants too. Common aphids target a wide variety of plants, including fruit trees, melons, vine-grown vegetables, underground vegetables, leafy vegetables, house plants, and even some herbs, as these all produce plant sap. Well-known examples include cucumber, pumpkin, melon, bean, potato, lettuce, beet, chard, and bok choy.

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 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, a superb alternative to diatomaceous earth. Reapply after heavy rains.

You can consistently get rid of bugs on plants with Dust to Dust, as it employs silica to break down the delicate wax layer that covers insects' exoskeletons. This wax coating is critical for these bugs as it helps prevent the loss of water from their bodies through the exoskeleton. The breakdown of this layer caused by silica ultimately leads to the insects' death through dehydration.

Dr. Killigan's Dust to Dust Non-Toxic Insect Powder is a safer and more effective alternative to diatomaceous earth for insect control. Dust to Dust is proven to have kill times up to 50% faster than diatomaceous earth.

2. Cabbage loopers

Quick identification: Fully-grown cabbage loopers are one-and-a-half inches long, a yellow-green color with whitish stripes, and have arch-like movements like an inchworm.

Plants they feed on: These predatory insects are the most common pest for cabbage, broccoli, cauliflower, and kale, but will eat other garden vegetables as well.

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 unable to remove this green plant bug before fall and if you don’t clear out your garden from plant debris, the cabbage looper may carry over into the next season. For a small infestation, you can stop cabbage worms from eating plant leaves by treating the tops and bottoms of these leaves with Dust to Dust, or diatomaceous earth, with the use of the Insect Buster. I recommend applying it only during the late evening or early morning and when plants are not blooming, as this is when bees and other beneficial insects are typically out foraging. Another alternative solution is neem oil. 

Quick fact: Fall is a great time to grow cabbage, a great winter garden plant that can not only withstand cold temperatures, but also improve in flavor after exposure to light frosts.

3. Colorado potato beetle

Quick identification: Colorado potato Beetles, found throughout the United States, are about ½ 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: These ferocious beetles are considered a serious fall pest, damaging not only your potatoes, but also attempting destruction to your tomatoes and eggplants too.


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 hay day, only the skeletal, veiny remains of withered up plant-frames are left.

How to get rid of this pest: Immediate addressal 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. Use a strong spray combination of pest repelling and eliminating techniques. I recommend the use of the Insect Buster as a Dust to Dust, or diatomaceous earth, application. Use it to dust the undersides of the plant’s leaves with this powder, which, as the beetles walk through it, will cause a scuffing in their joints, ultimately leading to their death. In combination with the Insect Buster, manually pick off any adult beetles, and dispose them in soapy water.

4. Cucumber beetles

Quick identification: There are both spotted and striped cucumber beetles, both of which are ¼ inch long, and have 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 favor cucurbit plants, which consist of melons, gourds, squash and cucumbers.


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: To get rid of cucumber beetles, use the Insect Buster and disperse Dust to Dust, or diatomaceous earth, on your infected plants and the ground around them. Focus on the ground around the plants and apply either in the evening and early morning, as noted above, so as not to disturb beneficial pollinating insects, like bees. Do not spray your flowering plants.

5. 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: Plants with soft or weakened stems are particularly at risk, though cutworms are not picky eaters. They will happily terrorize cabbage, tomatoes, peppers, and peas, going after their undersides, (where this sneaky pest stays out of sight until the damage is done). They will also threaten the lives of asparagus, beans, carrots, celery, corn, lettuce, and 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 get rid of cutworms, use the Insect Buster, which eliminates waste by using a precise distribution method, and disperse Dust to Dust, or diatomaceous earth, as a protective shield around your plants. You may also release beneficial nematodes into the soil to help control these pests. If cutworm larvae are left in your garden this fall, they will surely carry over into the next year.

Quick fact: Cutworms overwinter as larvae in your soil, so tilling your garden in the fall and spring can also help reduce carryover.

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