These are some of the pests that I have encountered in my garden. I’m sharing pictures and information with you about each to help you identify, prevent and, if in large numbers, get rid of the majority in order to keep your garden thriving.
Pests of the Nightshade Family
I found this pest on one of my tomato plants and, at first glance, thought it was a tomato hornworm. After an Instagram gardener commented, I researched further and found out that the red horn distinguishes it as a tobacco hornworm, more commonly found in the southern US.
Plants That Tobacco and Tomato Hornworms Attack
Since both tobacco and tomatoes are part of the Nightshade, or Solanaceae, family, both Tobacco Hornworms and Tomato Hornworms are pests of this family of plants.
How to Prevent Tomato Hornworms
An important note is that the only year I have found this crazy looking caterpillar on my tomato plants was the year I grew them without their allies basil and marigold nearby.
I suggest growing basil at the base of your tomato plants as a way to prevent both Tobacco and Tomato Hornworms, because, in addition to my personal experience, a study conducted by Iowa State University confirms that it lessens the insect damage to tomato plants.
How to Get Rid of Tobacco Hornworms
After spotting the caterpillars, remove them from your plants immediately. They can eat a significant amount of foliage in a very short amount of time.
Despite their wild look, they actually will not harm you. I hesitated to pick the caterpillar above off my tomato plant when I first saw it because the horn looks a bit intimidating. After a quick search, I was relieved to discover that they are harmless to humans and the horn can’t sting us.
Pests of the Cucurbit Family
One spring we were surprised to find a few pumpkin plants growing out of our compost – we always welcome free food! The plants were super healthy and we were finding pumpkins all over our yard the whole summer as the plants vined out more and more. I let the plants continue to grow into the fall, despite some rough looking foliage, because they were still producing pumpkins. That was a mistake…
Plants That Squash Bugs Attack
Squash bugs attack…you guessed it…winter and summer squash plants. They also attack their family members, including gourds, melons, cucumbers and pumpkins.
How to Prevent Squash Bugs
The year I let our pumpkin plants grow from early spring to late fall was when I learned to not let plants stick around too long, especially if they aren’t doing well. They become more susceptible to pests, and before I knew it, I was battling what felt like an entire army of squash bugs.
How to Get Rid of Squash Bugs
The best method I found was handpicking (or shovel scooping) them off the plants and out of the mulch, and then sealing them in a plastic Ziploc bag that I ultimately threw in the trash can. There is a mix of the larvae and adults in the image above.
Pests of the Brassica Family
Upon first glance, these small white butterfly looking moths are a beautiful addition to your garden. But once you know who they are and what they are doing, their beauty quickly fades. They lay eggs on Brassicas and their larvae, the cabbageworms, devour your plants.
Plants That Imported Cabbageworms Attack
The adult imported cabbageworms lay eggs on Brassica family members in the garden. When the eggs hatch, they can devour all the foliage, leaving only the stems and large veins.
How to Prevent Imported Cabbageworms
Use tulle or row cover to protect your plants from the moths laying their eggs on the leaves – just be sure there aren’t any openings for the moths to get inside the cover.
I have had tremendous success covering my plants with inexpensive tulle from a nearby fabric store. Since plants in the Brassica family don’t need to be pollinated, you can keep them covered all season long.
How to Get Rid of Imported Cabbageworms
Check the underside of your Brassica leaves for eggs. They are white at first and soon turn a yellowish color. As shown in the image above, the eggs are spread out on the leaves and stick out from them with a slight point at the end, which faces away from the leaves.
Remove the eggs from the leaves by smooshing them in between your fingers while wearing garden gloves, or blast them with a strong spray of water.
In addition to checking the underside of the leaves for eggs, handpick the green caterpillars off your plants. I give mine to my chickens for a tasty treat, but you could also remove and dispose of them.
Pests That Attack Multiple Plant Families
These pests are among the easiest to identify due to the unique mining pattern on the leaves. The larvae tunnel through the leaves, leaving a squiggly, white line or blotchy mark.
The adult stage can be a variety of insects – flies, beetles and moths.
Plants That Leafminers Attack
There are several species of leafminers, and they feed on a large variety of crops such as spinach, kale, peppers, tomatoes, pumpkins, squash and okra plants.
How to Prevent Leafminers
They typically do not cause enough damage to take preventative action other than the basic plan of maintaining healthy soil, attracting beneficial insects and rotating crops.
Parasitic wasps, in particular, are predators of leafminers, if you want to attract them to your growing space.
How to Get Rid of Leafminers
When you see the appearance of one or multiple squiggly, white lines on your leaves, prune off all infected leaves, smoosh them in your hand and dispose of them in the trash.
Continue checking and removing leaves, when applicable, throughout the season, as some eggs may have been overlooked when you pruned the leaves.
You will know flea beetles are present in your garden once you see the damage on your foliage. The bites are small and go through the entire leaf. Below is an eggplant leaf with flea beetle damage.
Plants That Flea Beetles Attack
They feed on a large variety of crops such as lettuce, potatoes, eggplant, squash and bean plants.
How to Prevent Flea Beetles
If you are starting seeds outdoors, you can use a row cover to protect plants until they reach maturity, becoming stronger and less likely to suffer from damage done by flea beetles.
If you are transplanting starts you purchased or starts from seeds you started indoors, typically they will be mature enough that you don’t need to take action.
How to Get Rid of Flea Beetles
If your plants are mature when the flea beetles arrive, they will most likely not cause enough damage to ruin your crop. My mature eggplant was super prolific regardless of all of the bites (see the leaf above). However, one fall, we lost our eggplant plants due to all the flea beetle damage done in the early stages of the plant’s life. If your plant is mature, I suggest letting nature work for you and not worrying about the damage.
If your plants are immature when the bites start to appear (less than 5 or so leaves), it may be best to remove the infected plants from your garden. If you don’t want to do so, another option for the home gardener is to plant a trap crop. The University of Minnesota Extension office recommends growing radish as a trap crop for flea beetles.
General Tips for Pest Management
Check out my top three tips on how to manage pests in an organic garden for general management that isn’t specific to any one pest.
I hope this helps you identify pests, damage or both in your garden and make an informed decision on what’s best for you and your growing space.