While worms can often play a beneficial role in soil health by aiding in decomposition and improving soil structure, not all worms are helpful for your garden.
Some worms can actually damage plants and decrease soil fertility. This article will introduce you to 12 types of detrimental worms that might inhabit your garden soil and provide effective methods for their removal.
Cutworms are moth larvae that can cause significant damage to plants by cutting off seedlings at the soil line. These pests are most active at night.
You can physically remove cutworms by hand or use biological control methods like the introduction of beneficial nematodes or Bacillus thuringiensis (Bt), a soil-dwelling bacterium that cleans certain insects.
Armyworms, like cutworms, are moth larvae. They’re called “army” worms because they move in large groups, consuming most vegetation in their path.
Natural predators such as birds, parasitic wasps, and certain beetles can keep armyworm populations in check. For more serious infestations, using Bt or insecticides designed specifically for these pests may be necessary.
Wireworms are the larvae of click beetles. They are particularly harmful to root crops, like potatoes and carrots, and cereal crops.
Crop rotation and using specific pesticides designed for wireworms can help manage their populations.
4. Root Maggot Worms:
Root maggots are small, white, legless larvae that cause damage to plant roots, inhibiting their growth and potentially causing plant to dry away.
Use floating row covers to prevent adult flies from laying eggs near your plants. Beneficial nematodes and rove beetles can also help control root maggot populations.
5. Grub Worms:
Grub worms, or beetle larvae, feed on organic matter and plant roots, causing noticeable damage to lawns and gardens.
Beneficial nematodes, milky spore bacteria, or specific grub pesticides can be used to control grub worms.
6. Cabbage Worms:
Cabbage worms are the larvae of the cabbage white butterfly and feed extensively on brassicas, like cabbage and broccoli.
Hand-picking, introducing natural predators like birds and wasps, or using Bt can control cabbage worm populations.
7. Corn Earworms:
Corn earworms are moth larvae that infest a wide range of crops but are particularly problematic for corn.
Use a combination of crop rotation, beneficial insects, and targeted insecticides to manage corn earworm populations.
8. Leafminer Worms:
Leafminer worms are larvae of various insects that create distinctive trails or “mines” in leaves, impacting plant health.
Introduce beneficial insects, such as parasitic wasps, or apply neem oil to affected plants.
9. Tomato Hornworms:
These are large, green caterpillars that can cause extensive damage to tomato plants and other members of the nightshade family.
Hand-picking, introducing parasitic wasps, or applying Bt are effective methods for controlling tomato hornworms.
10. Cabbage Looper:
Cabbage loopers are moth larvae that feed on a wide range of plants, including many common vegetables and flowers.
Introducing natural predators, hand-picking, or using Bt can help manage cabbage looper populations.
11. Vine Weevil Larvae:
Vine weevil larvae feed on plant roots, leading to wilting and potential harm to plants.
Introducing beneficial nematodes or using specific insecticides can control vine weevil larvae.
12. Codling Moth Larvae:
Codling moth larvae are major pests of apple, pear, and walnut trees.
Use pheromone traps to catch adult moths and prevent them from laying eggs. Application of Bt or insecticides may be necessary for severe infestations.
Garden worms, while often beneficial, can sometimes pose significant challenges for the diligent gardener. By understanding the types of harmful worms that can inhabit your soil and how to effectively manage or remove them, you can ensure that your garden stays healthy, vibrant, and productive.