A good amount of insect life is very beneficial in a garden. Earthworms help cultivate and provide nutrients to soil and bees pollinate. Soil should contain a good amount of beneficial life. (See this article for desired amounts of insect life). However, any garden can also be raided by unwanted pests.
Checking over the garden on the regular is so important. Finding and identifying unwanted pests is pertinent to saving a garden from infestation and destruction. If you believe your garden is experiencing an insect issue, this list will be helpful in identifying insects and their damage, as well as providing solutions to eliminating the unwanted insects.
I will prevent pests from devouring your crops, and the vines in your fields will not drop their fruit before it is ripe,” says the LORD Almighty.
Malachi 3:11
1. Aphid
What is it? An aphid is a very tiny (less than 1/10 inch long) soft-bodied bug that is shaped like a pear. They can appear any color from pale green, brown, black, yellow, pink or blue.
When do they appear? They lay their eggs in the Winter and hatch in early Spring.
What plants are most vulnerable? Aphids can affect almost any plant – vegetable, fruit or flower.
What damage can they cause? They are known for sucking sap from leaves, fruit or stems, which causes foliage to yellow and become weak, attracting ants, and their excrement attracts mold.
How can they be eliminated? To get rid of aphids, spray neem oil directly on the plants. Neem oil is safe and will not kill off beneficial insects. Other options are to spray plants with soapy water or use a sticky trap.
How can they be avoided? Neem oil can also be sprayed on plants to avoid aphids. Other options are to use a row cover or the aluminum foil trick (place a square of foil under the plants to reflect and confuse insects). Ladybugs, spiders, syrphid flies, and lacewings help control the aphid population. To attract these insects in order to keep aphids away, plant plants in the clover, alyssum, aster or parsley families. Onions and garlic may also keep aphids away from the garden.
2. Asparagus Beetle
What is it? An asparagus beetle is a quarter-inch long oblong insect, typically bluish black in color with white spots on its back and reddish-orange markings.
When do they appear? Asparagus beetles over-winter (hide) in the garden and come out in the Spring.
What plants are most vulnerable? Asparagus.
What damage can they cause? They chew leaves and spear tips of asparagus.
How can they be eliminated? To get rid of these bugs, shake beetles and dark brown eggs (usually found on spears) from plants and drop them into soapy water.
How can they be avoided? Be sure to remove all affected plants and their debris from the garden after harvest. To prevent these beetles from returning, neem oil can be sprayed on plants at the beginning of the season. Use row covers for added protection. Ladybugs and predatory flies can help keep asparagus beetles away. They do not like tomatoes, nasturtiums or calendula, so use these plants as tools to drive asparagus beetles away.
3. Blister Beetle
What is it? They are a ¾ inch long, slim insect with long legs and a narrow neck. They are typically either a metallic blue-gray, black or black and yellow striped insect.
When do they arrive? Blister beetles over-winter in the garden and then the adults appear in early to mid-summer.
What plants are most vulnerable? Basically any vegetable plant is susceptible to blister beetles. The adults feed on leaves, blossoms and fruits of almost any vegetable plant.
What damage can they cause? These bugs chew leaves, blossoms and fruits of vegetable plants. They also secrete a harmful oil that can cause blisters on skin, so be sure to wear gloves when coming in contact with these insects. Blister beetles are toxic to some animals.
How can they be eliminated? Remove these bugs by hand or by shaking them out of plants and drop them into soapy water. Remember to wear gloves because of the harmful, blister-causing oil they can secrete! Spray neem oil directly on the plants. Neem oil is safe and will not kill off beneficial insects
How can they be avoided? Be sure to remove all affected plants and their debris from the garden after harvest. Use neem oil. Use row covers for protection. Keep a close eye on the garden – especially the edges – to avoid infestation. Ladybugs and predatory flies can help keep these beetles away. They do not like nasturtiums or calendula, so use these plants as tools to drive blister beetles out of the garden.
4. Cabbage Looper
What is it? A cabbage looper is caterpillar that is light green in color with black markings and two yellow stripes on its back. It loops when it crawls. As an adult, it is a brown moth.
When do they arrive? These caterpillars are most prevalent in Spring.
What plants are most vulnerable? They like cabbage, brussel sprouts, collards, cauliflower, potatoes, tomatoes, beans, peas and other green leafy vegetables.
What damage can they cause? They are known to eat holes in leaves. They may also eat seedlings.
How can they be eliminated? Sprinkle caterpillars with flour or salt. Spray neem oil directly on the plants. Neem oil is safe and will not kill off beneficial insects. Trichogramma wasps, lacewing and ladybugs may also help get rid of them.
How can they be avoided? Spray area with neem oil. Use a row cover to prevent moths from laying eggs in the soil. Plant resistant varieties when available. Plant marigolds around the garden to keep these bugs away. They are also repelled by garlic, hot peppers, hyssop, onions, rosemary, sage, tansy, and thyme, so plant these varieties to avoid cabbage loopers in the future.
5. Cabbage Maggot
What is it? A cabbage maggot is a small worm-like creature with a flat end. It is typically grayish-white in color and about ⅓ inch long. An adult looks like a typical housefly.
When do they arrive? They are most prevalent in early-spring to fall.
What plants are most vulnerable? They like cabbage, brussel sprouts, collards, cauliflower, turnips, parsnips and radishes.
What damage can they cause? They are known to create tunnels in stems just below the surface of the soil. The plants may wilt and die.
How can they be eliminated? To get rid of cabbage maggots, apply lime or wood ashes around the base of plants. Beneficial nematodes, chalcid wasps and
How can they be avoided? Cabbage maggots are repelled by tomatoes, mint, sage, and rosemary.
6. Carrot Rust Fly
What is it? A carrot rust fly is typically black in color with a yellow head and legs. It grows to about ⅕ inch long. As maggots, they are about ⅓ inch long and may be yellow, white or a mix of the two colors.
When do they arrive? They typically over-winter as maggots and are visible in the spring.
What plants are most vulnerable? Celery, carrots, parsnips and parsley are most vulnerable to carrot rust flies.
What damage can they cause? Maggots of this fly tunnel into roots. This can cause stunted growth or soft rot of the plants.
How can they be eliminated? Apply wood ashes to the tops of plants to get rid of these bugs. Also, remember to rotate crops! Parasitic nematodes can also be helpful.
How can they be avoided? Some plants that carrot rust flies do not enjoy are onions, leeks, rosemary, sage, wormwood, pennyroyal, and salsify.
7. Colorado Potato Beetle
What is it? A Colorado potato beetle is a yellow beetle with a rounded back. It is orange with black markings (usually stripe-like) and about ⅓ inch long. The immature form of this beetle (grub) is typically red with a black head and black spots.
When do they arrive? They usually emerge in the Spring.
What plants are most vulnerable? Colorado potato beetles typically attack potatoes, tomatoes, peppers and eggplants.
What damage can they cause? They are known to skeletonize leaves (eat all tissue except for veins) and chew on tips of growth.
How can they be eliminated? Pick beetles, larvae and eggs off plants by hand. Be sure to check tops and bottoms of leaves. Spray neem oil directly on the plants. Neem oil is safe and will not kill off beneficial insects. Mix basil leaves with water and spray on plants. Ladybugs or bacteria called Bacillus thuringiensis can also be helpful.
How can they be avoided? To avoid these beetles, place mulch or hay around plants so that beetles cannot reach the stems. Use neem oil. Row covers are another option. Plant basil, tansy or coriander to keep them away.
8. Corn Earworm
What is it? A corn earworm is a white, green or red spiny caterpillar that is about an inch and a half long. The adult is a brown moth.
When do they arrive? Gardeners typically see corn earworms in late spring.
What plants are most vulnerable? Corn.
What damage can they cause? On early plants, they eat buds and leaves. On more mature plants, they eat silks and corn kernels at the tip of the ear of corn.
How can they be eliminated? Remove the earworms from the husks after the silks brown. Spray neem oil directly on the plants. Neem oil is safe and will not kill off beneficial insects. Remove all plants and debris after harvesting. Beneficial nematodes, Bacillus
How can they be avoided? Spray corn plants with neem oil to prevent corn earworms from attacking plants.
9. Cutworm
What is it? A cutworm is generally a rather plump, two inch long caterpillar that is gray or brown in color. It will curl up when disrupted.
When do they arrive? They typically can be seen in early spring and throughout growing season.
What plants are most vulnerable? Many plants are vulnerable to cutworms including broccoli, beans, cabbage, tomatoes, potatoes, lettuce, kohlrabi, corn, peppers, cauliflower, brussel sprouts, radishes, rutabaga, turnips and collards.
What damage can they cause? Cutworms are known to eat through almost anything on a plant. They will eat the stem just below the surface of the soil, roots, leaves, buds and fruit.
How can they be eliminated? Spray neem oil directly on the plants. Neem oil is safe and will not kill off beneficial insects. Beneficial nematodes, Bacillus thuringiensis, tachinid flies and braconid wasps will also help eliminate cutworms.
How can they be avoided? Clear garden of weeds and other debris to discourage them from laying eggs. Use neem oil. Sprinkle wood ash around plants.
10. Earwig
What is it? Earwigs are leathery, worm-looking creatures that are about ¾ inch long with pincers on its end. They are reddish-brown in color and typically can be seen at night.
When do they arrive? Earwigs are most visible in late spring.
What plants are most vulnerable? Almost any garden vegetable or flowers are vulnerable to earwigs.
What damage can they cause? Earwigs are typically only a problem if many of them are present. They eat leaves, flower petals and soft fruit and leave ragged holes where they chew.
How can they be eliminated? Take old newspaper or cardboard, wet it and roll it up. These can be used to trap earwigs. Tachinid flies can help keep earwigs away
11. European Corn Borer
What is it? A European corn borer is a one-inch-long, flesh colored caterpillar with a dark colored head and small brown spots. The adult is a moth with a zig-zag pattern on its wings.
When do they arrive? Caterpillars can be seen in the spring and moths emerge in early summer.
What plants are most vulnerable? The most vulnerable plants are corn, peppers, tomatoes, potatoes and chard.
What damage can they cause? Young insects chew on leaves and tassels, while older insects dig into stalks of plants.
How can they be eliminated? Spray neem oil directly on the plants. Neem oil is safe and will not kill off beneficial insects. Pick caterpillars off plants by hand. Ladybugs, braconid wasps, tachinid flies and Bacillus thuringiensis can also be beneficial in eliminating European corn borers.
How can they be avoided? Use neem oil. Keep the garden free of weeds and plant debris.
12. Flea Beetle
What is it? A flea beetle is a tiny (⅛ inch long) black, brown or bronze beetle that can jump similar to a flea. They also have large back legs.
When do they arrive? They over-winter in the garden and then come out in the spring.
What plants are most vulnerable? The most common plants for flea beetles to disturb are beans, beets, broccoli, Brussels sprouts, cabbage, cauliflower, chard, collards, corn, eggplants, kohlrabi, muskmelons, peppers, potatoes, radishes, spinach, tomatoes, turnips, watermelons.
What damage can they cause? Flea beetles are known for chewing tiny holes in leaves, which causes plants to wilt and experience stunted growth.
How can they be eliminated? Spray neem oil directly on the plants. Neem oil is safe and will not kill off beneficial insects. Beneficial nematodes can also help get rid of flea beetles.
How can they be avoided?
13. Harlequin Bug
What is it? A Harlequin bug is about ¼ inch long and shaped like a shield. It is typically shiny looking, red and black with large triangles on its back.
When do they arrive? They over-winter in debris and then show up in the spring.
What plants are most vulnerable? Brussels sprouts, cabbage, cauliflower, collards, kohlrabi, mustard, radishes and turnips are most vulnerable.
What damage can they cause? These bugs suck the sap from plants, which causes wilting, blotchy leaves and can even kill plants.
How can they be eliminated? Remove bugs and any debris in garden by hand. Sparrows and mockingbirds will help control the harlequin bug population.
How can they be avoided? Keep the garden clean and use compost.
14. Hornworm
What is it? A hornworm is a green caterpillar with white stripes. It is about three to five inches long with a horn on its backside. The adult is a large brown moth with orange spots.
When do they arrive? Caterpillars over-winter in soil and the moths come out in late spring and early summer.
What plants are most vulnerable? The plants that are most susceptible are tomatoes, peppers, potatoes, eggplant and dill.
What damage can they cause? Hornworms are known for chewing leaves and fruits.
How can they be eliminated? Spray neem oil directly on the plants. Neem oil is safe and will not kill off beneficial insects. Sprinkle dried hot peppers on plants. Bacillus
15. Japanese Beetle
What is it? A Japanese beetle is a blue-green metallic beetle with bronze wing covers. It is typically about ½ inch long. The grub is a gray-brown color with a brown head.
When do they arrive? Japanese beetles over-winter under the ground and then emerge in the early summer.
What plants are most vulnerable? The most susceptible plants are asparagus, beans, okra, peaches, raspberries, rhubarb and corn.
What damage can they cause? Grubs eat roots of grass and adults eat leaves and flowers.
How can they be eliminated? Remove beetles by hand and clean garden of debris. Spray neem oil directly on the plants. Neem oil is safe and will not kill off beneficial insects. Grubs do not like high soil pH.
How can they be avoided? Use neem oil. Larkspur foliage is toxic to beetles. Geraniums and smartweed repel Japanese beetles.
16. Leaf Hopper
What is it? A leafhopper is a bug with wedge-shaped wings that moves sideways. It is about ⅓ inch long and green, brown or yellow in color.
When do they arrive? Spring.
What plants are most vulnerable? The most vulnerable plants are potatoes, beans, carrots, celery, chard, eggplant, rhubarb, beets, lettuce, spinach, squash and roses.
What damage can they cause? Leafhoppers suck the juice from stems and leaves of plants, which results in curled leaves and stunted growth. Some leafhoppers can transmit viruses.
How can they be eliminated? Spray neem oil directly on the plants. Neem oil is safe and will not kill off beneficial insects. Use row covers on plants because leafhoppers prefer open areas. Green lacewing, braconid wasps and trichogramma wasps can help get rid of leafhoppers.
How can they be avoided? Use neem oil.
17. Leaf Miner
What is it? Leaf miners are about 1/10 of an inch long, black flies with yellow stripes. The larvae are pale green maggots.
When do they arrive? Adult leaf miners come out in spring.
What plants are most vulnerable? The plants leaf miners bother the most are beans, beets, cabbage, chard, lettuce, peppers and tomatoes.
What damage can they cause? Leaf miner larvae dig canals inside leaves, which stunts plant growth.
How can they be eliminated? Remove and destroy any affected leaves. Spray neem oil directly on the plants. Neem oil is safe and will not kill off beneficial insects. Use row covers. Chickadees, finches
18. Mexican Bean Beetle
What is it? Mexican bean beetles have a similar look to ladybugs. They are a yellow or copper color with sixteen black dots in three rows on their backs.
When do they arrive? Adults can be seen mostly in the spring.
What plants are most vulnerable? Beans and squash are the most vulnerable plants to mexican bean beetles.
What damage can they cause? These beetles are known to skeletonize leaves (eat all tissue except for veins), which can cause plants to dry out and die. They may also eat bean pods and stems.
How can they be eliminated? Remove eggs and beetles by hand. Spray neem oil directly on the plants. Neem oil is safe and will not kill off beneficial insects. Remove all plant debris to discourage egg-laying. Ladybugs and pediobius wasps can help control population.
How can they be avoided? Use neem oil. Plant nasturtiums, marigolds, savory and/or garlic nearby.
19. Onion Maggot
What is it? These maggots are about ⅓ inch long, brown and hairy with no legs.
When do they arrive? Adult flies are most prevalent in late spring when they lay eggs at the base of plants.
What plants are most vulnerable? Onions and radishes are most vulnerable.
What damage can they cause? Onion maggots tunnel into stem of onions near the bulb.
How can they be eliminated? Remove and destroy infected plants. Use wood ash as barrier. Beneficial nematodes, predatory flies and ichneumonid wasps can also help get rid of onion maggots.
How can they be avoided? Do not plant plants too close together. Keep garden free of debris and weeds.
20. Slug
What is it? A slug is a mollusk that is either white, gray, brown, yellow or even purple. They are typically about two inches long.
When do they arrive? Slugs prefer cooler temperatures. They typically arrive in early spring.
What plants are most vulnerable? Almost any vegetable is vulnerable to slugs.
What damage can they cause? Slugs are known to eat large holes in leaves, stems and fruit.
How can they be eliminated? Remove slugs by hand an sprinkle slugs with salt to destroy. Place sand, lime or ash around plants to act as protective borders. Spray neem oil directly on the plants. Neem oil is safe and will not kill off beneficial insects. Place saucers of stale beer at soil level to trap slugs. Garden birds, woodpeckers, robins, snakes, toads, turtles, centipedes and certain types of beetles can help eliminate slugs.
How can they be avoided? Use neem oil. Mulch around plants.
21. Spider Mite
What is it? A spider mite is a red, black or brown spider-like mite.
When do they arrive? Spider mites love dry and hot weather.
What plants are most vulnerable? Spider mites can attack any fruit or vegetable plant.
What damage can they cause? They are known for sucking juices from plants causing yellow and dry leaves. They are often found on the underside of leaves.
How can they be eliminated? Spray neem oil directly on the plants. Neem oil is safe and will not kill off beneficial insects. Try spraying either a soapy water solution or a solution of wheat flour, buttermilk and water on leaves. Ladybugs, lacewings and predatory mites can also help eliminate spider mites.
How can they be avoided? Use above methods as prevention.
22. Squash Bug
What is it? Squash bugs are shaped like shields with flat backs. They are typically brown, about ⅝ inch long with triangle markings on their backs.
When do they arrive? When vines begin to grow, squash bugs begin to emerge.
What plants are most vulnerable? Obviously, squash is susceptible, but squash bugs may also attack any vine crops such as cucumbers, watermelons, muskmelons,
What damage can they cause? Not only do these bugs suck plant juices, but they also inject toxins into the plants. This causes the plants to wilt and die.
How can they be eliminated? Remove bugs, weeds and debris from garden. Spray neem oil directly on the plants. Neem oil is safe and will not kill off beneficial insects. Use row covers. Tachinid flies may also help eliminate squash bugs.
How can they be avoided? Use above methods as prevention.
23. Squash Vine Borer
What is it? A squash vine borer is a fat, white caterpillar with a brown head. The adult version is a moth with red, white and copper markings that looks similar to a wasp.
When do they arrive? They most often show up in late spring.
What plants are most vulnerable? The most susceptible plants are vine crops, which include cucumbers, pumpkins, watermelons, muskmelons and squash.
What damage can they cause? They typically chew holes in stems, which can cause wilting.
How can they be eliminated? Remove caterpillars by hand and keep garden free of debris and weeds. Use nylon stockings around stems to discourage egg-laying. Destroy entire infected crop and replant for a later crop. Use row covers. Plant resistant varieties when possible. Trichogramma wasps can aid in getting rid of squash vine borers.
How can they be avoided? Use row covers and other above methods for prevention.
24. Striped Cucumber Beetle
What is it? A striped cucumber beetle is a yellow beetle with black stripes that is about ¼ inch long. The larvae are skinny and white.
When do they arrive? They typically show up in late spring.
What plants are most vulnerable? The most vulnerable plants are vine plants, as well as corn, peas, beans,
What damage can they cause? The larvae eat roots and stems, while the adults eat leaves. They are able to transmit wilt and mosaic virus.
How can they be eliminated? Remove beetles by hand. Mulch around plants. Use row covers. Plant resistant varieties when available.
How can they be avoided? Grow plants on trellises.
25. Tarnished Plant Bug
What is it? Tarnished plant bugs are oval-shaped, black, yellow and brown bugs that are ¼ inch long.
When do they arrive? Spring.
What plants are most vulnerable? The most vulnerable plants are beans, celery, chard, lettuce, strawberries, peaches and pears.
What damage can they cause? They suck juice from plants while leaving behind black spots and pitting. They inject toxins into plants that deform flowers, blacken terminal shoots and dwarf fruit. They can also carry fireblight.
How can they be eliminated? Use sticky traps. Remove all weeds and debris from garden. Bacillus bassiana can also help eliminate these bugs.
How can they be avoided? Keep garden clean.
26. Thrips
What is it? Thrips are tiny insects that may be yellow, brown or black with narrow, fringed wings.
When do they arrive? Thrips overwinter in the egg stage and are most present from late spring to the middle of the summer.
What plants are most vulnerable? Onions, beans, cucumbers, corn, melons, squash, tomatoes and many types of flowers are vulnerable to thrips.
What damage can they cause? They are known to scratch plant tissue on all parts of plants. They can also transmit viruses.
How can they be eliminated? Spray neem oil directly on the plants. Neem oil is safe and will not kill off beneficial insects. Spray with soapy water. Remove all weeds and debris from
27. Tomato Fruitworm
What is it? A tomato fruit worm is a 1.5 inch long, red, white or green, shiny worm. The adult form is a moth that is brown.
When do they arrive? They are most visible in late spring.
What plants are most vulnerable? Tomatoes.
What damage can they cause? They are known for eating buds and leaves and tunneling into fruit once it grows.
How can they be eliminated? Remove these worms by hand. Be sure to keep the garden clean of weeds and debris. Trichogramma wasps, Bacillus thuringiensis and beneficial nematodes can also help get rid of tomato fruit worms. Neem oil.
How can they be avoided? Use above methods as prevention.
28. Weevils
What is it? Weevils are a type of beetle that are typically brown or black with a hard shell. They have a long snout and are usually tear-shaped. The larvae are white grubs.
When do they arrive? These pests over-winter in the soil and then come out as adults in late spring.
What plants are most vulnerable? The most vulnerable plants are almost any vegetables, along with apples, blueberries, cherries, peaches, pears, plums, raspberries and strawberries.
What damage can they cause? Weevils create holes in leaves, stems and fruits. Larvae eat roots, stems and fruit. Their eating habits can cause leaves to fall off.
How can they be eliminated? Spray neem oil directly on the plants. Neem oil is safe and will not kill off beneficial insects. Keep garden clean of debris and weeds. Pile up soil around stem area. Rotate crops.
How can they be avoided? Neem oil. Beneficial nematodes and spiders can also help keep weevils away.
29. Whitefly
What is it? A whitefly is about 1/12 inch long, white and scaly-looking. Nymphs are translucent and legless.
When do they arrive? Their eggs over-winter and then hatch in early spring. They may hang around for most of growing season.
What plants are most vulnerable? The most susceptible plants are cucumbers, melons, squash, tomatoes, citrus and many different types of weeds.
What damage can they cause? They typically feed and lay eggs on undersides of leaves. They will fly up together when disturbed. They suck sap from leaves which can result in loss of plant vigor. They are also known to attract ants and mold and to transmit diseases.
How can they be eliminated? Spray neem oil directly on the plants. Neem oil is safe and will not kill off beneficial insects. Spray with soapy water or use sticky traps. Row covers.
How can they be avoided? Neem oil and row covers.
30. Wireworm
What is it? Wireworms are the larvae of click beetles. They are typically about ⅓ to 1.5 inches long, dark brown or yellow legless, hard-shelled worm that is often mistaken for a millipede.
When do they arrive? Eggs are typically laid in the spring. It takes wireworms anywhere from two to six years to reach adulthood.
What plants are most vulnerable? Potatoes, beets, beans, lettuce, carrots, cabbage, corn, onions, muskmelons,
What damage can they cause? They are known to chew roots, tubers,
How can they be eliminated? Use a potato trap by burying halved potatoes, cut-side down to trap worms and then remove and throw away potatoes after two to three days. Beneficial nematodes are another good helper.
How can they be avoided? Alfalfa and clover crops can repel wireworms.
Conclusion
In general, it’s best to try to prevent pests from becoming an issue by having a healthy garden. This all starts with healthy soil. If you have healthy soil, you will be on your way to having healthy and strong plants. The more healthy your plants, the better than can fight off pests and diseases naturally on their own.
Companion planting is your next best defense against pests. Mimicking nature and mixing different varieties of plants together that have different scents will confuse pests and hide the plants they like to attack.
When pests find a garden, it can be a pain to get rid of them. They are called pests for a reason! Keep this list handy to identify and resolve pest problems before they get out of hand.
Check out Our Favorite Products page to find everything you might need to help make your garden a success!
