The Dirty Dozen: 12 Bad Garden Bugs and How to Get Rid of Them
Consider this your garden's wanted poster. Dead or alive, preferably dead, these twelve are the reason your tomatoes look like they lost a fight.
The good news: once you know who you're dealing with, most of them are easy to stop. Usually all it takes is your hands, a garden hose and a jar of soapy water. Drop the bugs in and they're done.
Getting rid of garden pests is also a lot more fun with kids. Nothing motivates a reluctant helper like the words "bug hunt." Hand them gloves and a jar, and make sure everyone washes up afterward.
Here's your lineup.
The Dirty Dozen Bad Garden Bugs
1. Aphids
What they look like: Tiny, pear-shaped bugs in green, black, red, yellow or brown, clustered on new growth and the undersides of leaves.
What they do: They suck the sap out of almost any plant, leaving curled, yellow leaves and a sticky coating called honeydew. If ants are marching up and down your plant, look for aphids. Ants "farm" them for the honeydew.
How to get rid of them: Blast them off with a hard spray from the hose, every couple of days for a week. For a bad infestation, spray with insecticidal soap. And invite the good guys: ladybugs and lacewings eat aphids by the hundreds.
10 Most Wanted Good Garden Bugs →
2. Corn Earworms
What they look like: Striped caterpillars, green, brown or pink, tucked into the tip of an ear of corn.
What they do: The moths lay eggs on corn silk, and on tomato leaves too. The caterpillars tunnel into the top of the ear and eat the kernels, leaving a hole and a mess.
How to get rid of them: Peel back the tips and pick them off. To head them off, put a few drops of mineral oil on the silk at the tip of each ear once the silk starts to wilt and turn brown, about 5 days after it first appears.
3. Tomato Hornworms
What they look like: Big, bright green caterpillars, up to 4 inches long, with white stripes and a little horn on the back end. They're also very good at hiding.
What they do: They can strip a tomato plant of its leaves, and take bites out of the fruit, practically overnight.
How to spot them: Look for missing leaves, bare stems and little black droppings on the leaves below. Then look up.
How to get rid of them: Handpick them as soon as you see them, and drop them in soapy water. One exception: if a hornworm is covered in tiny white cocoons that look like grains of rice, leave it alone. Those are baby parasitic wasps, one of the good bugs, and they're about to take care of your problem for you.
4. Vine Borers
What they look like: The adult is a moth that looks like a wasp, with an orange body, black dots and a half-inch-long body. The real trouble is its larva, a fat white grub that lives inside the stem.
What they do: They tunnel into the stems of summer squash, winter squash and pumpkins. The plant wilts suddenly, even though it's watered.
How to spot them: Look for a small hole near the base of the stem, with sawdust-like goo coming out.
How to get rid of them: Slit the stem lengthwise with a sharp knife, right above the hole. Pull out the grub, then bury the cut part of the stem in moist soil so it can grow new roots. To prevent them, cover young plants with row covers until they start to bloom, and wrap the base of each stem in a strip of aluminum foil.
5. Cucumber Beetles
What they look like: Small, yellow-green beetles with black stripes or black spots, often hiding on the undersides of leaves.
What they do: They chew leaves, flowers and fruit, and they spread bacterial wilt, which can kill cucumbers and melons.
How to get rid of them: Handpick them, or knock them into soapy water in the early morning, when they're sluggish. Cover young plants with row covers until they flower, then take the covers off so the bees can pollinate. Yellow sticky traps help too.
6. Cutworms
What they look like: Fat, gray or brown caterpillars that curl into a C shape when you disturb them. They hide in the soil during the day.
What they do: They come out at night and chew through young stems right at soil level. You plant a seedling one day, and the next morning it's lying on the ground.
How to get rid of them: Make a collar out of a toilet paper tube, or a paper towel tube cut into 3-inch pieces. Slip it around each seedling and push it about an inch into the soil. You can also go hunting at night with a flashlight and pick them off.
7. Cabbage Loopers
What they look like: Pale green caterpillars with thin white stripes. They inch along by looping up the middle of their bodies.
What they do: They chew ragged holes in broccoli, cabbage, cauliflower, kohlrabi and collards, and they'll eat tomatoes, spinach and cucumbers too.
How to get rid of them: Handpick them. For a big infestation, spray with Bt (Bacillus thuringiensis), a natural bacteria that only affects caterpillars. Row covers keep the moths from laying eggs in the first place.
8. Mealybugs
What they look like: Tiny white, fuzzy insects that look like little bits of cotton, tucked where leaves meet stems.
What they do: They suck sap, weaken plants and leave behind sticky honeydew that grows black mold. They're also a common houseplant pest.
How to get rid of them: Spray them off with water, or dab each one with a cotton swab dipped in 70% rubbing alcohol. Test it on one leaf first and wait a day. Some plants don't like it. Keep the rubbing alcohol out of reach of kids and pets.
9. Spider Mites
What they look like: Barely visible specks, usually red or yellowish. To check, hold a sheet of white paper under a leaf and tap it. If the specks start moving, you've got mites.
What they do: They suck the life out of leaves, leaving tiny yellow or white speckles, and in bad cases, fine webbing. They love hot, dry, dusty weather.
How to get rid of them: Spray the plant hard with water, especially the undersides of the leaves, every few days. Keeping plants well watered and less dusty makes them less inviting.
10. Snails and Slugs
What they look like: You know what they look like. Snails bring their own house; slugs travel light.
What they do: They chew ragged holes in leaves, stems, fruit and bulbs, mostly at night. They can wipe out a row of seedlings in one evening and leave shiny slime trails behind.
How to get rid of them: Go out with a flashlight after dark or after a rain and handpick them. Or set a beer trap: sink a shallow container into the soil with the rim about an inch above ground, then fill it with beer. Even slugs can't resist a good happy hour. Check it every morning.
If you use slug bait, choose one made with iron phosphate. Avoid metaldehyde baits, which are highly toxic to dogs and cats.
11. Earwigs
What they look like: Brown insects with a pair of pincers on their back end. Surprise houseguest, uninvited. They love to hide in cut roses and sneak into the house.
What they do: They chew holes in leaves, flowers and soft fruit. In fairness, they also eat aphids, so a few aren't a disaster.
How to get rid of them: Roll up a damp newspaper and leave it in the garden overnight. In the morning, shake the earwigs out into a bucket of soapy water. Genuinely satisfying, if a little gruesome.
12. Whiteflies
What they look like: Tiny white flying insects that burst up in a cloud when you brush the plant, like they wanted you to know they were there.
What they do: They suck sap from the undersides of leaves, leaving yellowing leaves and sticky honeydew.
How to get rid of them: Hose off the undersides of the leaves, spray with insecticidal soap and hang yellow sticky traps. Hang the traps among the affected plants, not near your flowers, so you don't catch the bees.
Before You Kill a Garden Bug, Identify It
Not every bug in your garden is a bad guy. Ladybug larvae look like tiny alligators. Plenty of wasps are hunting your pests for you. And bees are doing the pollinating your vegetables need. Squash the wrong bugs and you'll end up with more pests, not fewer.
If you're not sure what you're looking at, snap a photo and compare it with a good bug guide, or ask your local nursery or Cooperative Extension office.
10 Most Wanted Good Garden Bugs →
Start With the Least Drastic Solution
1. Identify the pest. Make sure the bug you see is the one doing the damage.
2. Decide how bad it is. A few chewed leaves are cosmetic. A plant that's wilting or stripped bare needs help.
3. Remove the pests by hand. Handpick them, prune off the infested leaves or blast them with the hose.
4. Protect plants before the pests arrive. Row covers, cutworm collars and copper tape stop a lot of problems before they start.
5. Protect the good bugs. Grow flowers like dill, alyssum and yarrow to attract the insects that eat pests.
6. Bring out stronger products only when you need them. Start with insecticidal soap, Bt or neem oil. Use any pesticide exactly as the label says, spray in the early morning or evening when bees aren't flying, never spray open flowers and keep kids and pets away until it's dry.
A garden is an ecosystem, not an operating room.
When Garden Damage Isn't Caused by Bugs
Sometimes the bugs are innocent. Disease, too much or too little water, missing nutrients and weather can all cause damage that looks like pests. Read the clues:
- Holes and missing chunks: chewing insects like caterpillars, beetles, slugs and snails
- Sticky leaves: sap-suckers like aphids, whiteflies and mealybugs
- Fine webbing and speckled leaves: spider mites
- A seedling cut off at the soil line: cutworms
- Winding white trails inside a leaf: leaf miners
- Yellow or brown leaves and no bugs anywhere: check the watering, the soil and the weather before you blame a bug
Bad Garden Bugs FAQ
What is the most common garden pest? Aphids. They attack almost every kind of plant. The good news is they're easy to knock off with a hard spray of water.
How do I get rid of garden pests naturally? Handpick them, hose them off, use row covers and barriers, and attract the good bugs, like ladybugs and lacewings, that eat pests. For tougher cases, try insecticidal soap or Bt.
What's eating holes in my plant leaves? Most likely caterpillars, beetles, slugs or snails. Check at night with a flashlight to catch them in the act.
Do beer traps really work for slugs? Yes. Sink a shallow container so the rim sits about an inch above the soil, fill it with beer and empty it every morning.
Are homemade dish soap sprays safe for plants? Not always. Many dish soaps are degreasers that can burn leaves. A store-bought insecticidal soap made for plants is safer and works better.
The Bottom Line on Bad Garden Bugs
A few pests are part of every garden. You don't need to wage war on every bug you see. Learn the dirty dozen, act fast when you spot them and let the good bugs do some of the work for you.
Keep Going
Keep your garden, and your family, thriving with these related guides:
• 10 Most Wanted Good Garden Bugs: The helpful insects you want patrolling your garden.
• Backyard Family Living: Make your outdoor space work for kids, pets and grown-ups.
• Easy Gardening With Kids: Simple garden projects that get kids digging, planting and picking.
• Dealing With Wasps: When wasps are helpful, and when they need to go.
• Ant Problem? Less Toxic Solutions: Get rid of ants without harsh chemicals.
• Green Cleaning Guide: Safer, simpler cleaning with fewer products.
• Family Pets: Keep pets safe from garden chemicals, toxic plants and slug bait.
• Safe at Home: Practical safety tips for every room, and the backyard.
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