Identifying common vegetable garden pests and cultural control
Last reviewed September 2026 · written from public-domain USDA/NOAA data and Cooperative Extension references — see how we source data
Most home-garden pest problems are manageable without chemical controls once you can identify what is actually causing the damage and lean on prevention. This guide covers identification and cultural control, not product recommendations or application rates.
Read the damage first
Different pests leave distinct signatures: ragged chewed leaf edges, leaves reduced to a skeleton of veins, small round holes, a sudden wilting vine, or a plant that looks fine but is not growing. Identify the pattern — and ideally the insect itself — before deciding on any response.
Read the damage: what is eating your plants?
Prevention beats reaction
Crop rotation breaks the cycle for pests that overwinter in soil near their host family. Healthy, unstressed plants in good soil resist pests better than struggling ones. Floating row cover physically blocks many pests from ever reaching susceptible crops like brassicas and cucurbits. Flowering plants nearby bring in predatory insects that do a lot of the work for you — see attracting pollinators.
Physical controls that work
Row cover laid over crops at planting time and sealed at the edges keeps out flea beetles, cabbage worms and squash vine borers entirely. Remove it from squash and cucumbers when the female flowers open so bees can pollinate.
A collar of cardboard or a cut-down cup pushed an inch into the soil around each transplant stops cutworms. Hand-picking into a jar of soapy water deals with hornworms, beetles and caterpillars, and a sharp spray of water knocks aphids off and often keeps them off.
Let predators help
Ladybugs, lacewings, hoverflies, parasitic wasps, ground beetles, birds and toads eat a large share of garden pests. Broad-spectrum sprays kill them along with the pests, which often makes the next outbreak worse.
Small flowers such as sweet alyssum, dill, cilantro left to flower, and yarrow feed adult predators, so they stay and breed near your crops.
Common culprits and their signs
Aphids: clusters of small soft-bodied insects on new growth, sticky honeydew residue, and curled leaves. Squash vine borer: a healthy-looking vine wilts suddenly, with sawdust-like frass near the base of the stem. Cabbage worms: ragged holes in brassica leaves and small green caterpillars. Slugs: irregular holes and silvery slime trails, worse after rain and at night.
More pests worth knowing
Flea beetles: many tiny round holes, like buckshot, in the leaves of brassicas, eggplant and arugula, especially on young plants in spring. Cutworms: seedlings cut clean through at the soil line overnight. Spider mites: fine yellow speckling on leaves and faint webbing underneath, worst in hot, dry weather.
Tomato hornworms strip leaves and green fruit fast and leave large dark droppings - see tomato hornworms. For soft clusters on new growth see aphids, and for night-time holes and slime see slugs and snails.
When to get more help
For anything beyond hand-picking, row cover or removing badly affected material, a local Cooperative Extension office can positively identify the pest and recommend the least-toxic option appropriate for your specific region and crop — advice that depends too much on local conditions to generalize here.
Timing and routine
A second sowing of squash in early summer often dodges the first generation of squash vine borers, and fall brassicas usually suffer less from flea beetles than spring ones.
Walk the garden twice a week and turn over a few leaves on each crop. Most pest problems start small and are easy to deal with in the first few days.
Common questions
How do I find out what is eating my plants?
Look at the pattern of damage, then check the plants with a flashlight after dark - slugs, cutworms and many caterpillars feed at night. Look under leaves and at the base of stems, and check for droppings, slime trails or eggs.
What is a natural way to get rid of aphids?
Knock them off with a strong spray of water every few days and let predators such as ladybugs and hoverfly larvae build up. Aphids often cluster on soft, over-fed growth, so go easy on nitrogen fertilizer.
Are all garden insects pests?
No. Most insects in a garden are harmless or helpful - pollinators, predators and decomposers. Identify an insect before acting on it; ladybug larvae, for example, look alarming but eat large numbers of aphids.
Does row cover really keep pests off?
Yes, if it goes on at planting time before pests arrive and the edges are sealed with soil or weights. It is the most reliable control for flea beetles, cabbage worms and squash vine borers. It does not help against pests already in the soil under it.