GARDEN FOES
A quick-reference guide to common garden pests, when they appear, and the plants they target.
APHIDS Tiny sap-feeding insects that cluster on new growth. Look for curled leaves, yellowing and sticky honeydew. MOST ACTIVE Spring–fall; often peak in mild spring weather FAVORITE PLANTS Roses, tomatoes, peppers, lettuce, kale, beans |
THRIPS Very small, slender insects that cause silvery streaks, distorted growth and damaged flowers. MOST ACTIVE Late spring–summer; warm, dry weather FAVORITE PLANTS Roses, petunias, peppers, onions, strawberries |
JAPANESE BEETLES Metallic green and copper adults that skeletonize foliage and chew flowers. MOST ACTIVE June–August; often peak in July FAVORITE PLANTS Roses, grapes, raspberries, beans, hibiscus |
TOMATO HORNWORMS Large green caterpillars that can quickly strip leaves from stems. MOST ACTIVE July–September FAVORITE PLANTS Tomatoes, peppers, eggplants, potatoes |
SQUASH BUGS Brownish-gray sap feeders that can cause yellowing and wilting. MOST ACTIVE Late spring–early fall; build up in summer FAVORITE PLANTS Pumpkins, zucchini, summer and winter squash |
CUCUMBER BEETLES Yellow beetles with black stripes or spots; feed on plants and may transmit bacterial wilt. MOST ACTIVE Late spring–summer FAVORITE PLANTS Cucumbers, melons, squash, pumpkins |
SQUASH VINE BORERS Larvae tunnel into stems and may cause sudden wilting despite adequate watering. MOST ACTIVE June–August; timing varies by region FAVORITE PLANTS Zucchini, summer squash, pumpkins |
SPIDER MITES Tiny arachnids that cause pale speckling and sometimes fine webbing. MOST ACTIVE Hot, dry summer weather; year-round indoors FAVORITE PLANTS Tomatoes, cucumbers, beans, strawberries, roses |
CABBAGEWORMS Green caterpillars that chew holes in leaves of brassica crops. MOST ACTIVE Spring–fall FAVORITE PLANTS Cabbage, broccoli, kale, cauliflower, collards |
COLORADO POTATO BEETLES Yellow-orange, black-striped beetles; adults and larvae consume foliage. MOST ACTIVE May–August FAVORITE PLANTS Potatoes, eggplants; sometimes tomatoes |
HARLEQUIN BUGS Black-and-red/orange shield-shaped bugs that cause spotting, wilting and stunted growth. MOST ACTIVE Late spring–early fall; often peak late summer FAVORITE PLANTS Cabbage, broccoli, kale, collards, mustard greens |
WHITEFLIES Tiny white, moth-like insects that gather beneath leaves and suck plant sap, causing yellowing and sticky honeydew. MOST ACTIVE Late spring–fall; thrive in warm weather and greenhouses FAVORITE PLANTS Tomatoes, peppers, cucumbers, beans, ornamentals |
FLEA BEETLES Black tiny, jumping beetles that chew small, round “shot holes” in leaves; seedlings are especially vulnerable. MOST ACTIVE Spring–summer; often most damaging early in the season FAVORITE PLANTS Eggplants, potatoes, tomatoes, radishes, arugula, kale NEED MORE HELP? For more information on pest identification, prevention, and management, please contact your local agricultural extension office for guidance and recommendations specific to your area. |
SEASONAL NOTE Timing is approximate for the Northeastern and Mid-Atlantic U.S.; warmer climates may see earlier or longer activity.