Garden Pest Directory: Complete Identification & Control Guide
Identifying garden pests is the first step in finding earth-friendly solutions to protect your plants. This comprehensive directory covers the most common garden pests found in North America, helping you quickly identify problems and implement effective organic control methods.
Keep in mind that 95% of garden visitors are either helpful or harmless. Beneficial insects like ladybugs, lacewings, and parasitic wasps actually help control pest populations. The key is learning to distinguish between friend and foe in your garden ecosystem.
Caterpillars
These are the larval forms of butterflies and moths with chewing mouthparts that can quickly destroy leaves and flowers.
| Pest | Identification | Damage | Organic Control |
|---|---|---|---|
| Armyworm | Gray or green caterpillars with stripes, move in groups | Skeletonized leaves, circular feeding patterns | Bt spray, beneficial nematodes, bird houses |
| Cabbage Looper | Green caterpillars with white stripes, arch their backs | Circular holes in cole crop leaves | Bt applications, hand removal, row covers |
| Cabbageworm | Green caterpillars with yellow stripes, 1 inch long | Large irregular holes in brassica leaves | Hand picking, Bt spray, beneficial wasps |
| Codling Moth | Small pink caterpillars inside fruits | Wormy apples and pears, entry holes in fruit | Pheromone traps, beneficial nematodes, tree bands |
| Corn Earworm | Green, brown or pink caterpillars with stripes | Damaged corn ears, holes in tomato fruits | Bt spray, beneficial predators, mineral oil |
| Grasshoppers | Large jumping insects with powerful hind legs | Chewed leaves and stems, widespread defoliation | Row covers, beneficial predators, diatomaceous earth |
| Pickleworm | Yellowish caterpillars with spotted pattern | Holes in cucumber family fruits and stems | Bt spray, row covers, crop rotation |
| Tomato Hornworm | Large green caterpillars with white stripes and horn | Severe defoliation of tomato plants | Hand picking, Bt spray, parasitic wasps |
Small Insect Pests
Common insects and small creatures that cause damage by sucking plant juices or chewing.
| Pest | Identification | Damage | Organic Control |
|---|---|---|---|
| Aphids | Small soft-bodied insects in clusters, various colors | Yellowing leaves, curled foliage, sticky honeydew | Water spray, beneficial insects, insecticidal soap |
| Fruit Fly | Small flies around ripe or rotting fruit | Maggots in fruit, premature fruit drop | Fruit traps, sanitation, beneficial nematodes |
| Fungus Gnat | Small dark flies around soil surface | Root damage from larvae, poor plant growth | Yellow sticky traps, reduce watering, beneficial nematodes |
| Leafhopper | Small wedge-shaped jumping insects | Stippled leaves, reduced plant vigor | Row covers, beneficial predators, reflective mulch |
| Leafminer | Tiny flies whose larvae tunnel in leaves | White trails or blotches in leaves | Remove affected leaves, beneficial parasites, spinosad |
| Mealybug | White cottony insects on stems and leaves | Yellowing leaves, stunted growth, honeydew | Rubbing alcohol, insecticidal soap, beneficial predators |
| Pea Weevil | Small brown beetles with spotted pattern | Holes in pea pods and seeds | Row covers, crop rotation, beneficial predators |
| Pepper Maggot | Small white maggots inside pepper fruits | Rotting peppers, premature fruit drop | Yellow sticky traps, sanitation, crop rotation |
| Scale | Small dome-shaped insects on stems and leaves | Yellowing leaves, branch dieback, honeydew | Horticultural oil, beneficial predators, systemic controls |
| Spider Mites | Microscopic pests creating fine webbing | Stippled bronze leaves, fine webbing | Increase humidity, predatory mites, insecticidal soap |
| Thrips | Tiny slender insects, yellow to dark brown | Silvery stippling on leaves, black specks | Blue sticky traps, beneficial predators, spinosad spray |
| Whiteflies | Tiny white flying insects on leaf undersides | Yellowing leaves, sooty mold, reduced vigor | Yellow sticky traps, reflective mulch, beneficial predators |
Beetles
Hard-shelled insects with chewing mouthparts that feed on leaves, fruits, and roots.
| Pest | Identification | Damage | Organic Control |
|---|---|---|---|
| Asian Lady Beetle | Orange beetles with varying spots | Can become nuisance pests indoors | Seal entry points, vacuum removal, beneficial habitat |
| Asparagus Beetle | Blue-black beetles with cream spots | Defoliation of asparagus ferns | Hand picking, beneficial insects, clean debris |
| Bean Leaf Beetle | Red or yellow beetles with black spots | Holes in bean leaves, root feeding by larvae | Row covers, crop rotation, beneficial predators |
| Blister Beetle | Long narrow beetles, various colors | Defoliation of vegetables and ornamentals | Hand picking with gloves, beneficial predators |
| Colorado Potato Beetle | Orange beetles with black stripes | Defoliation of potato family plants | Hand picking, beneficial nematodes, crop rotation |
| Corn Rootworm | Yellow-green beetles, white larvae in soil | Root damage, lodging of corn plants | Crop rotation, beneficial nematodes, beetle traps |
| Cucumber Beetle | Yellow beetles with stripes or spots | Feeding damage, disease transmission | Row covers, trap crops, beneficial nematodes |
| Curculio | Small brown weevils with long snouts | Holes in fruits, especially stone fruits | Tree bands, beneficial nematodes, sanitation |
| Flea Beetle | Small dark beetles that jump | Small holes in leaves, especially young plants | Row covers, diatomaceous earth, beneficial nematodes |
| Japanese Beetle | Metallic green beetles with copper wings | Skeletonized leaves on various plants | Hand picking, beetle traps, beneficial nematodes |
| Lily Leaf Beetle | Bright red beetles with black heads | Defoliation of lilies and fritillaries | Hand picking, beneficial parasites, neem oil |
| Mexican Bean Beetle | Copper beetles with 16 black spots | Skeletonized bean leaves | Row covers, hand picking, beneficial insects |
| Sweet Potato Weevil | Dark weevils with long snouts | Tunnels in sweet potato roots | Certified clean plants, crop rotation, pheromone traps |
Borers
Pests that tunnel into plant stems, trunks, and fruits, often causing plant death.
| Pest | Identification | Damage | Organic Control |
|---|---|---|---|
| European Corn Borer | Tan caterpillars with dark heads | Tunnels in corn stalks, broken plants | Bt applications, beneficial wasps, clean debris |
| Peach Tree Borer | White caterpillars with brown heads | Gummy sap at tree base, weakened trees | Pheromone traps, beneficial nematodes, tree wraps |
| Squash Vine Borer | White caterpillars in plant stems | Wilting vines, sawdust-like frass | Row covers, beneficial nematodes, stem surgery |
At or Below Ground Pests
Pests that attack plants from underground or at soil level.
| Pest | Identification | Damage | Organic Control |
|---|---|---|---|
| Carrot Rust Fly | Small black flies, white maggots in roots | Tunnels in carrot and parsnip roots | Row covers, crop rotation, beneficial nematodes |
| Celery Leaftier | Small caterpillars that tie leaves together | Webbed leaves, feeding damage | Hand removal, Bt spray, beneficial predators |
| Cutworm | Gray or brown caterpillars that curl up | Severed seedlings at soil level | Collar barriers, beneficial nematodes, hand picking |
| Earwig | Brown insects with pincer-like tails | Holes in leaves and flowers | Newspaper traps, beneficial predators, remove debris |
| Fire Ant | Red ants that build mound nests | Stings, root damage, seed eating | Beneficial nematodes, diatomaceous earth, baits |
| Nematodes | Microscopic roundworms in soil | Root galls, stunted plant growth | Resistant varieties, crop rotation, soil solarization |
| Root Maggot | White legless larvae in soil | Tunneling in roots of brassicas and onions | Row covers, beneficial nematodes, crop rotation |
| Root Weevil | Brown weevils, white grubs in soil | Notched leaves, root damage | Beneficial nematodes, sticky barriers, night collection |
| Slug | Soft-bodied mollusks leaving slime trails | Irregular holes in leaves and fruits | Beer traps, copper barriers, iron phosphate baits |
| Snail | Soft-bodied mollusks with shells | Holes in tender plant parts | Hand picking, copper barriers, beer traps |
| Wire Worm | Hard yellow-brown larvae in soil | Holes in root vegetables, seed damage | Crop rotation, beneficial nematodes, potato traps |
True Bugs
Shield-shaped or oval insects that pierce plants to feed on sap.
| Pest | Identification | Damage | Organic Control |
|---|---|---|---|
| Four-Lined Plant Bug | Yellow-green bugs with black stripes | Round spots on leaves, wilting | Remove affected plants, beneficial predators, row covers |
| Harlequin Bug | Black and orange shield-shaped bugs | Wilting, yellowing of brassica plants | Hand picking, beneficial predators, crop rotation |
| Tarnished Plant Bug | Brown oval bugs with yellow markings | Dimpled fruits, stunted growth | Row covers, beneficial predators, weed control |
| Squash Bug | Gray-brown shield-shaped bugs | Wilting vines, yellowing leaves | Hand picking, beneficial predators, crop rotation |
| Stink Bug | Shield-shaped bugs, various colors | Dimpled fruits, wilting leaves | Row covers, beneficial predators, kaolin clay |
Beneficial Insects
Remember that some insects are your garden allies and should be protected and encouraged.
| Beneficial | Identification | Benefits | How to Attract |
|---|---|---|---|
| Ladybugs | Red or orange beetles with spots | Eat aphids, scale, mites | Diverse flowers, avoid pesticides, shelter areas |
| Parasitic Wasps | Small wasps, often metallic colored | Parasitize many pest insects | Small flowers, diverse plants, minimal disturbance |
| Green Lacewing | Delicate green insects with lacy wings | Larvae eat aphids, thrips, mites | Diverse flowers, shelter plants, water sources |
Organic Prevention Strategies
Garden Hygiene: Remove plant debris, weeds, and fallen fruit that harbor pests
Crop Rotation: Disrupt pest life cycles by changing plant families annually
Beneficial Habitat: Plant diverse flowers to attract helpful predatory insects
Physical Barriers: Use row covers, copper strips, and collar barriers
Healthy Soil: Strong plants in fertile soil resist pest damage better
Regular Monitoring: Check plants weekly for early pest detection
Companion Planting: Use repellent plants like marigolds and garlic
FAQ
Q: How can I tell if an insect is beneficial or harmful? A: Beneficial insects often move quickly, have longer antennae, or are found eating other insects. When unsure, observe their behavior before taking action.
Q: When should I start looking for garden pests? A: Begin monitoring in early spring as plants emerge, and continue weekly throughout the growing season. Many pests are most active during cooler morning and evening hours.
Q: Are organic control methods as effective as chemical pesticides? A: Yes, when used properly and consistently. Organic methods often provide longer-lasting control by working with natural ecosystems rather than disrupting them.
Q: How do I encourage beneficial insects in my garden? A: Plant diverse flowering plants with small flowers, provide water sources, avoid broad-spectrum pesticides, and create shelter with diverse plantings.
Q: What should I do if I find a few pests on my plants? A: Don't panic. A few pests are normal. Monitor for a few days to see if beneficial insects control them naturally. Hand-picking and spot treatments are often sufficient for small infestations.
Remember, successful pest management is about balance, not elimination. A healthy garden ecosystem will naturally keep most pest populations under control.
This comprehensive guide covers 35+ common North American garden pests with organic, earth-friendly control solutions. Regular monitoring and prevention are the keys to successful pest management.
