Aphids

Plants affected: Almost everything — roses, vegetables, fruit trees

Identification: Tiny (1/8 inch) soft-bodied insects in clusters on new growth, undersides of leaves. Green, black, or pink.

Damage: Curled/distorted leaves, sticky honeydew residue, sooty mold, stunted growth.

Organic Control: Strong water spray to knock off, Neem oil, Insecticidal soap, Release ladybugs/lacewings, Companion plant with nasturtiums (trap crop)

Prevention: Encourage beneficial insects. Avoid over-fertilizing (lush growth attracts them). Check plants regularly.

Japanese Beetles

Plants affected: Roses, Grapes, Beans, Raspberries, Linden trees, 300+ plant species

Identification: Metallic green with copper wing covers, 1/2 inch. Feed in groups during daytime.

Damage: Skeletonized leaves (eat between veins). Grubs destroy lawns underground.

Organic Control: Hand-pick into soapy water (morning when sluggish), Neem oil, Milky spore disease (kills grubs), Beneficial nematodes for lawn grubs, Row covers

Prevention: Do NOT use pheromone traps (attract more beetles). Treat lawns for grubs in late summer. Choose resistant plants.

Tomato Hornworm

Plants affected: Tomatoes, Peppers, Eggplant, Potatoes

Identification: Large (3-4 inch) green caterpillar with white V-shaped marks and a horn on rear. Well-camouflaged.

Damage: Devour entire leaves and stems overnight. Can defoliate a tomato plant in days.

Organic Control: Hand-pick (check undersides of leaves), BT (Bacillus thuringiensis) spray, Parasitic wasps (if you see white cocoons on worm, leave it — wasps are hatching), Companion plant with dill/borage

Prevention: Till soil in fall to destroy pupae. Rotate crops. Check plants daily in peak season.

Squash Bugs

Plants affected: Squash, Pumpkins, Cucumbers, Melons

Identification: Flat, shield-shaped, dark gray/brown, 5/8 inch. Copper-colored eggs in orderly rows on leaf undersides.

Damage: Suck sap causing wilting (bacterial wilt). Yellow spotting, then entire vines collapse.

Organic Control: Hand-pick adults and crush egg clusters, Place boards near plants (bugs hide underneath at night — flip and squash in morning), Neem oil on nymphs, Diatomaceous earth around base

Prevention: Clean up all vine crop debris in fall. Use row covers until flowering. Resistant varieties.

Cabbage Worms

Plants affected: Broccoli, Cabbage, Cauliflower, Kale, Brussels sprouts, All brassicas

Identification: Velvety green caterpillars (imported cabbage worm) or green with thin stripe (cabbage looper). White butterflies nearby.

Damage: Large ragged holes in leaves. Bore into broccoli/cabbage heads. Frass (green droppings) on leaves.

Organic Control: BT (Bacillus thuringiensis) spray — very effective, Row covers (best prevention), Hand-pick, Companion plant with thyme, dill, and celery

Prevention: Floating row covers from transplanting until harvest. Inspect regularly. Remove eggs (tiny yellow dots).

Slugs & Snails

Plants affected: Lettuce, Hostas, Strawberries, Seedlings, Most tender plants

Identification: Slimy trails on leaves and soil. Feed at night and rainy days. Hide under boards, pots, debris.

Damage: Irregular holes in leaves. Seedlings eaten to the ground. Slime trails on everything.

Organic Control: Iron phosphate bait (Sluggo — safe around pets/kids), Beer traps, Copper tape barriers, Diatomaceous earth around plants, Hand-pick at night with flashlight

Prevention: Remove hiding places. Water in morning so soil dries by night. Encourage toads, ground beetles, birds.

Deer

Plants affected: Hostas, Tulips, Daylilies, Roses, Vegetables, Almost everything

Identification: Clean, torn edges on leaves/stems (deer have no upper front teeth — they rip). Hoof prints. Droppings.

Damage: Can devastate entire garden overnight. Browse up to 6 feet high.

Organic Control: 8-foot fencing (deer can jump 7 ft), Double-fence system (two 4-ft fences 4 ft apart), Deer repellent sprays (rotate products), Motion-activated sprinklers, Dog in yard

Prevention: Plant deer-resistant varieties. Keep valued plants close to house. Layer resistant plants around vulnerable ones.

Rabbits

Plants affected: Lettuce, Beans, Peas, Beets, Young trees (bark), Flowers

Identification: Clean 45-degree angle cuts on stems. Browse up to 2 feet. Round droppings. Damage worse in spring.

Damage: Eat seedlings to ground. Girdle young tree bark in winter.

Organic Control: Chicken wire fence (2-3 ft tall, buried 6 inches), Hardware cloth around young tree trunks, Blood meal sprinkled around plants, Human hair in garden

Prevention: Fence is the only reliable control. Plant resistant varieties (onions, garlic, lavender, sage). Remove brush piles where they nest.

Groundhogs / Woodchucks

Plants affected: Beans, Peas, Squash, Lettuce, Broccoli, Most vegetables and flowers

Identification: Large (5-14 lbs) rodent. Burrow entrances near garden with excavated dirt mound. Feed early morning/late afternoon.

Damage: Can eat entire rows of vegetables. Devastating to gardens.

Organic Control: Sturdy fence (4 ft above ground + 12 inches buried + 12 inches bent outward underground), Live trap and relocate (check local laws), Motion-activated devices, Cayenne pepper spray

Prevention: Fence with buried apron is only reliable solution. Remove cover near garden. Harvest promptly.

Powdery Mildew ()

Symptoms:

Affected plants:

Treatment:

Prevention: Space plants for air circulation. Water at base, not overhead. Choose resistant varieties. Morning sun dries dew quickly.

Blight (Early & Late) ()

Symptoms:

Affected plants:

Treatment:

Prevention: Rotate crops (3-year cycle). Mulch to prevent splash. Stake plants for airflow. Water at base. Choose resistant varieties.

Root Rot ()

Symptoms:

Affected plants:

Treatment:

Prevention: Never overwater. Ensure good drainage. Raised beds in heavy soil. Don't plant in low spots that collect water.

Damping Off ()

Symptoms:

Affected plants:

Treatment:

Prevention: Use sterile seed-starting mix. Don't overwater. Provide air circulation (small fan). Thin seedlings. Avoid planting too deep.

Mosaic Virus ()

Symptoms:

Affected plants:

Treatment:

Prevention: Buy resistant varieties (TMV-resistant tomatoes). Control aphids (virus vectors). Don't smoke near tomatoes (tobacco mosaic). Wash hands before handling plants.

Fire Blight ()

Symptoms:

Affected plants:

Treatment:

Prevention: Choose resistant varieties. Don't over-fertilize (lush growth is susceptible). Prune in dry weather. Avoid overhead irrigation during bloom.