What's Eating Your Eggplant?

Floating row cover from transplant through flowering

Cover transplants with lightweight floating row cover (Agribon AG-19 or Reemay, ~$20 for a 10x25 foot piece) the day they go in the ground. Bury or pin the edges so beetles can't crawl under. Leave in place until flowers open, then remove for pollinator access. This is the single most effective home control for flea beetles on eggplant.

Kaolin clay coating, weekly through harvest

Trap crop with Chinese giant mustard

Plant Chinese giant mustard or a sacrificial eggplant decoy 6 to 10 feet upwind of your main row, two weeks before transplanting your crop. Flea beetles prefer the trap crop and concentrate there. Spray the trap with neem or vacuum it weekly to knock the population down before they spread to the main planting.

Strong water blast every 2 to 3 days for 2 weeks

Hold a hose nozzle 12 inches from the affected new growth and spray at high pressure on the underside of leaves. Most aphids dislodge and don't make it back to the plant. Repeat every 2 to 3 days for 2 weeks. The fastest cheapest fix and works without chemicals that harm pollinators.

Insecticidal soap on leaf undersides at dusk

Spray ready-to-use insecticidal soap (Safer Brand, ~$10) on the underside of every leaf and along new growth tips at dusk to avoid burning leaves in sun. Eggplant leaves have fine fuzz that holds the spray well. Reapply every 5 days for 3 rounds to cover the egg-to-adult cycle.

Companion plant sweet alyssum within 3 feet

Plant sweet alyssum and dill within 3 feet of every two eggplants at transplant time. The flowers feed ladybugs and lacewings whose larvae eat aphids. Established plantings keep aphid pressure low without sprays and let the natural enemies build up over the season.

Shower the foliage early morning, every 3 days for 2 weeks

Spray cool water at high pressure on the underside of every leaf for 30 seconds. Mites can't reattach quickly when knocked off and they hate humid leaf surfaces. Eggplant tolerates a hard rinse well, especially in the heat. Repeat every 3 days for 2 weeks.

Neem oil at dusk, every 5 days for 3 rounds

Mulch and water deeply to reduce heat stress

Mulch 2 to 3 inches deep with straw or shredded leaves to keep the root zone cool and moist. Water deeply twice a week instead of shallow daily watering. Stressed dry eggplant invites mite explosions. A well-watered plant in cool soil holds mite populations down on its own.

Hand-pick at dusk under a blacklight

Bt spray on leaf undersides at dusk

Mix 1 teaspoon Bt (Monterey or Safer Caterpillar Killer, ~$15) per quart of water. Spray the underside of every leaf at dusk because Bt breaks down in sunlight. Reapply after rain or every 7 days. Bt only affects caterpillars and is safe for bees and pollinators visiting the eggplant flowers.

Leave parasitic wasp cocoons alone

If you find a hornworm covered in white rice-grain cocoons, leave that one in the garden. Those are braconid wasp larvae that already killed it from inside. The emerging wasps will hunt down the rest of the hornworms in your bed.

Insecticidal soap on leaf undersides, every 5 days for 3 rounds

Strong water blast on leaf undersides every 2 days

Aim a hose nozzle up at the underside of every leaf at high pressure. The nymphs are soft and don't survive being knocked off. Adults fly back but their numbers drop with consistent blasting. Free, no chemicals, and safe around the flowers and pollinators.

Remove crop debris in fall

Lace bug eggs overwinter on dead eggplant leaves and stems left in the garden. Pull and bag every plant after frost. Do not compost. Clean beds break the lifecycle and keep next season's pressure low. This is the single highest-leverage move for lace bug control.