How to Kill White Flies Before Planting Vegetables

Place yellow or white sticky traps around the base of where you’ll be planting vegetables as well as hang them on fixtures in your garden. Check the traps weekly to monitor for the arrival of whiteflies as well as catch the ones that are drawn to the light color of the trap.

Plant or grow in containers around your greenhouse and garden small flowering plants, such as pansies or petunias to create a habitat that invites the parasitic wasp Encarsia formosa. Use tunnel row covers to keep the area warm during early spring to encourage the wasps to stay.

Inspect any plants you want to bring into your garden for signs of whiteflies or their small nymph on the undersides of leaves. Use a different nursery supplier or plan to treat the plants according to Step 5 before introducing the plants into your vegetable garden.

Purchase predators of the whitefly and release them into your garden area on the day of planting. Insect predators include ladybeetles, lacewings or minute pirate bugs. If growing in a greenhouse, you can release the predators at any time.

Apply a pyrethrin spray to the undersides of your vegetable plants’ leaves to kill and deter adult whiteflies and use neem spray to stop nymphs. Keep in mind, however, that any insecticide’s goal is to kill insects, beneficial or not, which can disrupt pollination of your vegetables as well as kill the predatory insects that feed on whiteflies.

Lay aluminum foil around the base of plants and weigh it down with rocks or spread a light-colored, reflective mulch around the plants to deter the whiteflies from resting on the undersides of the leaves and encourage them to move on.