Broccoli, Cole crops: Aphids

Biology

Aphids are small, pear-shaped, soft-bodied insects. They may range in color from yellowish to a waxy gray-green. Aphids typically feed on the underside of leaves, in buds, or in heads of broccoli or cauliflower. Aphid feeding can cause foliage to yellow. Wilting or stunting of plants may occur if infestations are severe. Aphid feeding produces honeydew, a sweet, sticky material which may attract ants or become covered with a dark growth of sooty mold. Some species can overwinter as eggs on plant debris.

Management Options

Use Integrated Pest Management (IPM) for successful plant problem management.

Non-chemical Management

Select non-chemical management options as your first choice!

• Remove plant debris from the garden in the fall.
• Encourage natural enemies including ladybird beetles, lacewings, syrphid (hover) fly larvae, and parasitic wasps. Avoid use of broad-spectrum insecticides which kill beneficial insects.
• Hand-wipe to control small, localized infestations.
• Wash aphids from plants with a strong stream of water.
• Control honeydew-feeding ants, which may protect aphid colonies from predators.
• Provide proper nutrition. High levels of nitrogen encourage aphid reproduction. Switch to a slow-release or low-nitrogen fertilizer.

Chemical Management

IMPORTANT: Visit Home and Garden Fact Sheets for more information on using pesticides.

• Apply when aphids first appear. Repeat at 8- to 10-day intervals.
• Do not apply unless leaves are dry.
• Thorough coverage of the foliage is important, including lower leaf surfaces.
• A surfactant (spreader) may need to be added to some products.
• Read the product label for timing between last application and harvest.
• Insecticidal soaps may require more than one application.

Approved Pesticides

Listed below are examples of pesticides that are legal in Washington. Always read and follow all label directions.

• Safer Brand BioNEEM Multi-Purpose Insecticide and Repellent Concentrate [Organic]
  Active ingredient: azadirachtin [EPA registration number: 70051-6-42697]
• Safer Brand Insect Killing Soap with Seaweed Extract II [Organic]
  Active ingredient: potassium salts of fatty acid [EPA registration number: 42697-59]
• Surround At Home Crop Protectant
  Active ingredient: kaolin clay [EPA registration number: 61842-18-56872]
• This list may not include all products registered for this use.

Additional Images