How to Treat Fleas in the Yard

Flea larvae feed on organic matter and flea dirt (feces) dropped by adult fleas. Before applying any products, you must remove their hiding spots.

• Rake up dead leaves, thick grass clippings, and pine needles.
• Clear out the damp, decaying organic matter that accumulates directly under your deck or porch.
• Remove old, unused dog houses or rotting wood piles where feral cats or skunks might be sleeping at night.

Because direct sunlight is your greatest free weapon against fleas, you need to maximize the sun exposure on your soil.

Mow your lawn short (but not so short that you kill the grass). Trim back heavy, low-hanging shrubs and dense ivy that create permanent shade canopies over the dirt. By exposing these dark corners to the harsh midday sun, you naturally sterilize the soil and make it inhospitable for flea eggs to develop.

Using a handheld or push spreader, apply an insecticidal yard granule (products containing Bifenthrin work exceptionally well in California soil) to the remaining high-risk zones. Focus heavily on:

• The soil directly under trees and large bushes.
• The perimeter of your house, especially under roof eaves and crawlspace vents.
• The exact spots where your dog likes to lay down and rest in the shade.

Crucial Step: Most granular insecticides must be “watered in” to activate. Use your hose to lightly wet the treated areas. Keep pets and children off the yard until it is completely dry.

For immediate knockdown of jumping adult fleas, connect a hose-end liquid insecticide spray to your garden hose. Spray the liquid heavily into the deep recesses under your deck, into the mulch beds, and along the perimeter fences where wild animals (like opossums) might travel at night.