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How to Manage Pests

The UC Guide to Healthy Lawns

Preplant weed control

Preplant weed control may be needed if the site or topsoil that has been brought into the site contains many weeds or weed seeds. Before planting, check the area for weeds. Cultivation, herbicide application, and soil solarization can be used alone or in combination for weed management. Annual weeds are much easier to control than perennials. Lawns planted with seed, stolons, or plugs will be quite susceptible to weed invasion, whereas sod-planted turf can smother and outcompete many weeds.

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Summer cultivation for perennials
Herbicide application


  • Irrigate to allow germination of weeds in planting bed.
  • Follow up with a shallow (less than 1 inch) cultivation after weeds have emerged but before they get too big (usually before they have 4 leaves).
  • Repeat the irrigation and cultivation cycle two or three times for best results.

Summer cultivation for perennials

For perennial weeds, it is ideal to repeatedly cultivate soil in summer, keeping it completely dry for several months to dehydrate propagules (stems, rhizomes, or tubers).

Herbicide application

  • Irrigate to allow germination of weed seeds in planting bed.
  • Apply non-selective herbicide, such as glyphosate.
  • Repeat the irrigation and herbicide cycle if necessary.


Solarization is very effective during the hottest part of the year in warmer parts of California. Six weeks are required for best results.

Digging out weeds with a scuffle hoe

Weeds and weed management

Statewide IPM Program, Agriculture and Natural Resources, University of California
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