How to Prevent Crabgrass Seed Germination
- 1). Apply a pre-emergent crabgrass herbicide to the lawn according the the manufacturer's instructions. Pre-emergent herbicides must be applied before crabgrass seed germinates. Crabgrass seed begins to germinate when the soil temperature reaches 55 to 60 degrees F for seven to 10 consecutive days. This is usually around March 1st. However, in warm climates, this has been known to happen as early as January. To be safe, apply pre-emergent herbicide roughly three weeks before you expect the crabgrass to germinate.
- 2). Water the lawn with 1 to 2 inches of water immediately after the herbicide application. This will help the herbicide penetrate the soil.
- 3). Re-apply the pre-emergent herbicide in four months if the crabgrass seed has yet to germinate.
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