When to Apply Weed Preventers for Best Results

Product labels give general timing, but weather variations make precision tricky. Use nature's cues for better accuracy.

Lawn crabgrass preventer: Apply when forsythia blossoms start dropping in early spring. This shrub's bright yellow flowers are unmissable when everything else is bare.

Garden beds: For cool-season weeds (henbit, chickweed), apply as soon as soil is workable in spring. For summer weeds (crabgrass, foxtail, spurge), time with forsythia bloom like lawns.

Don't apply too early: Preventers last 8-12 weeks in soil. Early application wastes effectiveness.

How to Apply

Most are granular — use a spreader at the labeled rate. Water in with 1/2 inch of water within a week (irrigate if no rain).

What to Use

Lawns: Synthetic preventers (Bayer, Scotts) often combined with fertilizer. Beds: Preen is a popular bed-only preventer. Organic: Corn gluten meal works nearly as well; many brands offer it.

Precautions

Preventers stop seed germination. Don't apply where you'll sow flower seeds within 3 months or on newly seeded lawns. Spring application allows fall seeding. They don't kill existing perennial weeds (wiregrass, dandelions) — those need physical removal or glyphosate.