Lawn Weed Control Basics: Healthy Grass, Mechanical Removal, and Smart Herbicide Use

Consistent weed control requires a three-pronged approach—no single method suffices.

1. Healthy Lawn (Cultural)

Dense, properly fertilized, watered, and mowed turf leaves no room for weeds. Weeds invade bare/thin areas first.

2. Mechanical

• Mow at correct height/frequency—many weeds can’t tolerate it.
• Hand-pull annuals (effective, good exercise).
• Remove new/strange weeds immediately to prevent spread.
• Perennial weeds need chemical help.

3. Chemical

• Herbicides are rigorously tested for safety and efficacy.
• Pre-emergents: prevent germination. Apply spring (forsythia bloom) for summer weeds; Sept–Oct for winter weeds. Water in.
• Post-emergents: kill existing weeds. Match product to weed type (broadleaf vs. grassy) and turf tolerance.
• Always read the label.

Weed Categories

• Broadleaf: Chickweed, henbit, dandelion, spurge, wild onion. Easy to spot.
• Grassy: Crabgrass, dallisgrass, bahiagrass, annual bluegrass. Harder to ID.

Specific Weed Controls

• Annual bluegrass: Pre-emergent mid-Sept + early Nov. Or spot-spray non-selective in spring before seeding. Wiper method works too.
• Chickweed: Pre-emergent (isoxaben) or broadleaf herbicides (2,4-D, MCPP). Safe on non-dormant grass; wait 4 mowings on new fescue.
• Wild onion/garlic: Two spring sprays (6 weeks apart) with glyphosate or broadleaf herbicide; two fall sprays at emergence. Imazaquin (Image) also works. Avoid during green-up or on new sod.

Weed ’n’ Feed Caution

Fertilizer and weed preventer timing often conflict. Warm-season grasses: fertilize at green-up, prevent weeds before. Fescue: fall granular with broadleaf killer OK if lawn damp. Read the label.

Moss

Moss indicates shade/wetness, not competition. Fix drainage, increase light, reseed. Lime/chemicals are temporary.

Henbit