Lawn Weed Identification Guide: Common Annual & Perennial Weeds

Weeds reveal soil conditions and require different strategies. Annuals (shallow roots, one season) vs. perennials (deep roots, return yearly).

Common Annual Weeds

• Chickweed, crabgrass, ragweed, spotted spurge, knotweed, annual bluegrass.

Common Perennial Weeds

• Clover, nettle, dandelion, plantain, mouse-ear chickweed, ground ivy (creeping charlie).

Key Identification Features

• Dandelion: Deep taproot; fluffy seedheads.
• Ragweed: Fern-like foliage; summer; allergy trigger.
• Crabgrass: Low, spreading; reddish-purple stems; seedheads below mow height.
• Spotted spurge: Red-purple leaf center; milky sap (rash risk); pulls easily when moist.
• Chickweed: Mat-forming; star-shaped white flowers; cool/moist. Mouse-ear = hairy, perennial, heat-tolerant.
• White clover: Creeping runners; white blooms; fixes nitrogen → indicates low fertility.
• Nettle: Hairy; stinging varieties; aggressive creeping roots.
• Broadleaf plantain: Broad veined leaves; smothers grass; needs thick turf to suppress.
• Knotweed: Dry, compacted soil; wiry mat; blue-green leaves; small white flowers; no milky sap; aeration reduces seeds.
• Ground ivy: Round scalloped leaves; square stems; purple flowers; tough in shade/moisture.
• Annual bluegrass: Bright green; cool/moist; white seedheads; dies in heat.

Soil type and appearance together pinpoint the weed.