Common chickweed
Stellaria media
A low-growing winter annual forming dense mats with small white star-shaped flowers.
Identification
Common chickweed is a low, prostrate to mat-forming broadleaf with small, smooth, light-green leaves that are oval to egg-shaped and pointed at the tip, arranged opposite one another along the stems. A diagnostic trait is a single line of fine hairs running down one side of the stem that switches sides at each node. The small star-shaped flowers have five white petals so deeply notched that they appear to be ten. Stems are weak and trailing, rooting where nodes touch moist soil, and the fibrous, shallow root system is easily pulled. It is distinguished from mouseear chickweed, which is densely hairy throughout rather than mostly smooth.
Symptoms & Damage
Common chickweed forms dense, low mats that smother and crowd out turfgrass, creating soft, light-green patches that disrupt color and texture and leave thin or bare spots when the weed dies back in late spring. Because it greens up and grows actively in cool weather when turf is less competitive, infestations are conspicuous in fall through spring, and the prolific seed set ensures recurring problems season after season.
Biology
Common chickweed is principally a winter annual that germinates from seed in late summer and early fall, overwinters as a low rosette or mat, and resumes growth to flower and set seed in late winter and spring before dying back as heat arrives; in cool, moist climates it can behave almost year-round. It is a prolific seeder with a very short life cycle, often flowering only four to six weeks after germination, and stems that contact the soil can root at the nodes, allowing patches to spread vegetatively as well as by seed.
Occurrence & Spread
Chickweed is a classic indicator of cool, moist, fertile conditions and thrives in shaded, poorly drained, or consistently damp areas and in compacted soils. It exploits thin or open turf, newly seeded areas, and shaded sites where the desirable stand is weak, forming dense mats during fall and spring. Cool-season conditions, overwatering or poor drainage, and gaps in the canopy all favor its rapid establishment and spread.
Favorable Conditions
Cool, moist, shaded, fertile soils; thin turf in fall/spring.
Cultural Management
Because chickweed signals a cultural problem, the most durable control is correcting the underlying conditions: improve drainage, reduce excessive moisture and shade where possible, relieve compaction, and maintain a dense, vigorous stand through proper mowing and fertility so the canopy closes over open ground. Hand-pulling is effective on small populations because the shallow, fibrous roots lift easily, but removal should be done before the rapid seed cycle replenishes the seed bank. In landscape and bed situations, mulching and cultivation also suppress establishment.
Further Reading
University extension resources — open in a new tab.
Related Reports
No published reports yet for this pest.
Reports will appear here as they are peer-reviewed and published.