Crabgrass
Digitaria sanguinalis · Warm-season, Annual, C4
Grass Family
Poaceae, Panicoideae
Grass Category
Invasive/Weed Grass
Variety / Cultivar
Large/Hairy Crabgrass (standard wild type)
Hardiness Zones
USDA Zones 2-11; survives as seeds in soil during winter; requires soil temps >55°F to germinate.
About This Grass
A coarse, pale green weed that grows in unsightly clumps. It starts low to the ground in a starfish pattern before sending up branched finger-like seed heads. It thrives in high heat and dies after the first frost.
Blade Characteristics
Coarse blades (5-10mm wide), distinctly hairy on leaf sheaths and blades. Vernation is rolled. The tip is pointed. Ligule is large and membranous. Auricles are absent.
Root System
Fibrous and shallow, but aggressive. Nodes on stems can root when they touch soil, allowing the plant to spread horizontally and anchor firmly.
Growing Information
Origin Region
Native to Europe and North Africa; naturalized worldwide in temperate and tropical zones.
Growth Habit
Bunch-type or prostrate mats; shoots root at lower nodes (decumbent).
Sunlight & Water Needs
Full sun (requires at least 6-8 hours), highly drought-tolerant, enjoys frequent watering but survives in poor, dry soil.
Mowing & Maintenance
Often mown at lawn height (2-4 inches), but it adapts by producing seed heads very low to the ground to survive mowing. Very low maintenance as it is a weed.
Special Characteristics
Extreme heat tolerance, rapid growth in summer, high seed production (up to 150,000 seeds per plant), excellent salt tolerance, poor shade tolerance.
Ecological Information
Introduced/Invasive in turf; seeds provide food for small birds/rodents; stabilizes bare soil rapidly but competes aggressively with desirable turf grasses like Kentucky Bluegrass.