Crabgrass is a weedy summer annual in the grass family (Poaceae) that can spread quickly and form colonies. It develops several branching stems at the base with the lower branches tending to sprawl across the ground, while their upper branches are more erect. It prefers full sun to part sun in moist to dry clay loams but is very adaptable to poor soils. It has spread to nearly every state in the country. U se a pre-emergence herbicide in late winter or early spring to prevent germination of seed. These products often need rainfall or irrigation to activate them so time your application wisely. Remove any plants that do germinate early in the season as it becomes more difficult at the roots take hold of the soil. Mulching garden beds can slow germination. It is killed off by frost. In lawn situations, keep turfgrass as healthy as possible so it has a dense canopy that will outcompete crabgrass. Insects, Diseases, and Other Plant Problems: No significant problems.
Curated pairwise relationships between this plant and others in the library — who feeds
whom, who competes, who confuses the pests. Green reads as a good pairing, red as one to avoid.
No curated interactions recorded for this species yet.
Also noted by NC State
Related species the NC State Plant Toolbox flags for this plant — look-alikes to tell
apart, and plants that play a similar role in a planting. Ones we carry in the library are linked.
Full sun (6 or more hours of direct sunlight a day) | Partial Shade (Direct sunlight only part of the day, 2-6 hours)
Soil texture
Clay; Loam (Silt); Sand
Soil pH
Acid (<6.0); Neutral (6.0-8.0)
Soil drainage
Good Drainage | Occasionally Wet
Available space
12 inches-3 feet
NC region
Coastal; Mountains; Piedmont
Growth rate
Rapid
Maintenance
High
Form & Appearance
Habit / form
Horizontal; Prostrate
Texture
Medium
Leaf color
Green
Leaf type
Sheath; Simple
Leaf arrangement
Alternate
Leaf shape
Linear
Leaf margin
Entire
Leaf size
3-6 inches long, < 1 inch wide
Hairs present
Yes
Leaf detail
The leaf blades are up to 6" long and nearly ½" across and are dull light green. They can be slightly curly along the margins and are often hairy toward the base.
Flower color
Green
Flower form
Insignificant; Panicle; Raceme
Flower size
< 1 inch
Flower detail
There are many pairs of one-flowered spikelets along the length of each raceme that can be up to 8 inches long. They occur along one side of the flattened stalk mid-summer to early fall.
Bloom time
Fall; Summer
Fruit type
Caryopsis
Fruit size
< 1 inch long, < 1 inch wide
Fruit detail
Produces many seeds remove plants before they set seed to reduce the population the following growing season.
Stem detail
Stems are prostrate, spreading, and rooting at nodes. They can be branched at nodes.
Wildlife & Ecology
Native status
Non-native
Origin
Eurasia
Distribution
Wide distribution worldwide.
Food & Medicine
Edible parts
Nuts
Harvest time
Fall; Summer
Fruit type
Caryopsis
Edibility
The grain is edible and nutritious
Uses (ethnobotany)
Used as a hand-forged grain in the past.
Landscape Use
Landscape location
Lawn
Garden tags
#horizontal #summer annual weed #warm season weed #high maintenance #full sun tolerant #aggressive #upright form #annual #cpp #weedy #poor soil tolerant