Spike Redtop
Agrostis exarata
Last reviewed: June 2026
Agrostis exarata (Spike Redtop) is a native perennial grass found across western and central United States that blooms June through August. This adaptable grass thrives in various moisture conditions and attracts bees and beetles.
The USDA PLANTS Database (opens in new tab) does not flag Spike Redtop as toxic to livestock.
Light
full sun
Water
medium
Size
12"–40" H × 6"–24" W
Bloom
Jun, Jul, Aug
Native to
AZ, CA, CO, ID and 13 more states
Pollinators
bees, beetles
Browse plants for this ecoregion
Spike redtop is a native perennial bunch grass that forms upright clumps with narrow leaves and delicate, spike-like flower heads. It grows moderately tall and provides good texture in naturalized areas, thriving in full sun with regular watering. The grass blooms through summer months with airy seed heads that add movement to the landscape.
Growing Spike Redtop
Grow Spike Redtop in full sun and medium water. Mature plants reach 12 to 40 inches tall and spread 6 to 24 inches wide. Expect low maintenance to keep it looking intentional in a front yard.
In an HOA neighborhood
Spike Redtop takes more care to keep looking intentional in a front yard. Maintenance level: low. Consider it for backyard or mid-zone beds rather than the street edge.
Works well in: backyard only.
- Looks too wild and unmanicured for most front yard standards
- Seed heads may appear weedy to traditional landscaping expectations
- Natural bunch grass form lacks the formal appearance HOAs typically prefer
Wildlife value
This native grass supports bees and beetles during its summer blooming period. The seeds also provide food for birds and small wildlife.
Common questions
- Where does Spike Redtop naturally grow?
- Agrostis exarata is native to 17 states across the western and central United States, including Arizona, California, Colorado, Idaho, Montana, Nevada, Oregon, Utah, Washington, Wyoming, and several others.
- When does Agrostis exarata bloom?
- Spike Redtop produces flowers during the summer months from June through August.
- What pollinators visit Spike Redtop?
- This native grass attracts bees and beetles, which help with pollination during its blooming period.
- What growing conditions does Spike Redtop prefer?
- Agrostis exarata is quite adaptable, tolerating full sun to partial sun conditions and growing well in wet, medium, or dry soil moisture levels.
- Is Spike Redtop toxic to livestock?
- The USDA PLANTS Database does not flag Spike Redtop as toxic to livestock.
- Is Spike Redtop HOA-friendly?
- Spike Redtop takes more care to look intentional in a front yard. Consider it for backyard or mid-zone beds rather than the street edge.
Native range data from the USDA PLANTS Database and regional native plant society lists. Pollinator and host plant associations compiled from GBIF, iNaturalist, and published ecological literature.
Ready to grow Spike Redtop? Add it to your garden in Pollinator Patch to track it and get season-by-season care guidance.
Not sure where to start? Take the 2-minute yard quiz