Purpletop Tridens
Tridens flavus
Last reviewed: August 2026
Tridens flavus (Redtop) is a native perennial grass found across most of the United States, blooming June through August with purplish-red flower clusters that attract bees.
The USDA PLANTS Database (opens in new tab) does not flag Purpletop Tridens as toxic to livestock.
Light
full sun
Water
medium
Size
24"–48" H × 12"–24" W
Bloom
Jun, Jul, Aug
Native to
AL, AR, CT, DE and 31 more states
Pollinators
bees
Before you buy
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Redtop is a native warm-season grass that forms upright clumps with fine-textured foliage and airy seed heads. It produces delicate reddish-purple flower clusters from June through August, adding movement and seasonal interest to the landscape. This drought-tolerant grass works well in naturalized areas and prairie-style plantings.
Growing Purpletop Tridens
Grow Purpletop Tridens in full sun and medium water. Mature plants reach 24 to 48 inches tall and spread 12 to 24 inches wide. Expect low maintenance to keep it looking intentional in a front yard.
In an HOA neighborhood
Purpletop Tridens 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.
- Appears too wild and informal for typical HOA standards
- Can look unkempt when dormant in winter
- May be perceived as weedy rather than intentionally planted
Wildlife value
The flowers attract bees and other pollinators during the summer months. Seeds provide food for birds, particularly songbirds and game birds.
Common questions
- Where does Tridens flavus naturally grow?
- Tridens flavus is native to most of the United States, from the Southeast through the Great Plains and into parts of the Northeast and West Coast.
- When does Redtop grass bloom?
- Tridens flavus produces its distinctive purplish-red flower panicles from June through August during the summer growing season.
- What pollinators visit Tridens flavus?
- Bees are the primary pollinators of Redtop grass, visiting the small flowers for nectar and pollen during the blooming period.
- What growing conditions does Redtop prefer?
- Tridens flavus grows best in full sun with medium moisture but can tolerate a range of light and water conditions, making it adaptable to various sites.
- Is Purpletop Tridens toxic to livestock?
- The USDA PLANTS Database does not flag Purpletop Tridens as toxic to livestock.
- Is Purpletop Tridens HOA-friendly?
- Purpletop Tridens 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 vouchered herbarium specimen records and regional native plant society lists. Pollinator and host plant associations compiled from GBIF, iNaturalist, and published ecological literature.
Ready to grow Purpletop Tridens? Add it to your garden in Pollinator Patch to track it and get season-by-season care guidance.
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