North America Native Plant

Purple Reedgrass

Botanical name: Calamagrostis purpurascens var. purpurascens

USDA symbol: CAPUP7

Life cycle: perennial

Habit: grass

Native status: Native to Alaska ⚘ Native to Canada ⚘ Native to Greenland ⚘ Native to the lower 48 states  

Synonyms: Calamagrostis lepageana Louis-Marie (CALE21)  ⚘  Calamagrostis maltei (Polunin) Á. Löve & D. Löve (CAMA27)  ⚘  Calamagrostis purpurascens R. Br. ssp. maltei (Polunin) A.E. Porsild (CAPUM)  ⚘  Calamagrostis purpurascens R. Br. var. maltei Polunin (CAPUM2)  ⚘  Calamagrostis yukonensis Nash (CAYU2)  ⚘  Deschampsia congestiformis Booth (DECO)   

Purple Reedgrass: A Hardy Native Grass for Cool Climate Gardens If you’re looking for a resilient native grass that can handle tough conditions while adding subtle beauty to your landscape, purple reedgrass (Calamagrostis purpurascens var. purpurascens) might be exactly what you need. This hardy perennial grass brings a touch of ...

Purple Reedgrass: A Hardy Native Grass for Cool Climate Gardens

If you’re looking for a resilient native grass that can handle tough conditions while adding subtle beauty to your landscape, purple reedgrass (Calamagrostis purpurascens var. purpurascens) might be exactly what you need. This hardy perennial grass brings a touch of the wild northern landscapes right to your backyard.

What is Purple Reedgrass?

Purple reedgrass is a perennial grass that belongs to the graminoid family, which includes grasses, sedges, and rushes. True to its name, this attractive grass produces flower heads with distinctive purple tinges that catch the light beautifully. As a clump-forming grass, it creates dense, neat mounds that work wonderfully as accent plants or ground cover in appropriate settings.

Where Does Purple Reedgrass Come From?

This grass is a true North American native with an impressive range. Purple reedgrass naturally grows across Alaska, throughout much of Canada (including Alberta, British Columbia, Manitoba, Ontario, Quebec, Saskatchewan, Yukon, Northwest Territories, Nunavut, and Newfoundland), and extends into Greenland. In the lower 48 states, you can find it growing wild in California, Colorado, Idaho, Minnesota, Montana, Nevada, New Mexico, Oregon, South Dakota, Utah, Washington, and Wyoming.

Why Grow Purple Reedgrass?

There are several compelling reasons to consider adding this native grass to your landscape:

  • Extremely hardy: This grass thrives in USDA hardiness zones 2-7, making it perfect for gardeners in cooler climates
  • Low maintenance: Once established, purple reedgrass is quite drought tolerant and requires minimal care
  • Native benefits: As a native plant, it supports local ecosystems and requires fewer resources than non-native alternatives
  • Attractive appearance: The purple-tinged flower heads add subtle color and texture to garden designs
  • Versatile use: Works well in rock gardens, alpine gardens, naturalized areas, and as erosion control

Where to Use Purple Reedgrass in Your Landscape

This adaptable grass shines in several garden settings. It’s particularly well-suited for native plant gardens where you want to recreate natural mountain or northern prairie landscapes. Rock gardens and alpine gardens are ideal spots, as the grass naturally grows in these challenging conditions. You can also use it in naturalized areas where you want low-maintenance ground cover, or on slopes where its root system can help prevent erosion.

Growing Conditions

Purple reedgrass prefers cool, moist conditions that mimic its native habitat. Plant it in areas with well-drained soil, as it doesn’t tolerate waterlogged conditions. The grass performs best in full sun to partial shade, making it quite flexible for different garden locations. While it appreciates consistent moisture when getting established, it becomes quite drought tolerant once its root system develops.

Planting and Care Tips

Getting purple reedgrass established is relatively straightforward:

  • Planting time: Spring or early fall are the best times to plant
  • Soil preparation: Ensure good drainage; amend heavy clay soils with compost if needed
  • Watering: Keep consistently moist the first growing season, then reduce watering as the plant establishes
  • Maintenance: Cut back in late winter or early spring before new growth begins
  • Fertilizing: Generally unnecessary; native grasses typically thrive in average soils

Is Purple Reedgrass Right for Your Garden?

Purple reedgrass is an excellent choice for gardeners in cooler climates who want to incorporate native plants into their landscape. It’s particularly valuable if you’re creating a naturalized garden, need erosion control on slopes, or want a low-maintenance grass that can handle challenging conditions. However, gardeners in hot, humid climates or those looking for a showstopper ornamental grass might want to consider other options more suited to their conditions.

This hardy native grass proves that sometimes the best garden plants are the ones that have been thriving in your region for thousands of years. Purple reedgrass brings a piece of wild northern beauty to cultivated spaces while supporting local ecosystems – what more could you ask for in a garden plant?

Purple Reedgrass

Classification

Group

Monocot

Kingdom

Plantae - Plants

Subkingdom

Tracheobionta - Vascular plants

Superdivision

Spermatophyta - Seed plants

Division

Magnoliophyta - Flowering plants

Subdivision
Class

Liliopsida - Monocotyledons

Subclass

Commelinidae

Order

Cyperales

Family

Poaceae Barnhart - Grass family

Genus

Calamagrostis Adans. - reedgrass

Species

Calamagrostis purpurascens R. Br. - purple reedgrass

Plant data source: USDA, NRCS 2025. The PLANTS Database. https://plants.usda.gov,. 2/25/2025. National Plant Data Team, Greensboro, NC USA