North America Native Plant

Slimstem Reedgrass

Botanical name: Calamagrostis stricta stricta var. borealis

USDA symbol: CASTB4

Life cycle: perennial

Habit: grass

Native status: Native to Alaska  

Synonyms: Calamagrostis borealis Laest. (CABO20)  âš˜  Calamagrostis neglecta (Ehrh.) G. Gaertn., B. Mey. & Scherb. ssp. borealis (Laest.) Seland. (CANEB3)  âš˜  Calamagrostis neglecta (Ehrh.) G. Gaertn., B. Mey. & Scherb. var. borealis (Laest.) Kearney (CANEB4)   

Slimstem Reedgrass: A Hardy Northern Native for Specialized Gardens If you’re looking for an authentic piece of Alaska’s wild landscape for your garden, slimstem reedgrass (Calamagrostis stricta stricta var. borealis) might just be the native grass you didn’t know you needed. This perennial graminoid brings a touch of the far ...

Slimstem Reedgrass: A Hardy Northern Native for Specialized Gardens

If you’re looking for an authentic piece of Alaska’s wild landscape for your garden, slimstem reedgrass (Calamagrostis stricta stricta var. borealis) might just be the native grass you didn’t know you needed. This perennial graminoid brings a touch of the far north to gardens willing to embrace its unique growing requirements.

What Is Slimstem Reedgrass?

Slimstem reedgrass is a perennial grass native exclusively to Alaska, making it one of the more geographically specialized native plants you’ll encounter. As part of the large Calamagrostis genus, this variety has earned several scientific names over the years, including Calamagrostis borealis and Calamagrostis neglecta var. borealis, reflecting botanists’ ongoing efforts to properly classify these northern grasses.

This grass belongs to the graminoid group, which includes not just true grasses but also sedges, rushes, and other grass-like plants. Its slim profile gives it the slimstem part of its common name, while reedgrass reflects its membership in this widespread and ecologically important genus.

Where Does Slimstem Reedgrass Grow?

Currently, slimstem reedgrass is documented as growing exclusively in Alaska, making it a true specialist of northern climates. This limited geographic distribution tells us a lot about its growing requirements and potential garden applications.

Should You Grow Slimstem Reedgrass?

The answer depends largely on where you garden and what you’re trying to achieve. Here are some considerations:

Reasons to Consider It:

  • Authentic native plant for Alaskan gardens
  • Likely very cold hardy given its natural range
  • Perennial nature means it returns year after year
  • Contributes to native plant biodiversity
  • May provide habitat value for northern wildlife

Potential Challenges:

  • Very limited geographic range suggests specific growing requirements
  • May not adapt well to climates outside its native range
  • Limited availability in the nursery trade
  • Specific growing conditions and care requirements are not well-documented

Growing Conditions and Care

Given slimstem reedgrass’s exclusive Alaskan heritage, it likely thrives in conditions that mirror its native habitat. While specific growing requirements for this variety aren’t well-documented, we can make educated guesses based on its geographic distribution:

  • Extremely cold tolerant (likely USDA zones 1-4)
  • Adapted to short growing seasons
  • May prefer moist to wet soils
  • Likely tolerates poor or acidic soils
  • Probably requires full to partial sun

Garden Design Applications

If you’re gardening in Alaska or similar climates, slimstem reedgrass could work well in:

  • Native plant gardens showcasing local flora
  • Naturalized areas mimicking wild grasslands
  • Rain gardens or areas with seasonal moisture
  • Mixed grass plantings for texture and movement
  • Restoration projects using indigenous species

The Bottom Line

Slimstem reedgrass is clearly a specialist plant for specialist gardens. If you’re gardening in Alaska and want to support truly local native plants, this grass deserves consideration. However, its limited range and lack of detailed cultivation information mean it’s not a beginner-friendly choice.

For gardeners outside of Alaska, you’re likely better served by other Calamagrostis species or native grasses adapted to your local conditions. Always check with local native plant societies or extension services for the best native grass recommendations for your specific area.

If you do decide to try growing slimstem reedgrass, source it responsibly from reputable native plant nurseries and be prepared for some trial and error as you learn what makes this northern beauty happy in cultivation.

Slimstem 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 stricta (Timm) Koeler - slimstem reedgrass

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