North America Native Plant

Slender Mountain Sandwort

Botanical name: Arenaria capillaris capillaris

USDA symbol: ARCAC6

Life cycle: perennial

Habit: subshrub

Native status: Native to Alaska âš˜ Native to Canada  

Synonyms: Arenaria capillaris Poir. var. nardifolia (Ledeb.) Regel (ARCAN)  âš˜  Arenaria nardifolia Ledeb. (ARNA)  âš˜  Eremogone capillaris (Poir.) Fenzl (ERCA22)   

Slender Mountain Sandwort: A Tiny Arctic Gem for Specialized Gardens If you’re dreaming of bringing a piece of the Arctic wilderness to your garden, slender mountain sandwort (Arenaria capillaris capillaris) might catch your eye. This diminutive perennial is as specialized as plants get, hailing from some of the most remote ...

Slender Mountain Sandwort: A Tiny Arctic Gem for Specialized Gardens

If you’re dreaming of bringing a piece of the Arctic wilderness to your garden, slender mountain sandwort (Arenaria capillaris capillaris) might catch your eye. This diminutive perennial is as specialized as plants get, hailing from some of the most remote and challenging environments on Earth.

What is Slender Mountain Sandwort?

Slender mountain sandwort is a native perennial forb that belongs to the sandwort family. As a forb herb, it’s a vascular plant without significant woody tissue—think of it as nature’s version of a living carpet designed for extreme conditions. This hardy little plant has adapted to thrive where few others can survive.

You might also encounter this plant listed under several scientific synonyms, including Arenaria capillaris Poir. var. nardifolia, Arenaria nardifolia, or Eremogone capillaris, which can make identification a bit tricky for plant enthusiasts.

Where Does It Call Home?

This arctic specialist is native to Alaska and Canada, specifically thriving in Alaska, Yukon, and the Northwest Territories. It’s perfectly at home in the harsh, unforgiving landscapes of the far north, where summer growing seasons are brief and winters are long and brutal.

Should You Grow Slender Mountain Sandwort?

Here’s where things get interesting—and challenging. While slender mountain sandwort is undeniably a fascinating native plant, it’s not your typical garden center find, and for good reason.

The Reality Check

This plant is essentially an arctic specialist that has evolved for conditions most gardeners will never encounter. Unless you live in the far northern regions where it naturally occurs, recreating its preferred growing conditions will be extremely difficult, if not impossible.

Wetland Preferences Tell a Story

The plant’s wetland status varies by region, which gives us clues about its adaptability:

  • In Alaska: Obligate Upland (almost never in wetlands)
  • In the Arid West: Facultative Upland (usually non-wetlands, occasionally wetlands)
  • In Western Mountains, Valleys, and Coast: Facultative Upland

This suggests the plant prefers well-drained conditions but can tolerate some moisture variation depending on the regional climate.

Growing Conditions and Care

If you’re determined to try growing this arctic beauty, here’s what you’ll need to consider:

Climate Requirements

Based on its native range, slender mountain sandwort likely thrives in USDA hardiness zones 1-4, requiring genuinely cold winters and cool summers. If you’re gardening in warmer zones, this plant simply isn’t going to work for you.

Soil and Site Conditions

Like most sandworts, this species likely prefers:

  • Extremely well-draining, sandy or gravelly soils
  • Full sun to partial shade
  • Cool, consistent moisture during the growing season
  • Protection from hot afternoon sun in marginal climates

Garden Design Possibilities

For the rare gardener in the right climate zone, slender mountain sandwort could potentially work in:

  • Specialized alpine rock gardens
  • Native plant collections focused on arctic flora
  • Botanical gardens with climate-controlled environments
  • Research or educational gardens

The Bottom Line

Slender mountain sandwort is undoubtedly a remarkable plant, perfectly adapted to one of Earth’s most challenging environments. However, it’s honestly not a practical choice for most gardeners. Its highly specialized requirements and extremely limited growing range make it more of a botanical curiosity than a garden staple.

If you’re fascinated by arctic plants but live outside their natural range, consider visiting botanical gardens that specialize in arctic flora, or focus on more adaptable native plants from your own region. Sometimes the most beautiful plants are best appreciated in their natural habitats rather than coaxed into our gardens.

For gardeners in the far north who might actually encounter this plant naturally, consider yourself lucky to witness this tiny survivor in action—and perhaps focus on protecting its natural habitat rather than trying to cultivate it elsewhere.

Wetland Status

The rule of seasoned gardeners and landscapers is to choose the "right plant for the right place" matching plants to their ideal growing conditions, so they'll thrive with less work and fewer inputs. But the simplicity of this catchphrase conceals how tricky plant selection is. While tags list watering requirements, there's more to the story.

Knowing a plant's wetland status can simplify the process by revealing the interaction between plants, water, and soil. Surprisingly, many popular landscape plants are wetland species! And what may be a wetland plant in one area, in another it might thrive in drier conditions. Also, it helps you make smarter gardening choices and grow healthy plants with less care and feeding, saving you time, frustration, and money while producing an attractive garden with greater ecological benefits.

Regions
Status
Moisture Conditions

Alaska

UPL

Obligate Upland - Plants with this status almost never occurs in wetlands

Arid West

FACU

Facultative Upland - Plants with this status usually occurs in non-wetlands but may occur in wetlands

Western Mountains, Valleys, and Coast

FACU

Facultative Upland - Plants with this status usually occurs in non-wetlands but may occur in wetlands

Slender Mountain Sandwort

Classification

Group

Dicot

Kingdom

Plantae - Plants

Subkingdom

Tracheobionta - Vascular plants

Superdivision

Spermatophyta - Seed plants

Division

Magnoliophyta - Flowering plants

Subdivision
Class

Magnoliopsida - Dicotyledons

Subclass

Caryophyllidae

Order

Caryophyllales

Family

Caryophyllaceae Juss. - Pink family

Genus

Arenaria L. - sandwort

Species

Arenaria capillaris Poir. - slender mountain sandwort

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