North America Native Plant

Mertens’ Oxytrope

Botanical name: Oxytropis mertensiana

USDA symbol: OXME2

Life cycle: perennial

Habit: forb

Native status: Native to Alaska âš˜ Native to Canada  

Mertens’ Oxytrope: An Arctic Beauty for the Most Adventurous Gardeners If you’re looking for a plant that laughs in the face of winter and thrives where most other plants would simply give up, meet Mertens’ oxytrope (Oxytropis mertensiana). This hardy little perennial is the botanical equivalent of a polar bear ...

Mertens’ Oxytrope: An Arctic Beauty for the Most Adventurous Gardeners

If you’re looking for a plant that laughs in the face of winter and thrives where most other plants would simply give up, meet Mertens’ oxytrope (Oxytropis mertensiana). This hardy little perennial is the botanical equivalent of a polar bear – perfectly at home in some of the coldest places on Earth, but not exactly what you’d call a backyard garden regular.

What Is Mertens’ Oxytrope?

Mertens’ oxytrope is a native perennial forb that belongs to the legume family. As a forb, it’s essentially an herbaceous plant without woody stems – think of it as nature’s version of a tough little ground-hugger that knows how to survive in extreme conditions. This plant forms low, cushion-like mounds that stay close to the ground, which is exactly the smart strategy you’d expect from something that calls the Arctic home.

Where Does It Call Home?

This cold-loving native has a pretty exclusive address list – you’ll find it naturally occurring in Alaska and Canada’s Yukon Territory. It’s perfectly adapted to arctic and subarctic conditions, thriving in places where mild weather means it’s only -20°F outside.

Why You Might (Or Might Not) Want This Plant

Let’s be honest – Mertens’ oxytrope isn’t for everyone. In fact, it’s really only for gardeners in extremely cold climates (USDA hardiness zones 1-3) who are looking for authentic native plants and don’t mind a serious gardening challenge.

The Good News:

  • Produces charming purple to violet pea-like flowers arranged in dense clusters
  • Attracts cold-adapted native bees and other specialized pollinators
  • Extremely hardy – can handle temperatures that would make a penguin shiver
  • Perfect for authentic arctic or subarctic native plant gardens
  • Adds unique character to rock gardens and alpine settings

The Reality Check:

  • Nearly impossible to grow outside its native range
  • Requires specific arctic growing conditions that are hard to replicate
  • Limited availability from nurseries
  • Very slow-growing and can be finicky to establish

Growing Conditions and Care

If you’re determined to give Mertens’ oxytrope a try, here’s what this arctic native demands:

Essential Requirements:

  • Climate: USDA zones 1-3 only – this plant needs seriously cold winters
  • Sunlight: Full sun exposure
  • Soil: Extremely well-draining soil is non-negotiable
  • Moisture: Moderate moisture but never waterlogged
  • Temperature: Requires extended cold periods for proper growth

Planting and Care Tips:

  • Plant in a rock garden or raised bed to ensure excellent drainage
  • Seeds may require cold stratification to germinate properly
  • Be patient – this is not a fast-growing plant
  • Avoid fertilizing, as it’s adapted to nutrient-poor soils
  • Protect from excessive moisture, especially during dormant periods

Landscape Role and Design Ideas

In the rare garden where it can thrive, Mertens’ oxytrope works best as:

  • A specialty addition to arctic or subarctic native plant gardens
  • An authentic touch in rock gardens designed for extreme climates
  • Part of alpine plant collections
  • A conversation starter for serious cold-climate gardeners

The Bottom Line

Mertens’ oxytrope is a fascinating native plant that showcases nature’s incredible ability to adapt to extreme conditions. However, unless you’re gardening in Alaska or northern Canada, this probably isn’t the plant for you. If you’re in warmer zones and looking for native legumes with similar purple flowers, consider exploring cold-hardy native clovers or vetches that are better suited to your climate.

For those lucky enough to garden in its native range, Mertens’ oxytrope offers a unique opportunity to grow an authentic piece of arctic flora – just be prepared for a gardening adventure that’s as challenging as it is rewarding!

Mertens’ Oxytrope

Classification

Group

Dicot

Kingdom

Plantae - Plants

Subkingdom

Tracheobionta - Vascular plants

Superdivision

Spermatophyta - Seed plants

Division

Magnoliophyta - Flowering plants

Subdivision
Class

Magnoliopsida - Dicotyledons

Subclass

Rosidae

Order

Fabales

Family

Fabaceae Lindl. - Pea family

Genus

Oxytropis DC. - locoweed

Species

Oxytropis mertensiana Turcz. - Mertens' oxytrope

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