North America Native Plant

Selway Mariposa Lily

Botanical name: Calochortus elegans var. selwayensis

USDA symbol: CAELS

Life cycle: perennial

Habit: forb

Native status: Native to the lower 48 states  

Synonyms: Calochortus selwayensis H. St. John (CASE18)   

Selway Mariposa Lily: A Rare Mountain Gem Worth Protecting If you’ve ever dreamed of growing a truly special native wildflower that few gardeners have even heard of, let me introduce you to the Selway mariposa lily (Calochortus elegans var. selwayensis). This enchanting perennial is like finding a hidden treasure in ...

Rare plant alert!

Region: Conservation status by state

Status: S3S4T2T3: Status is uncertain but is somewhere between the following rankings: Subspecies or variety is imperiled: Extremely rare due to factor(s) making it especially vulnerable to extinction. Typically 6 to 20 occurrences or few remaining individuals (1,000 to 3,000) ⚘ Vulnerable: Either very rare and local throughout its range, found only in a restricted range (even if abundant at some locations), or factors are making it vulnerable to extinction. Typically 21 to 100 occurrences or between 3,000 and 10,000 individuals ⚘ Subspecies or variety is vulnerable: Either very rare and local throughout its range, found only in a restricted range (even if abundant at some locations), or factors are making it vulnerable to extinction. Typically 21 to 100 occurrences or between 3,000 and 10,000 individuals. ⚘ Apparently Secure: Uncommon but not rare, and usually widespread. Possibly cause for longterm concern. Typically more than 100 occurrences in the state or more than 10,000 individuals ⚘

Selway Mariposa Lily: A Rare Mountain Gem Worth Protecting

If you’ve ever dreamed of growing a truly special native wildflower that few gardeners have even heard of, let me introduce you to the Selway mariposa lily (Calochortus elegans var. selwayensis). This enchanting perennial is like finding a hidden treasure in the world of native plants – beautiful, mysterious, and deserving of our careful attention.

What Makes the Selway Mariposa Lily Special?

The Selway mariposa lily is a distinctive variety of the elegant mariposa lily, and it’s as lovely as its name suggests. In late spring to early summer, this herbaceous perennial produces stunning three-petaled flowers that range from pristine white to soft pale pink. Each bloom features intricate markings and patterns that make every flower a small work of art. Growing from underground bulbs, these plants typically reach 8-16 inches tall and form small, graceful clumps over time.

What truly sets this plant apart, though, is its story and rarity. The Selway mariposa lily is found in a very limited area, making it a true regional endemic that connects us to the unique ecology of the northern Rocky Mountains.

Where Does It Call Home?

This native beauty has a very specific address – you’ll find it naturally occurring only in north-central Idaho and western Montana, particularly in areas around the Selway River drainage. It’s a true native of the lower 48 states, but with such a limited range that encountering one in the wild feels like discovering botanical gold.

A Word About Rarity (This Is Important!)

Here’s where things get serious, fellow gardeners. The Selway mariposa lily has a global conservation status that indicates it’s uncommon to fairly uncommon in its native range. This means we need to be extra thoughtful about how we approach growing this plant.

If you’re interested in adding this rare beauty to your garden, please – and I cannot stress this enough – only source bulbs from reputable native plant nurseries that can guarantee their plants are responsibly propagated, not wild-collected. Better yet, consider supporting conservation efforts for this species rather than growing it yourself.

Growing Conditions and Care

Should you find ethically sourced bulbs, the Selway mariposa lily has some specific preferences that mirror its mountain home:

  • Sunlight: Partial shade to full sun
  • Soil: Well-draining soil is absolutely essential – these bulbs will rot in wet conditions
  • Water: Moderate water during growing season, but requires a dry dormant period in summer
  • Hardiness: Suited for USDA zones 4-7
  • Planting time: Plant bulbs in fall, about 3-4 inches deep

Perfect Garden Companions

In the right setting, Selway mariposa lily works beautifully in:

  • Native plant gardens focused on Rocky Mountain species
  • Rock gardens with excellent drainage
  • Naturalized areas that mimic mountain meadow conditions
  • Specialized wildflower collections

Pair it with other native mountain plants like wild bergamot, lupines, or native grasses for an authentic regional look.

Benefits to Local Wildlife

When it blooms, the Selway mariposa lily attracts native bees and other pollinators who have co-evolved with mariposa lilies over thousands of years. By growing native plants like this one (responsibly!), you’re supporting the complex web of relationships that keep our ecosystems healthy.

The Bottom Line

The Selway mariposa lily is undeniably beautiful and represents an important piece of our native plant heritage. However, its rarity means that most of us should appreciate it from afar and support conservation efforts rather than trying to grow it ourselves. If you do decide to pursue growing this special plant, please commit to sourcing it responsibly and treating it with the respect its rarity deserves.

Sometimes the most loving thing we can do for a rare plant is to let it be rare – and work to protect the wild places where it continues to thrive naturally.

Selway Mariposa Lily

Classification

Group

Monocot

Kingdom

Plantae - Plants

Subkingdom

Tracheobionta - Vascular plants

Superdivision

Spermatophyta - Seed plants

Division

Magnoliophyta - Flowering plants

Subdivision
Class

Liliopsida - Monocotyledons

Subclass

Liliidae

Order

Liliales

Family

Liliaceae Juss. - Lily family

Genus

Calochortus Pursh - mariposa lily

Species

Calochortus elegans Pursh - elegant mariposa lily

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