North America Native Plant

Cliff Palace Milkvetch

Botanical name: Astragalus deterior

USDA symbol: ASDE4

Life cycle: perennial

Habit: forb

Native status: Native to the lower 48 states  

Cliff Palace Milkvetch: A Rare Colorado Native Worth Protecting Meet Cliff Palace milkvetch (Astragalus deterior), a small but mighty native wildflower that calls the rugged landscapes of Colorado home. This little-known perennial legume might not be the showiest plant in your garden, but it carries a big conservation story that ...

Rare plant alert!

Region: Conservation status by state

Status: S1S2: Status is uncertain but is somewhere between the following rankings: Critically Imperiled: Extremely rare due to factor(s) making it especially vulnerable to extinction. Typically 5 or fewer occurrences or very few remaining individuals (<1,000) ⚘ 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) ⚘

Cliff Palace Milkvetch: A Rare Colorado Native Worth Protecting

Meet Cliff Palace milkvetch (Astragalus deterior), a small but mighty native wildflower that calls the rugged landscapes of Colorado home. This little-known perennial legume might not be the showiest plant in your garden, but it carries a big conservation story that makes it truly special.

A True Colorado Native

Cliff Palace milkvetch is as Colorado as it gets – this perennial wildflower is endemic to the state, meaning you won’t find it growing naturally anywhere else in the world. It’s particularly associated with the Mesa Verde region, where ancient cliff dwellings give this plant its evocative common name.

As a native species of the lower 48 states, specifically Colorado, this milkvetch has adapted perfectly to the challenging conditions of the Colorado Plateau over thousands of years.

Why This Plant Deserves Your Attention

Here’s where things get serious: Cliff Palace milkvetch has a conservation status of S1S2, which means it’s considered critically imperiled to imperiled in its native range. In plain English? This plant is rare – really rare. That makes it both fascinating for native plant enthusiasts and important for conservation efforts.

If you’re considering growing this species, please ensure you source it responsibly from reputable native plant nurseries that propagate from ethically collected seed, never from wild-collected plants.

What Does It Look Like?

Like other members of the Astragalus genus, Cliff Palace milkvetch produces:

  • Delicate compound leaves typical of legumes
  • Purple to pink pea-like flowers that bloom in small clusters
  • A low-growing, perennial growth habit adapted to harsh conditions
  • Seed pods characteristic of the milkvetch family

Perfect Spots for Growing

This isn’t your typical garden center find, but if you can source it responsibly, Cliff Palace milkvetch works beautifully in:

  • Specialized native plant collections
  • Rock gardens that mimic Colorado’s natural landscapes
  • Xeriscaping projects focused on water conservation
  • Educational gardens highlighting rare native species

Growing Conditions and Care

Think Colorado wilderness when planning for this plant:

  • Sun: Full sun exposure
  • Soil: Well-draining, rocky or sandy soils
  • Water: Minimal once established – this plant despises wet feet
  • Climate: Suitable for USDA hardiness zones 5-7
  • Drainage: Excellent drainage is absolutely critical

Planting and Care Tips

Growing rare natives like Cliff Palace milkvetch requires patience and attention to detail:

  • Plant in spring after the last frost
  • Amend heavy soils with gravel or sand to improve drainage
  • Water sparingly – overwatering is the fastest way to lose this plant
  • Avoid fertilizers, which can harm native wildflowers
  • Be patient – establishment may take time

Supporting Pollinators and Wildlife

As a member of the legume family, Cliff Palace milkvetch offers nectar to native bees and other small pollinators. Its seeds may also provide food for wildlife, though specific benefits for this rare species aren’t well-documented.

The Bottom Line

Cliff Palace milkvetch represents something special in the native plant world – a true endemic that tells the story of Colorado’s unique landscapes. While it may be challenging to grow and even harder to find, supporting conservation efforts for rare natives like this one helps preserve biodiversity for future generations.

If you’re drawn to rare natives, consider this plant for specialized gardens, but always prioritize responsible sourcing. Sometimes the most meaningful gardening choices are the ones that help protect what’s precious and irreplaceable in our natural world.

Cliff Palace Milkvetch

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

Astragalus L. - milkvetch

Species

Astragalus deterior (Barneby) Barneby - Cliff Palace milkvetch

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