North America Native Plant

Needle Mountain Milkvetch

Botanical name: Astragalus eurylobus

USDA symbol: ASEU3

Life cycle: perennial

Habit: forb

Native status: Native to the lower 48 states  

Synonyms: Astragalus tephrodes A. Gray var. eurylobus Barneby (ASTEE)   

Needle Mountain Milkvetch: A Rare Desert Gem Worth Protecting If you’re passionate about native plants and conservation, you might want to know about Needle Mountain milkvetch (Astragalus eurylobus), one of the Southwest’s most imperiled wildflowers. This little-known perennial legume is a true rarity in the gardening world – and that’s ...

Rare plant alert!

Region: Conservation status by state

Status: S2: Status is uncertain but is somewhere between the following rankings: 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) ⚘

Needle Mountain Milkvetch: A Rare Desert Gem Worth Protecting

If you’re passionate about native plants and conservation, you might want to know about Needle Mountain milkvetch (Astragalus eurylobus), one of the Southwest’s most imperiled wildflowers. This little-known perennial legume is a true rarity in the gardening world – and that’s exactly why it deserves our attention.

What Makes Needle Mountain Milkvetch Special?

Needle Mountain milkvetch is a native perennial that calls the arid landscapes of Arizona and Nevada home. As a member of the legume family, it produces the characteristic pea-like flowers that make Astragalus species so distinctive. The blooms typically appear in shades of purple to pink, creating lovely clusters against the plant’s compound leaves.

This plant is found exclusively in Arizona and Nevada, making it a true regional specialty for southwestern native plant enthusiasts.

Why You Should (Carefully) Consider Growing It

Here’s where things get serious: Needle Mountain milkvetch has a Global Conservation Status of S2, meaning it’s considered Imperiled. This classification indicates the species faces extreme rarity with typically only 6 to 20 occurrences remaining in the wild, or just 1,000 to 3,000 individual plants total.

Important Conservation Note: If you’re interested in growing this rare beauty, only source plants or seeds from reputable native plant nurseries that use responsibly collected material. Never collect from wild populations.

Garden Role and Design Applications

When grown responsibly, Needle Mountain milkvetch can play several valuable roles in your landscape:

  • Perfect for authentic desert and xeriscape gardens
  • Excellent choice for native plant conservation gardens
  • Suitable for rock gardens and naturalized areas
  • Ideal for educational or demonstration plantings about regional flora

Growing Conditions and Care

Like most desert natives, Needle Mountain milkvetch thrives in conditions that might challenge other garden plants:

  • Sunlight: Full sun exposure
  • Soil: Well-draining, arid soils (avoid heavy clay or constantly moist conditions)
  • Water: Drought tolerant once established; minimal supplemental watering needed
  • Climate: Best suited for USDA hardiness zones 7-10

Pollinator and Wildlife Benefits

As a native legume, Needle Mountain milkvetch offers valuable ecosystem services. Its pea-like flowers attract native bees and other pollinators, while the plant’s nitrogen-fixing capabilities help improve soil health naturally. These characteristics make it particularly valuable for supporting local wildlife populations.

Planting and Care Tips

Growing rare plants requires extra thoughtfulness:

  • Source only from ethical, conservation-minded nurseries
  • Plant in fall or early spring for best establishment
  • Avoid overwatering – this desert native prefers dry conditions
  • Be patient with establishment; rare plants often grow slowly
  • Consider growing it as part of a broader native plant conservation effort

The Bottom Line

Needle Mountain milkvetch represents both an opportunity and a responsibility. While it can be a meaningful addition to conservation-minded desert gardens, its imperiled status means we must approach it with respect and caution. If you choose to grow this rare native, you’re not just adding a plant to your garden – you’re participating in conservation efforts for one of the Southwest’s most vulnerable species.

Remember: with great rarity comes great responsibility. Always source ethically, never collect from the wild, and consider this plant as part of a larger commitment to native plant conservation.

Needle Mountain 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 eurylobus (Barneby) Barneby - Needle Mountain milkvetch

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