North America Native Plant

Bishop’s Milkvetch

Botanical name: Astragalus episcopus var. lancearius

USDA symbol: ASEPL

Life cycle: perennial

Habit: forb

Native status: Native to the lower 48 states  

Synonyms: Astragalus lancearius A. Gray (ASLA7)   

Bishop’s Milkvetch: A Hidden Gem for Desert Gardens If you’re looking to create an authentic southwestern landscape that supports local wildlife while conserving water, bishop’s milkvetch (Astragalus episcopus var. lancearius) might just be the unsung hero your garden needs. This charming native perennial brings both beauty and ecological value to ...

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 ⚘

Bishop’s Milkvetch: A Hidden Gem for Desert Gardens

If you’re looking to create an authentic southwestern landscape that supports local wildlife while conserving water, bishop’s milkvetch (Astragalus episcopus var. lancearius) might just be the unsung hero your garden needs. This charming native perennial brings both beauty and ecological value to arid landscapes, though it does require some special consideration due to its conservation status.

What Makes Bishop’s Milkvetch Special

Bishop’s milkvetch is a true southwestern native, naturally occurring in Arizona and Utah where it has adapted to thrive in challenging desert conditions. Also known by its synonym Astragalus lancearius, this hardy perennial has evolved to make the most of limited water resources while providing essential habitat for native pollinators.

The plant produces delicate purple to pink pea-like flowers arranged in attractive clusters, creating a lovely contrast against its silvery-green foliage. The compound leaves feature narrow leaflets that help minimize water loss – a perfect example of form following function in nature’s design.

Where Does It Grow?

You’ll find bishop’s milkvetch naturally growing in Arizona and Utah, where it has carved out its niche in desert and semi-desert environments. This limited geographic distribution makes it a true regional specialist, perfectly adapted to the unique conditions of the southwestern United States.

A Note About Conservation

Before we dive into growing tips, it’s important to mention that bishop’s milkvetch has a Global Conservation Status that suggests it may face some population pressures in the wild. If you’re interested in adding this plant to your garden, please ensure you source it from reputable native plant nurseries that propagate their stock responsibly rather than collecting from wild populations.

Growing Bishop’s Milkvetch Successfully

The good news is that once established, bishop’s milkvetch is remarkably low-maintenance – after all, it’s designed to thrive in some pretty tough conditions!

Ideal Growing Conditions

  • Sunlight: Full sun is essential for healthy growth and flowering
  • Soil: Well-draining sandy or rocky soil is crucial – this plant cannot tolerate wet feet
  • Water: Drought tolerant once established, requiring minimal supplemental watering
  • Climate: Hardy in USDA zones 4-8, perfect for high desert conditions

Perfect Garden Companions

Bishop’s milkvetch works beautifully in several garden styles:

  • Desert and xeriscape gardens where its drought tolerance shines
  • Rock gardens where it can nestle between stones
  • Native plant gardens focused on regional flora
  • Pollinator gardens in arid regions

Its low-growing habit makes it an excellent ground cover or accent plant, and it pairs wonderfully with other southwestern natives like desert marigold, brittlebush, and various cacti.

Planting and Care Tips

The key to success with bishop’s milkvetch is thinking like the desert – less is often more!

  • Plant in spring after the last frost when soil temperatures are warming
  • Ensure excellent drainage by amending heavy soils with sand and gravel
  • Water sparingly during establishment, then reduce to minimal amounts
  • Avoid fertilizing – desert plants prefer lean soils
  • Be patient with germination if growing from seed, as legume seeds often have hard coats

Benefits for Wildlife

Like many members of the legume family, bishop’s milkvetch is a pollinator magnet. Its flowers attract native bees and other small pollinators that have co-evolved with southwestern flora. By planting this species, you’re not just adding beauty to your landscape – you’re supporting the intricate web of life that makes desert ecosystems so fascinating.

Is Bishop’s Milkvetch Right for Your Garden?

If you live in the Southwest and want to create a water-wise landscape that celebrates your region’s natural heritage, bishop’s milkvetch could be a wonderful addition. Just remember to source it responsibly and give it the well-draining conditions it craves. With the right care, this little native will reward you with years of delicate blooms and the satisfaction of supporting local wildlife – all while barely touching your water bill!

Bishop’s 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 episcopus S. Watson - bishop's milkvetch

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