North America Native Plant

Henderson’s Milkvetch

Botanical name: Astragalus accidens var. hendersonii

USDA symbol: ASACH

Life cycle: perennial

Habit: forb

Native status: Native to the lower 48 states  

Synonyms: Astragalus pachystachys Rydb. (ASPA27)  âš˜  Astragalus watsonii Sheldon (ASWA7)   

Henderson’s Milkvetch: A Rare Pacific Coast Native Worth Growing Responsibly Meet Henderson’s milkvetch (Astragalus accidens var. hendersonii), a charming perennial wildflower that calls the Pacific Coast home. This delightful member of the pea family might not be the flashiest plant in your garden, but it brings something special to native ...

Rare plant alert!

Region: Conservation status by state

Status: S5T3: Status is uncertain but is somewhere between the following rankings: 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. ⚘ Secure: At very low or no risk of extinction in the jurisdiction due to a very extensive range, abundant populations or occurrences, with little to no concern from declines or threats. ⚘

Henderson’s Milkvetch: A Rare Pacific Coast Native Worth Growing Responsibly

Meet Henderson’s milkvetch (Astragalus accidens var. hendersonii), a charming perennial wildflower that calls the Pacific Coast home. This delightful member of the pea family might not be the flashiest plant in your garden, but it brings something special to native plant landscapes with its delicate purple blooms and silvery foliage.

What Makes Henderson’s Milkvetch Special?

Henderson’s milkvetch is a true West Coast native, naturally occurring in California and Oregon. As a perennial plant, it returns year after year, making it a reliable addition to your garden once established. You might also see it listed under its botanical synonyms Astragalus pachystachys or Astragalus watsonii in older references.

This native beauty grows in specific regions along the Pacific Coast, where it has adapted to local conditions over thousands of years. Its natural range spans parts of California and Oregon, making it perfectly suited for gardens in these areas.

A Word About Rarity

Here’s something important to know: Henderson’s milkvetch has a Global Conservation Status of S5T3, which indicates some level of conservation concern. While this shouldn’t discourage you from growing it, it does mean you should be thoughtful about sourcing. Always purchase plants or seeds from reputable native plant nurseries that use responsibly collected material, rather than collecting from wild populations.

Why Grow Henderson’s Milkvetch?

There are several compelling reasons to include this native in your garden:

  • Pollinator magnet: Like other members of the pea family, it produces flowers that attract native bees and other beneficial pollinators
  • Low maintenance: Once established, it’s quite drought tolerant and requires minimal care
  • Native credentials: Supporting local ecosystems by growing plants that belong there naturally
  • Unique beauty: The combination of silvery-green compound leaves and purple pea-like flowers offers subtle charm

Garden Design and Landscape Use

Henderson’s milkvetch works wonderfully in native plant gardens, xeriscape designs, and naturalized areas. It’s not a showstopper like some ornamental plants, but it fills an important niche in wildlife-friendly landscapes. Consider using it as part of a mixed native wildflower planting or in areas where you want to establish low-maintenance ground cover.

This plant is particularly well-suited for gardens that embrace a more natural, less formal aesthetic. It pairs beautifully with other Pacific Coast natives and helps create habitat for local wildlife.

Growing Conditions and Care

Henderson’s milkvetch thrives in conditions similar to its natural habitat:

  • Sunlight: Full sun to partial shade
  • Soil: Well-draining soils; avoid heavy clay or constantly moist conditions
  • Water: Drought tolerant once established, but appreciates occasional deep watering during dry spells
  • Climate: Best suited for USDA hardiness zones 7-9

Planting and Establishment Tips

Spring is typically the best time to plant Henderson’s milkvetch. If you’re starting from seed, you may need to scarify the seeds (lightly scratch the seed coat) to improve germination, as many legume seeds have hard coats.

During the first year, provide regular water to help establish a strong root system. Once established, this tough little native can handle California’s dry summers with minimal supplemental irrigation.

The Bottom Line

Henderson’s milkvetch may not be the most dramatic plant in your garden, but it offers something valuable: authentic regional character and ecological benefits. If you garden in its native range of California or Oregon, this perennial deserves consideration for its pollinator value and low-maintenance nature.

Just remember to source it responsibly from reputable native plant nurseries, and you’ll be adding a piece of Pacific Coast natural heritage to your landscape while supporting local ecosystems.

Henderson’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 accidens S. Watson - Rogue River milkvetch

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