North America Non-native Plant

Astragalus Stevenianus

Botanical name: Astragalus stevenianus

USDA symbol: ASST21

Native status: Not native but doesn't reproduce and persist in the wild

Astragalus stevenianus: The Mystery Milk-Vetch You Probably Can’t (and Shouldn’t Try to) Grow If you’ve stumbled upon the name Astragalus stevenianus in your quest for unique native plants, you’ve discovered one of botany’s more elusive characters. This particular milk-vetch is so rare and poorly documented that even seasoned native plant ...

Astragalus stevenianus: The Mystery Milk-Vetch You Probably Can’t (and Shouldn’t Try to) Grow

If you’ve stumbled upon the name Astragalus stevenianus in your quest for unique native plants, you’ve discovered one of botany’s more elusive characters. This particular milk-vetch is so rare and poorly documented that even seasoned native plant enthusiasts would be hard-pressed to tell you much about it.

What We Know (Which Isn’t Much)

Astragalus stevenianus belongs to the vast Astragalus genus, commonly known as milk-vetches or locoweed. With over 3,000 species worldwide, this genus is one of the largest in the plant kingdom. However, our particular species appears to be either extremely rare, geographically restricted, or possibly even a taxonomic mystery that hasn’t been fully resolved by botanists.

The species name stevenianus suggests it was named after someone called Steven, likely a botanist or collector, and the limited references point to origins in Central Asian regions, possibly Kazakhstan or surrounding areas.

Why You Won’t Find This at Your Local Nursery

Here’s the thing about Astragalus stevenianus – it’s essentially unavailable in cultivation. There are several reasons why this plant remains a gardening ghost:

  • Extremely limited distribution in the wild
  • No established cultivation practices
  • Possibly adapted to very specific soil and climate conditions
  • Unknown seed viability and germination requirements
  • Potential conservation concerns due to rarity

Better Alternatives for Your Native Garden

Instead of chasing botanical unicorns, consider these well-established native Astragalus species that actually thrive in cultivation:

  • Canadian Milk-Vetch (Astragalus canadensis) – A robust perennial perfect for prairie gardens
  • Purple Milk-Vetch (Astragalus agrestis) – Lovely purple flowers and great for pollinators
  • Ground Plum (Astragalus crassicarpus) – Low-growing with interesting inflated seed pods
  • Woolly Locoweed (Astragalus mollissimus) – Silvery foliage adds texture to dry gardens

The Conservation Angle

When a plant species is this obscure, it often signals potential conservation concerns. Rather than attempting to source Astragalus stevenianus (which would likely be impossible anyway), consider supporting native plant conservation by:

  • Growing well-documented native alternatives
  • Supporting botanical gardens and research institutions
  • Participating in citizen science projects that help document rare plants
  • Choosing responsibly sourced native plants for your garden

The Takeaway

Astragalus stevenianus serves as a reminder that not every plant species is meant for our gardens – and that’s perfectly okay. Some plants are meant to remain wild, rare, and mysterious. As responsible native gardeners, our role is to celebrate and cultivate the plants that are both ecologically beneficial and horticulturally viable.

Instead of pursuing botanical ghosts, focus your energy on the many wonderful, available native plants that will thrive in your garden while supporting local ecosystems. Your local pollinators will thank you, and you’ll have much better success growing plants that actually want to be grown!

Astragalus Stevenianus

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 stevenianus DC.

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