North America Native Plant

Groundcover Milkvetch

Botanical name: Astragalus humistratus var. sonorae

USDA symbol: ASHUS

Life cycle: perennial

Habit: forb

Native status: Native to the lower 48 states  

Groundcover Milkvetch: A Low-Key Native for Desert Gardens If you’re looking for a truly local plant that flies under the radar, groundcover milkvetch (Astragalus humistratus var. sonorae) might just be your hidden gem. This unassuming native perennial is one of those plants that doesn’t make headlines but quietly does its ...

Groundcover Milkvetch: A Low-Key Native for Desert Gardens

If you’re looking for a truly local plant that flies under the radar, groundcover milkvetch (Astragalus humistratus var. sonorae) might just be your hidden gem. This unassuming native perennial is one of those plants that doesn’t make headlines but quietly does its job in the landscape – assuming you can find it, that is!

Where Does Groundcover Milkvetch Call Home?

This particular variety of milkvetch is native to the southwestern United States, specifically found in Arizona and New Mexico. It’s perfectly at home in the Sonoran Desert region, where it has adapted to the unique challenges of desert living over countless generations.

The Mystery Plant Challenge

Here’s where things get interesting (and a bit frustrating): groundcover milkvetch is something of an enigma in the gardening world. While we know it exists and where it comes from, detailed cultivation information is surprisingly scarce. This isn’t unusual for some of our more specialized native plants, especially those that haven’t made the jump to mainstream horticulture.

Why Consider This Desert Native?

Despite the limited information available, there are some compelling reasons to consider groundcover milkvetch for your native garden:

  • True native credentials: This plant belongs in Arizona and New Mexico landscapes
  • Perennial staying power: Once established, it should return year after year
  • Nitrogen fixing benefits: Like other milkvetches, it likely helps improve soil fertility
  • Low-profile appeal: Perfect for gardeners who prefer subtle, understated plants
  • Desert adapted: Built to handle tough southwestern conditions

Growing Groundcover Milkvetch (The Best Guess Edition)

Since specific growing instructions for this variety are hard to come by, here’s what we can reasonably assume based on its native habitat and family characteristics:

Preferred Conditions

  • Sunlight: Likely full sun to partial shade
  • Soil: Well-draining, probably sandy or rocky soils
  • Water: Low to moderate water needs once established
  • Climate: Adapted to hot, dry conditions with cool winters

The Reality Check

Here’s the honest truth: finding this plant in nurseries or seed catalogs might be like searching for a needle in a haystack. Many specialized native varieties simply aren’t commercially available, especially those with limited distribution ranges.

Is This Plant Right for Your Garden?

Groundcover milkvetch might be perfect for you if:

  • You’re a native plant purist who wants truly local species
  • You enjoy the challenge of growing uncommon plants
  • You have connections to native plant societies or seed exchanges
  • You’re working on habitat restoration in its native range

However, you might want to look elsewhere if:

  • You prefer plants with readily available growing information
  • You want something you can easily purchase and plant this weekend
  • You’re new to native gardening and want more foolproof options

Alternative Native Milkvetches

If groundcover milkvetch proves too elusive, consider other native Astragalus species that might be more available in your area. Many milkvetches share similar benefits and growing requirements while being easier to source and grow.

The Bottom Line

Groundcover milkvetch represents one of those fascinating but frustrating aspects of native plant gardening – sometimes the most interesting plants are the hardest to learn about and grow. While it’s certainly worth pursuing if you’re up for the challenge, don’t feel bad about starting with more accessible natives and working your way up to the mysterious ones.

After all, every native plant garden is a journey, and sometimes the most rewarding destinations are the ones that require a little extra effort to reach!

Groundcover 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 humistratus A. Gray - groundcover milkvetch

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