North America Native Plant

Silverleaf Milkvetch

Botanical name: Astragalus argophyllus var. panguicensis

USDA symbol: ASARP

Life cycle: perennial

Habit: forb

Native status: Native to the lower 48 states  

Synonyms: Astragalus panguicensis (M.E. Jones) M.E. Jones (ASPA29)   

Silverleaf Milkvetch: A Hidden Gem for Desert Gardens Meet the silverleaf milkvetch (Astragalus argophyllus var. panguicensis), a tough little perennial that’s perfectly at home in the arid landscapes of the American Southwest. While it might not be the flashiest plant in your garden center, this native beauty has some serious ...

Rare plant alert!

Region: Conservation status by state

Status: S5T3T4: 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. ⚘ Subspecies or varieties is apparently secure: Uncommon but not rare, and usually widespread. Possibly cause for longterm concern. Typically more than 100 occurrences in the region or more than 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. ⚘

Silverleaf Milkvetch: A Hidden Gem for Desert Gardens

Meet the silverleaf milkvetch (Astragalus argophyllus var. panguicensis), a tough little perennial that’s perfectly at home in the arid landscapes of the American Southwest. While it might not be the flashiest plant in your garden center, this native beauty has some serious staying power and a quiet charm that grows on you.

What Makes Silverleaf Milkvetch Special?

This hardy perennial is a true native of the lower 48 states, specifically calling Arizona and Utah home. As a member of the legume family, silverleaf milkvetch has that classic pea-like flower structure, producing small white to cream-colored blooms that may be modest in size but are rich in character. The plant gets its silverleaf moniker from its distinctive grayish-green foliage that has a silvery cast – a natural adaptation that helps it reflect harsh desert sunlight.

Where Does It Grow?

Silverleaf milkvetch has carved out its niche in the desert regions of Arizona and Utah, where it’s learned to thrive in conditions that would challenge many other plants. You’ll find it growing naturally in areas with well-draining soils and plenty of sunshine.

Why Grow Silverleaf Milkvetch?

Here are some compelling reasons to consider this native for your landscape:

  • Water-wise wonder: Once established, this plant is incredibly drought-tolerant, making it perfect for xeriscaping projects
  • Native credentials: Supporting local ecosystems by choosing native plants is always a win
  • Pollinator friendly: Those small flowers attract native bees and other beneficial insects
  • Low maintenance: Perfect for gardeners who want beauty without the fuss
  • Cold hardy: Suitable for USDA zones 4-8, so it can handle temperature extremes

Growing Silverleaf Milkvetch Successfully

The good news is that silverleaf milkvetch isn’t particularly demanding – it’s adapted to tough conditions, after all. Here’s how to give it the best start:

Location and Soil: Choose a spot with full sun and excellent drainage. This plant absolutely cannot tolerate soggy conditions, so if your soil tends to hold water, consider raised beds or adding plenty of gravel and sand to improve drainage.

Planting: Spring is typically the best time to plant, giving the roots time to establish before extreme weather hits. Space plants appropriately for their mature size, though specific dimensions aren’t well-documented for this variety.

Watering: Here’s where many gardeners go wrong with desert natives – less is definitely more. Water deeply but infrequently during the first growing season to help establish roots, then back off significantly. Mature plants should rarely, if ever, need supplemental water in their native range.

A Word of Caution

Like many specialized native plants, silverleaf milkvetch can be challenging to find in typical nurseries. If you do locate seeds or plants, make sure they’re from reputable sources that practice responsible collection methods. This helps ensure you’re not inadvertently impacting wild populations.

Is This Plant Right for Your Garden?

Silverleaf milkvetch is ideal if you’re creating a native desert garden, working on a xeriscaping project, or simply want to support local wildlife with indigenous plants. It’s particularly well-suited for gardeners in Arizona and Utah who want to work with their natural climate rather than against it.

However, if you’re looking for showy flowers or lush foliage, this might not be your plant. Its beauty lies in its subtle silvery leaves and ecological value rather than dramatic visual impact.

The Bottom Line

Silverleaf milkvetch represents what’s wonderful about native gardening – plants that are perfectly adapted to their environment and require minimal input from us. While it may not be the easiest plant to source, it rewards patient gardeners with years of reliable performance and the satisfaction of supporting local ecosystems. For desert gardeners looking to expand their native plant palette, this tough little perennial deserves consideration.

Silverleaf 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 argophyllus Nutt. - silverleaf milkvetch

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