North America Native Plant

Packard’s Milkvetch

Botanical name: Astragalus cusickii var. packardiae

USDA symbol: ASCUP

Life cycle: perennial

Habit: forb

Native status: Native to the lower 48 states  

Packard’s Milkvetch: A Rare Idaho Native Worth Knowing About If you’re passionate about native plants and rare botanical treasures, you’ve probably never heard of Packard’s milkvetch (Astragalus cusickii var. packardiae). And honestly, that’s not surprising – this little-known perennial is one of those plants that flies completely under the radar, ...

Rare plant alert!

Region: Conservation status by state

Status: S5T1: Status is uncertain but is somewhere between the following rankings: Subspecies or variety is critically Imperiled: Extremely rare due to factor(s) making it especially vulnerable to extinction. Typically 5 or fewer occurrences or very few remaining individuals (<1,000) ⚘ 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. ⚘

Packard’s Milkvetch: A Rare Idaho Native Worth Knowing About

If you’re passionate about native plants and rare botanical treasures, you’ve probably never heard of Packard’s milkvetch (Astragalus cusickii var. packardiae). And honestly, that’s not surprising – this little-known perennial is one of those plants that flies completely under the radar, even among dedicated native plant enthusiasts.

What Exactly Is Packard’s Milkvetch?

Packard’s milkvetch is a perennial plant that belongs to the legume family, making it a cousin to peas, beans, and other nitrogen-fixing plants. As a specific variety of Astragalus cusickii, it represents a unique genetic lineage that has adapted to very specific conditions in the American West.

Where Does It Call Home?

This plant is native to the lower 48 states, but don’t expect to stumble across it during your next hiking adventure. Packard’s milkvetch has an extremely limited range, currently known only from Idaho. This restricted distribution is one of the things that makes it so special – and so vulnerable.

The Rarity Factor

Here’s where things get interesting (and a bit concerning). Packard’s milkvetch appears to have a conservation status that suggests it’s quite rare, though the exact details of its conservation ranking aren’t widely documented. This rarity means that if you’re lucky enough to encounter this plant in the wild, you’re witnessing something truly special.

Should You Grow Packard’s Milkvetch?

This is where we need to pump the brakes a bit. Given its apparent rarity and extremely limited distribution, Packard’s milkvetch isn’t your typical garden center find. In fact, you’re unlikely to find it available through normal horticultural channels at all.

If you’re absolutely determined to grow this species, here are some important considerations:

  • Only source from reputable native plant specialists who can guarantee responsibly collected seed
  • Never collect from wild populations
  • Consider it more of a conservation effort than a typical gardening project
  • Be prepared for a challenging growing experience with limited guidance available

What We Don’t Know (And Why That Matters)

Unfortunately, there’s a lot we don’t know about Packard’s milkvetch. Details about its preferred growing conditions, appearance, pollinator relationships, and cultivation requirements are scarce in horticultural literature. This knowledge gap is common with rare, localized plant varieties that haven’t been extensively studied or cultivated.

Alternative Native Options

If you’re interested in growing milkvetches in your garden, consider looking into more common Astragalus species that are better documented and more readily available. Many milkvetches are excellent choices for native gardens, offering:

  • Nitrogen fixation benefits for soil health
  • Attractive flowers that appeal to native pollinators
  • Drought tolerance once established
  • Low maintenance requirements

The Bottom Line

Packard’s milkvetch represents the fascinating world of rare native plants that exist quietly in specific corners of our landscape. While it may not be practical for most home gardeners to grow, knowing about plants like this helps us appreciate the incredible diversity of native flora that surrounds us – and reminds us why habitat conservation is so important.

Instead of seeking out this rare variety, consider supporting broader milkvetch conservation by growing other native Astragalus species, protecting natural habitats, and supporting organizations that work to conserve rare plant populations. Sometimes the best way to honor a rare plant is to let it thrive in its natural home while we celebrate its more common relatives in our gardens.

Packard’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 cusickii A. Gray - Cusick'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