North America Native Plant

Hall’s Milkweed

Botanical name: Asclepias hallii

USDA symbol: ASHA6

Life cycle: perennial

Habit: forb

Native status: Native to the lower 48 states  

Hall’s Milkweed: A Rare Gem for High Desert Gardens If you’re looking to add a touch of native elegance to your high desert or mountain garden, Hall’s milkweed (Asclepias hallii) might just be the perfect choice. This charming perennial milkweed brings both beauty and ecological value to landscapes across the ...

Rare plant alert!

Region: Conservation status by state

Status: S3: Status is uncertain but is somewhere between the following rankings: 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 ⚘

Hall’s Milkweed: A Rare Gem for High Desert Gardens

If you’re looking to add a touch of native elegance to your high desert or mountain garden, Hall’s milkweed (Asclepias hallii) might just be the perfect choice. This charming perennial milkweed brings both beauty and ecological value to landscapes across the American West, though its rarity makes it a special find for native plant enthusiasts.

What is Hall’s Milkweed?

Hall’s milkweed is a native perennial that calls the high desert and mountainous regions of the western United States home. As a member of the milkweed family, it shares the characteristic milky sap and pod-like seed structures that make these plants so distinctive. What sets Hall’s milkweed apart is its compact size and delicate clusters of white to pale pink flowers that bloom during the summer months.

Where Does Hall’s Milkweed Grow?

This native beauty has a relatively limited range, naturally occurring in Arizona, Colorado, Nevada, New Mexico, Utah, and Wyoming. You’ll typically find it thriving in high desert environments and mountain foothills, where it has adapted to challenging conditions including intense sun, low rainfall, and dramatic temperature swings.

A Word About Rarity

Before we dive into growing tips, there’s something important to know: Hall’s milkweed has a Global Conservation Status of S3, meaning it’s considered vulnerable. This classification indicates that the species is relatively rare throughout its range, with typically only 21 to 100 known occurrences. If you decide to grow this special plant, please ensure you source it from reputable native plant nurseries that propagate their own stock rather than wild-collecting.

Why Grow Hall’s Milkweed?

There are several compelling reasons to consider adding this rare milkweed to your garden:

  • Pollinator magnet: Like all milkweeds, it’s a crucial host plant for monarch butterflies and attracts a variety of native bees and other pollinators
  • Drought tolerance: Once established, it thrives with minimal water, making it perfect for xeriscape gardens
  • Low maintenance: This tough perennial requires little care once it’s settled in
  • Conservation value: By growing it responsibly, you’re helping preserve a vulnerable native species
  • Unique beauty: Its delicate flowers and compact form add subtle elegance to native plant gardens

Growing Conditions and Care

Hall’s milkweed is surprisingly easy to grow if you can replicate its natural habitat conditions:

Climate and Hardiness

This resilient plant thrives in USDA hardiness zones 4-8, handling both cold winters and hot, dry summers with ease.

Sun and Soil Requirements

Give your Hall’s milkweed full sun and well-draining soil. It’s particularly well-suited to sandy or rocky soils that might challenge other plants. Poor drainage is its biggest enemy, so avoid heavy clay or areas where water tends to pool.

Watering

Once established, this drought-tolerant native needs very little supplemental water. In fact, overwatering is more likely to cause problems than underwatering. During its first year, provide occasional deep watering to help establish roots, then step back and let nature take over.

Perfect Garden Settings

Hall’s milkweed shines in several garden styles:

  • Rock gardens: Its compact size and drought tolerance make it ideal for tucking between stones
  • Xeriscape designs: A natural choice for water-wise landscaping
  • Native plant gardens: Combines beautifully with other western natives
  • High-altitude landscapes: Perfect for mountain properties and high desert settings

Planting and Care Tips

Getting Hall’s milkweed established is straightforward:

  • Plant in spring after the last frost
  • Space plants about 12-18 inches apart
  • Water regularly the first year, then reduce to occasional deep watering
  • No fertilizer needed – it actually prefers lean soils
  • Allow seed pods to mature if you want to collect seeds (with permission if on private property)
  • Don’t be alarmed if it goes dormant during extreme heat – this is natural

The Bottom Line

Hall’s milkweed is a wonderful choice for gardeners in the western United States who want to support native biodiversity while creating beautiful, low-maintenance landscapes. Its rarity makes it extra special, but also means we need to be thoughtful about how we grow and share it. If you can find responsibly sourced plants or seeds, this tough little milkweed will reward you with years of delicate blooms and the satisfaction of knowing you’re helping preserve a vulnerable native species.

Just remember: with great rarity comes great responsibility. Always source your plants ethically, and consider sharing seeds with other native plant enthusiasts to help expand this special species’ garden presence while protecting its wild populations.

Hall’s Milkweed

Classification

Group

Dicot

Kingdom

Plantae - Plants

Subkingdom

Tracheobionta - Vascular plants

Superdivision

Spermatophyta - Seed plants

Division

Magnoliophyta - Flowering plants

Subdivision
Class

Magnoliopsida - Dicotyledons

Subclass

Asteridae

Order

Gentianales

Family

Asclepiadaceae Borkh. - Milkweed family

Genus

Asclepias L. - milkweed

Species

Asclepias hallii A. Gray - Hall's milkweed

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