North America Native Plant

Newberry’s Milkvetch

Botanical name: Astragalus newberryi var. aquarii

USDA symbol: ASNEA

Life cycle: perennial

Habit: forb

Native status: Native to the lower 48 states  

Newberry’s Milkvetch: A Rare Desert Gem Worth Knowing About Meet Newberry’s milkvetch (Astragalus newberryi var. aquarii), a fascinating perennial that represents one of nature’s more exclusive botanical offerings. While you might not find this plant at your local nursery, understanding its unique characteristics can deepen your appreciation for the incredible ...

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. ⚘

Newberry’s Milkvetch: A Rare Desert Gem Worth Knowing About

Meet Newberry’s milkvetch (Astragalus newberryi var. aquarii), a fascinating perennial that represents one of nature’s more exclusive botanical offerings. While you might not find this plant at your local nursery, understanding its unique characteristics can deepen your appreciation for the incredible diversity of native plants in the American Southwest.

Where Does Newberry’s Milkvetch Call Home?

This remarkable plant is native to the lower 48 states, with its current known distribution limited to Arizona. As a true southwestern native, it has adapted to some of the most challenging growing conditions our continent has to offer.

A Plant Shrouded in Mystery

Here’s where things get interesting – and a bit mysterious. Newberry’s milkvetch is what botanists might call an enigmatic species. Much about its specific growing habits, appearance, and ecological role remains poorly documented in standard horticultural literature. What we do know is that it’s a perennial member of the legume family, which means it likely shares some characteristics with its better-known cousins in the pea family.

The Rarity Factor: Handle With Care

Before you start planning where to plant this species in your garden, there’s something important to consider. Newberry’s milkvetch appears to have a special conservation status, suggesting it may be quite rare in the wild. This rarity is actually part of what makes it so scientifically valuable – but it also means we need to be extra thoughtful about how we interact with this species.

Should You Grow Newberry’s Milkvetch?

Given the limited information available about this variety’s specific growing requirements and its apparent rarity, most home gardeners should probably admire this plant from afar rather than attempting to cultivate it. Here’s why:

  • Limited availability of seeds or plants from reputable sources
  • Unknown specific growing requirements that could lead to cultivation failures
  • Potential conservation concerns due to its rarity status
  • Lack of documented garden performance

Better Alternatives for Desert Gardens

If you’re drawn to the idea of growing native legumes in your Arizona garden, consider these more readily available and well-documented alternatives:

  • Desert lupine (Lupinus sparsiflorus)
  • Fairy duster (Calliandra eriophylla)
  • Other more common Astragalus species native to your specific area

The Bigger Picture

While Newberry’s milkvetch might not be destined for your garden bed, it serves as a perfect reminder of why protecting native plant habitats is so crucial. Rare varieties like this one represent thousands of years of adaptation to specific environmental conditions, and they play roles in their ecosystems that we may not fully understand yet.

Sometimes the most meaningful way to appreciate a plant is simply knowing it exists and supporting the conservation of the wild spaces where it thrives. In the case of Newberry’s milkvetch, that appreciation might be the most garden-friendly approach of all.

If You Encounter This Plant in the Wild

Should you be lucky enough to spot what you think might be Newberry’s milkvetch during your desert adventures, take photos rather than samples, and consider reporting your sighting to local botanical organizations. Every observation helps scientists better understand these remarkable plants and their conservation needs.

Newberry’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 newberryi A. Gray - Newberry'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