North America Native Plant

Pinaleno Mountain Rubberweed

Botanical name: Hymenoxys ambigens

USDA symbol: HYAM8

Life cycle: perennial

Habit: forb

Native status: Native to the lower 48 states  

Pinaleno Mountain Rubberweed: A Hidden Gem for Native Plant Enthusiasts If you’re on the hunt for a truly unique native wildflower that most gardeners have never heard of, let me introduce you to Pinaleno Mountain rubberweed (Hymenoxys ambigens). This charming little perennial might not win any popularity contests, but it’s ...

Rare plant alert!

Region: Conservation status by state

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

Pinaleno Mountain Rubberweed: A Hidden Gem for Native Plant Enthusiasts

If you’re on the hunt for a truly unique native wildflower that most gardeners have never heard of, let me introduce you to Pinaleno Mountain rubberweed (Hymenoxys ambigens). This charming little perennial might not win any popularity contests, but it’s got some serious appeal for those who appreciate rare native plants and want to support local ecosystems.

What Makes This Plant Special

Pinaleno Mountain rubberweed is a native forb—basically a non-woody perennial herb—that calls the mountainous regions of the American Southwest home. As a member of the sunflower family, it produces cheerful yellow daisy-like blooms that bring a splash of sunshine to any native garden during the summer months.

What really sets this plant apart is its rarity. With a conservation status that’s still being defined, this is one of those plants that deserves more attention from native plant enthusiasts who want to make a real difference in preserving regional biodiversity.

Where It Naturally Grows

This little beauty is found exclusively in Arizona and New Mexico, where it thrives in the unique conditions of the southwestern mountains. It’s perfectly adapted to the climate and soils of this region, making it an authentic choice for gardeners in these areas.

Why You Might Want to Grow It

Here are some compelling reasons to consider adding Pinaleno Mountain rubberweed to your garden:

  • It’s a true native that supports local ecosystems
  • Low maintenance once established—perfect for busy gardeners
  • Drought tolerant, making it ideal for water-wise landscaping
  • Attracts native pollinators like bees and butterflies
  • Adds authentic regional character to native plant gardens
  • Helps preserve a rare species through cultivation

Perfect Garden Settings

This plant shines in:

  • Native wildflower gardens
  • Xeriscape and drought-tolerant landscapes
  • Mountain or high desert themed gardens
  • Naturalized areas where you want a wild look

Growing Conditions and Care

Pinaleno Mountain rubberweed is refreshingly easy to please once you understand its preferences:

Sunlight: Full sun is best—this plant loves basking in bright light just like it does in its native mountain habitats.

Soil: Well-draining soil is absolutely essential. It can’t tolerate soggy conditions, so avoid heavy clay or areas where water pools.

Water: Once established, it’s quite drought tolerant. Water regularly the first year to help it get established, then back off and let nature take over.

Climate: Hardy in USDA zones 5-8, which covers most areas where it naturally occurs.

A Word About Responsible Sourcing

Here’s something important to keep in mind: because this plant has an uncertain conservation status, it’s crucial to source it responsibly. Never dig plants from the wild! Instead, look for nurseries that specialize in native plants and can provide ethically propagated specimens. You might need to do some hunting to find it, but that just makes it more special when you do.

Planting and Care Tips

Getting started with Pinaleno Mountain rubberweed is straightforward:

  • Plant in spring after the last frost
  • Choose a sunny spot with excellent drainage
  • Water regularly the first growing season to establish roots
  • After establishment, water only during extended dry periods
  • No fertilizer needed—it’s adapted to lean soils
  • Deadhead spent flowers to encourage more blooms

The Bottom Line

Pinaleno Mountain rubberweed might not be the flashiest plant in the garden center, but it’s got something special that many common garden plants lack: authenticity and ecological value. For gardeners in Arizona and New Mexico who want to create landscapes that truly reflect their region’s natural heritage while supporting rare native species, this little wildflower is worth seeking out.

Just remember to source it responsibly, be patient with establishment, and enjoy watching the native pollinators discover this hidden gem in your garden!

Pinaleno Mountain Rubberweed

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

Asterales

Family

Asteraceae Bercht. & J. Presl - Aster family

Genus

Hymenoxys Cass. - rubberweed

Species

Hymenoxys ambigens (S.F. Blake) Bierner - Pinaleno Mountain rubberweed

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