North America Native Plant

Ahart’s Cluster Rose

Botanical name: Rosa pisocarpa ahartii

USDA symbol: ROPIA

Life cycle: perennial

Habit: subshrub

Native status: Native to the lower 48 states  

Ahart’s Cluster Rose: A Mysterious Native Rose Worth Investigating If you’ve stumbled across the name Ahart’s cluster rose in your native plant research, you’ve discovered something of a botanical mystery. This intriguing rose goes by the scientific name Rosa pisocarpa ahartii, but finding detailed information about this specific variety can ...

Ahart’s Cluster Rose: A Mysterious Native Rose Worth Investigating

If you’ve stumbled across the name Ahart’s cluster rose in your native plant research, you’ve discovered something of a botanical mystery. This intriguing rose goes by the scientific name Rosa pisocarpa ahartii, but finding detailed information about this specific variety can be quite the treasure hunt!

What We Know About This Native Rose

Ahart’s cluster rose is classified as a perennial shrub native to the lower 48 states. Like other members of the rose family, it’s a multi-stemmed woody plant that typically stays under 13-16 feet in height, though most shrub roses remain much more compact in garden settings.

Where Does It Grow?

This native rose calls California and Oregon home, fitting right into the Pacific Coast’s diverse plant communities. Being native to this region means it has evolved alongside local wildlife and climate patterns over thousands of years.

The Challenge: Limited Information Available

Here’s where things get interesting (and a bit frustrating for us plant nerds): detailed information about Rosa pisocarpa ahartii specifically is surprisingly scarce in mainstream botanical databases and native plant resources. This could mean a few things:

  • It might be an extremely rare or localized variety
  • The taxonomic classification could be outdated or disputed
  • It may be a regional name not widely recognized in botanical circles

Should You Plant It?

Given the uncertainty surrounding this specific rose, here’s my advice: if you’re interested in native roses for your California or Oregon garden, consider starting with the well-documented parent species, Rosa pisocarpa (cluster rose). This gorgeous native offers:

  • Beautiful pink flowers that attract pollinators
  • Colorful rose hips that feed birds
  • Natural adaptation to local growing conditions
  • Low maintenance once established

The Bottom Line

While Ahart’s cluster rose remains something of an enigma, don’t let that discourage your native plant journey! California and Oregon are home to several wonderful native rose species that are readily available and well-suited to sustainable landscaping. If you’re specifically interested in Rosa pisocarpa ahartii, I’d recommend reaching out to local botanical gardens, native plant societies, or university extension offices in your area—they might have the local knowledge that online databases lack.

Sometimes the most rewarding garden adventures start with a little mystery, and who knows? You might just help solve this botanical puzzle along the way!

Ahart’s Cluster Rose

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

Rosales

Family

Rosaceae Juss. - Rose family

Genus

Rosa L. - rose

Species

Rosa pisocarpa A. Gray - cluster rose

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