North America Native Plant

Greene’s Rockcress

Botanical name: Arabis repanda var. greenei

USDA symbol: ARREG

Life cycle: biennial

Habit: forb

Native status: Native to the lower 48 states  

Greene’s Rockcress: A Rare California Native Worth Knowing If you’re on the hunt for unique native plants to add character to your California garden, you might have stumbled across Greene’s rockcress (Arabis repanda var. greenei). This little-known biennial deserves a closer look, though it comes with some important considerations that ...

Rare plant alert!

Region: Conservation status by state

Status: S5T2T3: Status is uncertain but is somewhere between the following rankings: Subspecies or variety is imperiled: Extremely rare due to factor(s) making it especially vulnerable to extinction. Typically 6 to 20 occurrences or few remaining individuals (1,000 to 3,000) ⚘ Subspecies or variety is 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. ⚘ 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. ⚘

Greene’s Rockcress: A Rare California Native Worth Knowing

If you’re on the hunt for unique native plants to add character to your California garden, you might have stumbled across Greene’s rockcress (Arabis repanda var. greenei). This little-known biennial deserves a closer look, though it comes with some important considerations that every responsible gardener should know.

What Makes Greene’s Rockcress Special?

Greene’s rockcress is a biennial plant, meaning it completes its life cycle over two years. In its first year, it focuses on establishing roots and foliage, then flowers and sets seed in its second year before completing its cycle. This patient approach to life makes it quite different from the instant gratification we often expect from our garden plants.

As a native species to the lower 48 states, specifically found in California, this rockcress has evolved alongside local wildlife and environmental conditions. It’s part of the mustard family (Brassicaceae), which includes familiar plants like cabbage and radishes, though this wild cousin has its own distinct personality.

The Rarity Factor: Why This Matters

Here’s where things get important for conservation-minded gardeners. Greene’s rockcress has a Global Conservation Status of S5T2T3, which indicates it has some level of rarity or conservation concern. This means that if you’re interested in growing this plant, you’ll want to be extra careful about sourcing.

Responsible growing means:

  • Only obtaining seeds or plants from reputable native plant nurseries
  • Never collecting from wild populations
  • Supporting conservation efforts through responsible cultivation

Should You Grow Greene’s Rockcress?

The honest truth is that information about this specific variety is quite limited in standard gardening resources. This scarcity of cultivation information, combined with its rarity status, suggests that Greene’s rockcress might be better appreciated in its natural habitat rather than in home gardens.

For most gardeners looking to support native California plants, there are many other well-documented native alternatives that would be easier to grow successfully and more readily available from ethical sources.

Better Native Alternatives

If you’re drawn to the idea of growing California native rockcress species, consider these more commonly available alternatives:

  • Other Arabis species that are less rare and better documented
  • Native wildflowers that provide similar ecological benefits
  • Well-established California native plants from local nurseries

Supporting Conservation

Sometimes the best way to support a rare native plant is to appreciate it in its natural setting and support habitat conservation efforts. Consider:

  • Volunteering with local native plant societies
  • Supporting habitat preservation organizations
  • Learning about and growing more common native species that support the same ecosystems

The Bottom Line

While Greene’s rockcress is undoubtedly a fascinating native plant, its rarity and the limited information available about its cultivation make it a challenging choice for most home gardeners. The most responsible approach is to admire this species in its natural habitat while choosing better-documented native alternatives for your garden projects.

Remember, creating wildlife-friendly native gardens is about supporting entire ecosystems, not necessarily growing the rarest plants. Sometimes the most common natives are the real workhorses that make the biggest difference for local wildlife and pollinators.

Greene’s Rockcress

Classification

Group

Dicot

Kingdom

Plantae - Plants

Subkingdom

Tracheobionta - Vascular plants

Superdivision

Spermatophyta - Seed plants

Division

Magnoliophyta - Flowering plants

Subdivision
Class

Magnoliopsida - Dicotyledons

Subclass

Dilleniidae

Order

Capparales

Family

Brassicaceae Burnett - Mustard family

Genus

Arabis L. - rockcress

Species

Arabis repanda S. Watson - Yosemite rockcress

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