Native Plants

Carson Valley Monkeyflower

Erythranthe carsonensis

USDA symbol: ERCA9

annual forb

Lower 48 states: native

Meet the Carson Valley monkeyflower (Erythranthe carsonensis), also known as the bonanza monkeyflower – a tiny native wildflower that packs a big conservation punch. This delicate annual is one of those special plants that makes you appreciate the incredible diversity hiding in our native landscapes, even if most gardeners have ...

Carson Valley Monkeyflower may be listed as rare in your area.
Global Conservation Status

Status: S1 | Critically imperiled: Typically 5 or fewer occurrences or under 1,000 remaining individuals.

Carson Valley Monkeyflower: A Rare Native Gem Worth Protecting

Meet the Carson Valley monkeyflower (Erythranthe carsonensis), also known as the bonanza monkeyflower – a tiny native wildflower that packs a big conservation punch. This delicate annual is one of those special plants that makes you appreciate the incredible diversity hiding in our native landscapes, even if most gardeners have never heard of it.

A Critically Rare Native Treasure

Before we dive into growing this beauty, there’s something crucial you need to know: the Carson Valley monkeyflower is critically imperiled. With a Global Conservation Status of S1, this means there are typically only 5 or fewer known populations, with very few remaining individuals (fewer than 1,000 total). That makes this little wildflower rarer than many animals on the endangered species list!

This annual forb is native to the lower 48 states, specifically calling California and Nevada home. True to its name, it’s particularly associated with the Carson Valley region, where it clings to existence in a landscape that has seen dramatic changes over the past century.

  • Species observed
  • No observations

What Makes This Monkeyflower Special

As a member of the monkeyflower family (formerly classified under Mimulus rubellus var. latiflorus), the Carson Valley monkeyflower produces the characteristic snapdragon-like blooms that give monkeyflowers their whimsical name. These small, typically yellow flowers may seem modest, but they represent millions of years of evolution perfectly adapted to their specific mountain and valley habitats.

Being an annual forb means this plant completes its entire life cycle in a single growing season, producing seeds that must survive harsh winters to continue the species. It lacks woody tissue, instead channeling all its energy into rapid growth, flowering, and seed production during favorable conditions.

Should You Grow Carson Valley Monkeyflower?

Here’s where things get complicated. While this native plant would theoretically make a wonderful addition to native gardens, rock gardens, or specialized conservation collections, its critically imperiled status means we need to be extremely cautious.

If you’re considering growing this species, please only do so with responsibly sourced material from reputable native plant organizations or conservation programs. Never collect seeds or plants from wild populations – those few remaining individuals are far too precious to disturb.

Potential Growing Conditions

While specific cultivation information for Carson Valley monkeyflower is limited due to its rarity, we can make educated guesses based on its native habitat and related species:

  • Climate: Likely suited for USDA hardiness zones 6-9, matching its California and Nevada range
  • Soil: Probably prefers well-draining soils typical of mountain and valley environments
  • Water: As an annual, likely needs moderate moisture during growing season
  • Sun: Most monkeyflowers prefer partial sun to light shade
  • Garden type: Best suited for native plant gardens, rock gardens, or conservation collections

Conservation Over Cultivation

Rather than focusing solely on growing this rare beauty, consider how you can support its conservation. You might:

  • Support native plant conservation organizations working in California and Nevada
  • Plant other native monkeyflower species that are more common and equally beautiful
  • Create habitat for native pollinators that might also benefit rare species like this one
  • Spread awareness about the importance of protecting native plant populations

The Bigger Picture

The Carson Valley monkeyflower reminds us that our native flora includes countless species most people never see – and some that are hanging on by the thinnest of threads. While we may not all be able to grow this particular gem in our gardens, we can all play a role in protecting the wild places where such rarities still survive.

Sometimes the best way to love a plant is to leave it wild and focus our gardening efforts on supporting the broader ecosystem it calls home. In the case of the Carson Valley monkeyflower, that might just be the most gardener-like thing we can do.

Erythranthe carsonensis is also known as...

Often we refer to plants by their common names. When shopping for plants the scientific name is the best way to positively identify the plant species you desire. But some plants have more than one name! While it doesn't happen often, nurseries might display one name while you're searching for another. Erythranthe carsonensis is also known as:

Mimulus rubellus Gray var. latiflorus | USDA symbol: MIRUL

Why do some plants have more than one name? Over time plant species may be renamed for a few reasons:

  1. Botanists in different regions named the same plant without knowing it had already been classified.
  2. A species was reclassified after scientific advances in, for example, DNA analysis.
  3. Slight variations within a species are sometimes mistakenly identified as entirely new species.

Classification

Group: Dicot
Kingdom: Plantae - Plants
Subkingdom: Tracheobionta - Vascular plants
Superdivision: Spermatophyta - Seed plants
Division: Magnoliophyta - Flowering plants
Class: Magnoliopsida - Dicotyledons
Subclass: Asteridae
Order: Scrophulariales
Family: Scrophulariaceae Juss. - Figwort family
Genus: Erythranthe Spach - monkeyflower

Species: Erythranthe carsonensis N.S. Fraga - Carson Valley monkeyflower

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