North America Native Plant

Yadon’s Wallflower

Botanical name: Erysimum menziesii yadonii

USDA symbol: ERMEY

Life cycle: biennial

Habit: forb

Native status: Native to the lower 48 states  

Yadon’s Wallflower: A Rare California Treasure Worth Protecting If you’re passionate about California native plants, you might have heard whispers about Yadon’s wallflower (Erysimum menziesii yadonii) – one of the Golden State’s most precious botanical gems. But before you start planning where to plant this beauty in your garden, there’s ...

Rare plant alert!

Region: Conservation status by state

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

Yadon’s Wallflower: A Rare California Treasure Worth Protecting

If you’re passionate about California native plants, you might have heard whispers about Yadon’s wallflower (Erysimum menziesii yadonii) – one of the Golden State’s most precious botanical gems. But before you start planning where to plant this beauty in your garden, there’s something crucial you need to know about this extraordinary little wildflower.

What Makes Yadon’s Wallflower Special?

Yadon’s wallflower is a charming herbaceous perennial that belongs to the mustard family. As a forb – essentially a flowering plant without woody stems – it produces clusters of cheerful yellow flowers that would make any gardener’s heart skip a beat. This biennial to perennial plant stays relatively low to the ground, making it perfect for rock gardens or coastal plantings.

The bright yellow blooms are magnets for pollinators, particularly bees and butterflies, adding both beauty and ecological value to any landscape where it grows.

A Plant with a Very Exclusive Address

Here’s where things get interesting (and complicated): Yadon’s wallflower is native exclusively to California, but not just anywhere in California. This plant is incredibly picky about its real estate – it’s found only in a tiny area of the Monterey Peninsula. We’re talking about one of the most geographically restricted plants in North America!

The Rarity Reality Check

Important Notice: Yadon’s wallflower has a Global Conservation Status that indicates significant conservation concern. In fact, this subspecies is federally listed as threatened, which means it’s protected by law. This isn’t just rare – it’s critically rare, with only a handful of populations remaining in the wild.

Can You Grow Yadon’s Wallflower in Your Garden?

This is where we need to have a serious conversation. While Yadon’s wallflower would theoretically thrive in:

  • USDA hardiness zones 9-10
  • Well-draining, sandy or rocky soils
  • Full sun to partial shade conditions
  • Coastal California climates

The reality is that this plant may not be legally available for home gardeners to purchase or grow. Due to its threatened status, any cultivation should only be done with properly sourced, legally obtained plant material – and such material is extremely rare and typically reserved for conservation efforts.

Growing Conditions (If You Could Grow It)

In its natural habitat, Yadon’s wallflower thrives in:

  • Sandy, well-draining soils typical of coastal dunes
  • Areas with morning fog and mild temperatures
  • Locations with excellent air circulation
  • Drought conditions once established

The plant requires impeccable drainage – waterlogged roots are a death sentence for this species. It’s adapted to the specific microclimate of the Monterey Peninsula, with its cool, foggy summers and mild winters.

What You Can Do Instead

If you’re drawn to Yadon’s wallflower, consider these alternatives that offer similar aesthetic appeal while being more appropriate for home gardens:

  • Other Erysimum species that are more widely distributed
  • Native California wildflowers with yellow blooms
  • Locally appropriate native plants that support pollinators

The best way to honor Yadon’s wallflower is to support conservation efforts for this species and choose other native plants that won’t put additional pressure on wild populations.

A Plant That Teaches Us About Conservation

Yadon’s wallflower serves as a powerful reminder of why native plant conservation matters. This little yellow flower represents the incredible biodiversity that exists in very specific places – and how easily it can be lost.

While you might not be able to grow Yadon’s wallflower in your backyard, you can still make a difference by choosing other native plants, supporting conservation organizations, and spreading awareness about the importance of protecting our rarest plant species. Sometimes, the greatest act of gardening love is knowing when not to disturb a plant that’s already fighting for survival in the wild.

Yadon’s Wallflower

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

Erysimum L. - wallflower

Species

Erysimum menziesii (Hook.) Wettst. - Menzies' wallflower

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