North America Native Plant

Macbride Cleomella

Botanical name: Cleomella macbrideana

USDA symbol: CLMA3

Life cycle: annual

Habit: forb

Native status: Native to the lower 48 states  

MacBride Cleomella: Idaho’s Mysterious Native Annual If you’re looking for a truly unique addition to your native plant garden, MacBride cleomella (Cleomella macbrideana) might just be the conversation starter you never knew you needed. This little-known native annual is one of Idaho’s botanical secrets—so secret, in fact, that finding detailed ...

MacBride Cleomella: Idaho’s Mysterious Native Annual

If you’re looking for a truly unique addition to your native plant garden, MacBride cleomella (Cleomella macbrideana) might just be the conversation starter you never knew you needed. This little-known native annual is one of Idaho’s botanical secrets—so secret, in fact, that finding detailed information about it feels like a treasure hunt!

What Exactly Is MacBride Cleomella?

MacBride cleomella is a native annual forb that belongs to the spider flower family. As a forb, it’s an herbaceous flowering plant without woody stems—think of it as nature’s version of a seasonal wildflower that completes its entire life cycle in just one growing season. This plant is exclusively native to Idaho, making it a true regional specialty.

Where Does It Call Home?

This plant has chosen Idaho as its one and only home state within the lower 48 states. Its extremely limited distribution makes it something of a botanical unicorn—you won’t find MacBride cleomella growing wild anywhere else in the country.

Should You Grow MacBride Cleomella?

Here’s where things get interesting (and a bit challenging). While MacBride cleomella has the appeal of being a true Idaho native, the reality is that very little is known about its cultivation requirements, appearance, or garden performance. This mystery plant falls into the category of proceed with curiosity and caution.

The Pros of Planting MacBride Cleomella:

  • It’s a genuine Idaho native, supporting local ecosystems
  • Annual plants often provide quick results and seasonal interest
  • You’d have serious bragging rights as possibly the only gardener in your neighborhood growing this species
  • Contributing to the cultivation of rare native plants helps preserve biodiversity

The Challenges:

  • Seeds or plants are likely extremely difficult (if not impossible) to source commercially
  • Growing requirements are largely unknown
  • No information available about its ornamental value or garden performance
  • Its rarity might indicate very specific habitat needs that are hard to replicate

Growing Conditions and Care

Unfortunately, specific growing requirements for MacBride cleomella remain a mystery. As an annual forb native to Idaho, it likely adapted to the state’s varied climatic conditions, but without more research, it’s impossible to provide concrete cultivation advice.

If you’re determined to try growing this plant, your best bet would be to:

  • Contact Idaho native plant societies or botanical gardens for guidance
  • Research the specific habitat where it’s been found growing wild
  • Start with general conditions suitable for Idaho native annuals
  • Ensure any seeds or plants are ethically and legally sourced

Alternative Native Options

If MacBride cleomella proves too elusive for your garden, consider other members of the Cleomella genus or related spider flowers that are easier to source and grow. These alternatives can give you a similar botanical experience while supporting native plant cultivation.

The Bottom Line

MacBride cleomella represents one of gardening’s ultimate challenges—growing a plant that’s so uncommon, it’s practically mythical. While it might not be the practical choice for most gardeners, it certainly embodies the spirit of native plant conservation. If you’re an experienced native plant enthusiast with connections to Idaho’s botanical community, this could be an exciting project. For most gardeners, though, starting with better-known Idaho natives might be a more rewarding path to supporting local ecosystems.

Sometimes the most fascinating plants are the ones that remain just out of reach, reminding us that there’s still so much to discover in the world of native flora.

Macbride Cleomella

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

Capparaceae Juss. - Caper family

Genus

Cleomella DC. - stinkweed

Species

Cleomella macbrideana Payson - MacBride cleomella

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