North America Native Plant

Shieldplant

Botanical name: Streptanthus tortuosus var. orbiculatus

USDA symbol: STTOO

Life cycle: biennial

Habit: subshrub

Native status: Native to the lower 48 states  

Shieldplant: A Native Wildflower Worth Discovering If you’re on the hunt for lesser-known native plants to add some authentic regional character to your garden, let me introduce you to shieldplant (Streptanthus tortuosus var. orbiculatus). This charming member of the mustard family might not be a household name, but it’s a ...

Shieldplant: A Native Wildflower Worth Discovering

If you’re on the hunt for lesser-known native plants to add some authentic regional character to your garden, let me introduce you to shieldplant (Streptanthus tortuosus var. orbiculatus). This charming member of the mustard family might not be a household name, but it’s a genuine native wildflower that deserves a spot on your radar.

What Is Shieldplant?

Shieldplant is a native forb that grows naturally across parts of the American West. As a non-woody herbaceous plant, it maintains a humble profile in the landscape while offering the authentic character that only true natives can provide. This plant can exhibit annual, biennial, or perennial growth patterns depending on growing conditions, making it an adaptable choice for patient gardeners.

Where Does Shieldplant Grow Naturally?

This native beauty calls California, Nevada, and Oregon home, thriving in the diverse landscapes of the western United States. Its natural range suggests it’s well-adapted to the climate patterns and growing conditions typical of these regions.

Why Consider Shieldplant for Your Garden?

Here’s where I need to be upfront with you: shieldplant is one of those wonderful natives that hasn’t made it into mainstream horticulture yet. While this means specific cultivation information is limited, it also means you’d be growing something truly special and uncommon in home landscapes.

As a member of the mustard family, shieldplant likely offers several benefits:

  • Attracts pollinators with its small flowers
  • Provides authentic regional character
  • Supports local ecosystem relationships
  • Requires minimal intervention once established

Growing Conditions and Care

While specific cultivation details for this variety are scarce, we can make educated guesses based on its native habitat and family characteristics. Shieldplant likely prefers:

  • Well-draining soils
  • Full sun to partial shade
  • Minimal supplemental watering once established
  • USDA hardiness zones 7-10 (based on its geographic range)

The Reality Check

Here’s the thing about shieldplant: it’s not readily available at your local garden center, and detailed growing guides are few and far between. This makes it more of an adventure plant for dedicated native plant enthusiasts rather than a beginner-friendly choice.

If you’re determined to grow shieldplant, your best bet is connecting with native plant societies in California, Nevada, or Oregon, or seeking out specialty native plant nurseries that might carry seeds or plants.

Is Shieldplant Right for Your Garden?

Consider shieldplant if you:

  • Live within its natural range
  • Love experimenting with uncommon natives
  • Have experience with wildflower gardening
  • Want to support local pollinators with authentic regional plants

Skip it if you:

  • Prefer plants with established cultivation requirements
  • Want immediate gratification from readily available plants
  • Are new to native plant gardening

While shieldplant remains something of a mystery in cultivation, it represents the exciting frontier of native plant gardening—where dedicated enthusiasts work to bring authentic regional plants back into our landscapes, one garden at a time.

Shieldplant

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

Streptanthus Nutt. - twistflower

Species

Streptanthus tortuosus Kellogg - shieldplant

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