North America Native Plant

Dimorphic Snapdragon

Botanical name: Sairocarpus subcordatus

USDA symbol: SASU8

Life cycle: annual

Habit: forb

Native status: Native to the lower 48 states  

Synonyms: Antirrhinum subcordatum A. Gray (ANSU4)   

Dimorphic Snapdragon: A Rare California Native Worth Growing Responsibly If you’re passionate about California native plants and love the charm of snapdragons, you might want to get acquainted with the dimorphic snapdragon (Sairocarpus subcordatus). This delightful little wildflower brings all the appeal of its garden cousins while supporting local ecosystems—but ...

Rare plant alert!

Region: Conservation status by state

Status: S3: Status is uncertain but is somewhere between the following rankings: 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 ⚘

Dimorphic Snapdragon: A Rare California Native Worth Growing Responsibly

If you’re passionate about California native plants and love the charm of snapdragons, you might want to get acquainted with the dimorphic snapdragon (Sairocarpus subcordatus). This delightful little wildflower brings all the appeal of its garden cousins while supporting local ecosystems—but there’s an important catch that responsible gardeners need to know about.

What Is Dimorphic Snapdragon?

The dimorphic snapdragon is an annual forb that belongs to the snapdragon family. As a forb, it’s essentially a soft-stemmed flowering plant without woody tissue—think of it as nature’s version of a garden annual, but one that’s been perfectly adapted to California’s unique climate over thousands of years.

You might also see this plant listed under its former botanical name, Antirrhinum subcordatum, in older gardening resources or plant databases.

Where Does It Grow Naturally?

This charming native is found exclusively in California, making it a true Golden State endemic. Its natural range is quite limited within the state, which brings us to an important point about conservation.

A Important Conservation Note

Here’s where things get serious for a moment: the dimorphic snapdragon has a Global Conservation Status of S3, meaning it’s considered vulnerable. With typically only 21 to 100 known occurrences and between 3,000 to 10,000 individuals in the wild, this little beauty is genuinely rare.

What does this mean for gardeners? If you want to grow this plant, you absolutely must source it responsibly. Never collect seeds or plants from wild populations—this could harm already vulnerable communities. Instead, look for reputable native plant nurseries that propagate their stock ethically, or participate in conservation seed collection programs.

Why Grow Dimorphic Snapdragon?

Despite its rarity concerns, there are compelling reasons to include this plant in your California native garden:

  • It supports local pollinators, particularly small native bees and beneficial insects
  • As an annual, it adds seasonal interest and can fill gaps between perennial plantings
  • It’s drought-tolerant once established, perfect for water-wise landscaping
  • The small snapdragon-like flowers add delicate beauty to wildflower gardens
  • Growing it helps preserve genetic diversity of this vulnerable species

Garden Design Ideas

The dimorphic snapdragon works beautifully in several garden styles:

  • Native wildflower meadows: Let it naturalize among other California annuals
  • Rock gardens: Its compact size makes it perfect for tucking into crevices
  • Drought-tolerant landscapes: Pair with other water-wise California natives
  • Container gardens: Grow it in pots to better control its environment

Growing Conditions and Care

Like many California natives, the dimorphic snapdragon prefers conditions that mimic its natural habitat:

  • Sunlight: Full sun to partial shade
  • Soil: Well-draining soils; avoid heavy clay or constantly moist conditions
  • Water: Drought-tolerant once established, but appreciates some water during germination and early growth
  • Climate zones: USDA zones 8-10 (matches California’s Mediterranean climate)

Planting and Care Tips

Growing dimorphic snapdragon successfully requires understanding its annual lifecycle:

  • Timing: Direct sow seeds in fall or early spring to align with natural rainfall patterns
  • Soil prep: Ensure excellent drainage—this plant doesn’t tolerate wet feet
  • Watering: Provide regular moisture during germination, then gradually reduce as plants establish
  • Maintenance: Allow plants to set seed if you want them to return next year
  • Spacing: Give plants room to grow and good air circulation

The Bottom Line

The dimorphic snapdragon is a wonderful addition to California native gardens, but it comes with a responsibility. If you choose to grow this rare beauty, make sure you’re doing so ethically and helping contribute to its conservation rather than its decline. When sourced and grown responsibly, it’s a delightful way to connect your garden to California’s unique botanical heritage while supporting local wildlife.

Remember: native doesn’t always mean common. Sometimes the most special plants in our gardens are the ones that need our protection the most.

Dimorphic Snapdragon

Classification

Group

Dicot

Kingdom

Plantae - Plants

Subkingdom

Tracheobionta - Vascular plants

Superdivision

Spermatophyta - Seed plants

Division

Magnoliophyta - Flowering plants

Subdivision
Class

Magnoliopsida - Dicotyledons

Subclass

Asteridae

Order

Scrophulariales

Family

Scrophulariaceae Juss. - Figwort family

Genus

Sairocarpus D.A. Sutton - snapdragon

Species

Sairocarpus subcordatus (A. Gray) D.A. Sutton - dimorphic snapdragon

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