North America Native Plant

Basalt Larkspur

Botanical name: Delphinium basalticum

USDA symbol: DEBA9

Life cycle: perennial

Habit: forb

Native status: Native to the lower 48 states  

Basalt Larkspur: A Rare Pacific Northwest Native Worth Protecting Meet the basalt larkspur (Delphinium basalticum), a stunning yet uncommon native wildflower that calls the volcanic soils of the Pacific Northwest home. This perennial beauty is more than just another pretty face in the garden – it’s a rare treasure that ...

Rare plant alert!

Region: Conservation status by state

Status: S2S3: Status is uncertain but is somewhere between the following rankings: Imperiled: Extremely rare due to factor(s) making it especially vulnerable to extinction. Typically 6 to 20 occurrences or few remaining individuals (1,000 to 3,000) ⚘ 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 ⚘

Basalt Larkspur: A Rare Pacific Northwest Native Worth Protecting

Meet the basalt larkspur (Delphinium basalticum), a stunning yet uncommon native wildflower that calls the volcanic soils of the Pacific Northwest home. This perennial beauty is more than just another pretty face in the garden – it’s a rare treasure that deserves our attention and respect.

What Makes Basalt Larkspur Special

The basalt larkspur is a true Pacific Northwest native, found naturally only in Oregon and Washington. As its name suggests, this delphinium has a particular affinity for basalt-derived soils – those rich, volcanic soils that make the region so unique. It’s a herbaceous perennial that produces the classic delphinium flower spikes we all love, with beautiful blue to purple blooms that tower above the landscape.

This isn’t your typical garden-variety delphinium, though. Basalt larkspur is considered rare, with a Global Conservation Status of S2S3, meaning its populations are quite limited in the wild.

A Pollinator’s Paradise

Like other delphiniums, basalt larkspur is a pollinator magnet. Those distinctive spurred flowers are perfectly designed for long-tongued visitors like hummingbirds and specialized native bees. The tubular shape and rich nectar rewards make it an important food source for these creatures, especially in its native range where such specialized relationships have evolved over thousands of years.

Growing Basalt Larkspur: Handle with Care

Here’s where things get important: if you’re interested in growing this beauty, you absolutely must source it responsibly. Never collect plants or seeds from wild populations – this rare species needs every individual it can get in its natural habitat.

Ideal Growing Conditions

Basalt larkspur thrives in USDA hardiness zones 7-9, which perfectly matches its Pacific Northwest origins. Here’s what this special plant needs to flourish:

  • Soil: Well-draining soil, ideally with some basaltic content, though it can adapt to other well-draining soils
  • Light: Partial shade to full sun, though some afternoon shade is appreciated in hotter climates
  • Water: Moderate moisture – not too wet, not too dry
  • Space: Room to grow tall and show off those spectacular flower spikes

Perfect Garden Companions

In a native plant garden or naturalistic landscape, basalt larkspur serves as an excellent vertical accent. Its tall flower spikes create dramatic height and structure, making it perfect for the back of borders or as a statement piece in wildflower meadows. Pair it with other Pacific Northwest natives like Oregon grape, salal, or native sedges for an authentic regional look.

Planting and Care Tips

Once you’ve sourced your basalt larkspur from a reputable native plant nursery, here’s how to give it the best start:

  • Plant in fall for best establishment
  • Ensure excellent drainage – soggy soils are this plant’s enemy
  • Mulch lightly to retain moisture and suppress weeds
  • Provide some wind protection if your garden is exposed
  • Allow the plant to go dormant naturally in winter

Why Choose Basalt Larkspur

By choosing to grow basalt larkspur, you’re not just adding a beautiful plant to your garden – you’re becoming a conservation partner. This rare native brings authentic regional character to your landscape while supporting local pollinators and preserving genetic diversity of this special species.

Just remember: with great beauty comes great responsibility. Always source this plant ethically, and consider yourself a steward of this remarkable Pacific Northwest treasure.

Basalt Larkspur

Classification

Group

Dicot

Kingdom

Plantae - Plants

Subkingdom

Tracheobionta - Vascular plants

Superdivision

Spermatophyta - Seed plants

Division

Magnoliophyta - Flowering plants

Subdivision
Class

Magnoliopsida - Dicotyledons

Subclass

Magnoliidae

Order

Ranunculales

Family

Ranunculaceae Juss. - Buttercup family

Genus

Delphinium L. - larkspur

Species

Delphinium basalticum Warnock - basalt larkspur

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