North America Native Plant

Washington Jacob’s-ladder

Botanical name: Polemonium pectinatum

USDA symbol: POPE14

Life cycle: perennial

Habit: forb

Native status: Native to the lower 48 states  

Washington Jacob’s-ladder: A Rare Pacific Northwest Treasure Worth Protecting If you’re a native plant enthusiast with a passion for conservation, Washington Jacob’s-ladder (Polemonium pectinatum) might just be the perfect addition to your specialized garden. This rare perennial forb represents one of the Pacific Northwest’s most precious botanical gems, though growing ...

Rare plant alert!

Region: Conservation status by state

Status: S2: 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) ⚘

Washington Jacob’s-ladder: A Rare Pacific Northwest Treasure Worth Protecting

If you’re a native plant enthusiast with a passion for conservation, Washington Jacob’s-ladder (Polemonium pectinatum) might just be the perfect addition to your specialized garden. This rare perennial forb represents one of the Pacific Northwest’s most precious botanical gems, though growing it comes with important responsibilities.

What Makes Washington Jacob’s-ladder Special

Washington Jacob’s-ladder is a native perennial that belongs to the diverse Jacob’s-ladder family. As a forb, it’s an herbaceous plant that lacks woody stems but returns year after year from its root system. Like its more common cousins, this species likely produces clusters of delicate blue to purple flowers that create a charming display in the right garden setting.

A Plant on the Edge: Understanding Its Rarity

Important Conservation Note: Washington Jacob’s-ladder carries a Global Conservation Status of S2, meaning it’s imperiled due to extreme rarity. With typically only 6 to 20 known occurrences and few remaining individuals (estimated at 1,000 to 3,000 plants), this species is especially vulnerable to extinction.

If you’re considering growing this plant, it’s crucial to source it only from reputable native plant nurseries that use responsibly collected seed or ethically propagated material. Never collect plants or seeds from wild populations.

Where It Calls Home

This remarkable plant is endemic to Washington state, making it a true regional specialty. Its limited geographic distribution contributes to its rarity status and makes it particularly vulnerable to habitat loss and environmental changes.

Should You Grow Washington Jacob’s-ladder?

This plant is ideal for:

  • Dedicated native plant gardeners interested in conservation
  • Specialized rock gardens or native plant collections
  • Gardeners in Washington state looking to support local biodiversity
  • Those participating in conservation gardening initiatives

However, it may not be the best choice if you’re looking for a readily available, easy-care garden plant. Its rarity means it’s not commonly found in nurseries, and growing it successfully requires dedication and proper sourcing.

Garden Role and Landscape Design

Washington Jacob’s-ladder works beautifully in:

  • Native plant demonstration gardens
  • Rock gardens with other Pacific Northwest natives
  • Conservation-focused landscape designs
  • Specialized collections of rare plants

Given its rarity, it’s best treated as a specimen plant rather than used for mass plantings. Consider pairing it with other Washington natives to create a regionally appropriate plant community.

Growing Conditions and Care

While specific growing requirements for Washington Jacob’s-ladder are not well-documented due to its rarity, we can make educated assumptions based on its native habitat and related species:

  • Soil: Likely prefers well-draining soil, possibly with some organic matter
  • Light: Probably thrives in partial shade to filtered sunlight
  • Water: Moderate moisture levels, avoiding both drought and waterlogging
  • Hardiness: Suitable for USDA zones typical of Washington state (likely zones 4-8)

Planting and Care Tips

Given the limited information available about this rare species, here are general guidelines:

  • Plant in spring after the last frost
  • Provide consistent but not excessive moisture during establishment
  • Mulch lightly to conserve moisture and suppress weeds
  • Monitor closely for any signs of stress or disease
  • Document your growing experience to contribute to conservation knowledge

Pollinator and Wildlife Benefits

While specific wildlife interactions aren’t well-documented for this rare species, Jacob’s-ladder plants typically attract small native bees, butterflies, and other pollinators. By growing this plant, you’re not only supporting these beneficial insects but also helping preserve genetic diversity of a threatened species.

The Bottom Line

Washington Jacob’s-ladder represents both an opportunity and a responsibility. If you can source it ethically and have the dedication to grow it properly, you’ll be participating in the conservation of a truly special plant. Just remember that with great rarity comes great responsibility – this isn’t a plant to grow casually, but rather one that deserves our most thoughtful care and attention.

Consider this plant if you’re passionate about conservation, have experience with native plants, and understand the importance of preserving our botanical heritage for future generations.

Washington Jacob’s-ladder

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

Solanales

Family

Polemoniaceae Juss. - Phlox family

Genus

Polemonium L. - Jacob's-ladder

Species

Polemonium pectinatum Greene - Washington Jacob's-ladder

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