North America Native Plant

Smoothflower Lousewort

Botanical name: Pedicularis bracteosa var. siifolia

USDA symbol: PEBRS

Life cycle: perennial

Habit: forb

Native status: Native to the lower 48 states  

Synonyms: Pedicularis siifolia Rydb. (PESI5)   

Smoothflower Lousewort: A Hidden Gem for Native Plant Enthusiasts If you’re looking to add a touch of wild mountain beauty to your garden, smoothflower lousewort (Pedicularis bracteosa var. siifolia) might just be the perfect conversation starter you never knew you needed. Despite its rather unfortunate common name – which has ...

Rare plant alert!

Region: Conservation status by state

Status: S5T1T3: Status is uncertain but is somewhere between the following rankings: Subspecies or variety is critically Imperiled: Extremely rare due to factor(s) making it especially vulnerable to extinction. Typically 5 or fewer occurrences or very few remaining individuals (<1,000) ⚘ Subspecies or variety is 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. ⚘ Secure: At very low or no risk of extinction in the jurisdiction due to a very extensive range, abundant populations or occurrences, with little to no concern from declines or threats. ⚘

Smoothflower Lousewort: A Hidden Gem for Native Plant Enthusiasts

If you’re looking to add a touch of wild mountain beauty to your garden, smoothflower lousewort (Pedicularis bracteosa var. siifolia) might just be the perfect conversation starter you never knew you needed. Despite its rather unfortunate common name – which has nothing to do with actual lice – this native perennial brings elegant purple blooms and delicate foliage to gardens across the Pacific Northwest.

What Makes Smoothflower Lousewort Special?

This charming native forb is a true Northwestern treasure, naturally occurring in Idaho, Montana, and Washington. As a perennial plant, it returns year after year, developing into a reliable garden performer once established. The plant produces stunning purple-pink flowers arranged in dense, showy spikes that rise above deeply divided, fern-like foliage.

Smoothflower lousewort grows naturally across the mountainous regions of the Pacific Northwest, thriving in the diverse ecosystems of three western states.

Garden Design Potential

This native beauty shines brightest in:

  • Native plant gardens where authenticity matters
  • Wildflower meadows seeking natural charm
  • Mountain-style landscapes
  • Naturalized areas that mimic wild habitats

The plant’s unique flower structure and attractive foliage make it an excellent accent plant, drawing the eye without overwhelming nearby companions. Its moderate size makes it perfect for middle-ground plantings in perennial borders.

Pollinator Paradise

One of the best reasons to grow smoothflower lousewort is its value to native pollinators. The specialized flower structure attracts bees and other beneficial insects, making it a wonderful addition to any pollinator-friendly garden. By choosing native plants like this one, you’re supporting local ecosystems and helping maintain biodiversity.

Growing Conditions and Care

Smoothflower lousewort thrives in USDA hardiness zones 3-7, making it suitable for most northern and mountainous regions. Here’s what this mountain native needs to flourish:

  • Sunlight: Partial shade to full sun
  • Soil: Moist, well-draining soil enriched with organic matter
  • Water: Consistent moisture without waterlogging
  • pH: Adaptable to various soil pH levels

Planting and Care Tips

Success with smoothflower lousewort starts with understanding its mountain origins. These plants appreciate:

  • Regular watering during dry spells, especially in summer
  • Mulching to retain soil moisture and suppress weeds
  • Adding compost or leaf mold to improve soil structure
  • Avoiding overly rich, fertilized soils that can cause weak growth

Once established, this perennial requires minimal maintenance, making it an excellent choice for low-maintenance native gardens.

A Note About Conservation

Smoothflower lousewort has a conservation status that suggests it may be uncommon in parts of its range. If you decide to add this beauty to your garden, please source plants or seeds from reputable native plant nurseries that practice responsible collection and propagation. Never collect plants from wild populations, as this can harm already vulnerable native plant communities.

The Bottom Line

Despite its quirky name, smoothflower lousewort deserves a place in native plant gardens across the Pacific Northwest. It offers beautiful flowers, attracts beneficial pollinators, and connects your garden to the region’s natural heritage. With proper growing conditions and responsible sourcing, this native perennial can become a treasured part of your landscape for years to come.

Whether you’re creating a native plant showcase or simply want to support local wildlife, smoothflower lousewort proves that sometimes the most rewarding garden plants are the ones that have been thriving in your region all along.

Smoothflower Lousewort

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

Pedicularis L. - lousewort

Species

Pedicularis bracteosa Benth. - bracted lousewort

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