North America Native Plant

Smooth Prickly Phlox

Botanical name: Linanthus glabrum

USDA symbol: LIGL6

Life cycle: perennial

Habit: subshrub

Native status: Native to the lower 48 states  

Synonyms: Leptodactylon glabrum R. Patt. & Yoder-Will. (LEGL6)   

Smooth Prickly Phlox: A Rare Gem for the Native Plant Enthusiast If you’re drawn to unique native plants that tell a story of resilience and rarity, smooth prickly phlox might just capture your gardening heart. This diminutive perennial, scientifically known as Linanthus glabrum, is one of those special plants that ...

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) ⚘

Smooth Prickly Phlox: A Rare Gem for the Native Plant Enthusiast

If you’re drawn to unique native plants that tell a story of resilience and rarity, smooth prickly phlox might just capture your gardening heart. This diminutive perennial, scientifically known as Linanthus glabrum, is one of those special plants that makes you feel like you’re part of something important – conservation in your own backyard.

What Makes Smooth Prickly Phlox Special

Don’t let the prickly in its name scare you away – this little charmer is actually quite well-behaved. Smooth prickly phlox is a forb herb, meaning it’s a non-woody perennial that dies back to ground level each winter but returns faithfully each spring. What sets it apart is its incredibly rare status and its ability to thrive in some of the harshest conditions the American West has to offer.

Where You’ll Find This Native Treasure

Smooth prickly phlox calls the Great Basin home, naturally occurring in just two states: Idaho and Nevada. This limited geographic distribution is part of what makes this plant so special – and so vulnerable.

Important Conservation Note: Linanthus glabrum has a Global Conservation Status of S2, which means it’s considered Imperiled. With only 6 to 20 known occurrences and an estimated 1,000 to 3,000 individual plants remaining in the wild, this species is extremely rare and vulnerable to extinction.

Should You Grow Smooth Prickly Phlox?

Here’s where things get interesting – and where your gardening choices can make a real difference. While smooth prickly phlox would make a fascinating addition to the right garden, its rarity means you should only consider planting it if you can source it responsibly.

If you choose to grow it, here’s why it might work for you:

  • You’re passionate about native plant conservation
  • You have experience with alpine or desert plants
  • You can provide the specific growing conditions it needs
  • You can source seeds or plants from reputable native plant societies or conservation programs

You might want to skip it if:

  • You prefer low-maintenance, easy-care plants
  • Your garden has heavy, clay soil or stays moist
  • You’re looking for a showy, attention-grabbing plant
  • You can’t find responsibly sourced material

Growing Conditions and Care

Smooth prickly phlox isn’t your typical garden center find, and that’s partly because it has very specific needs that mirror its harsh native habitat.

What it needs to thrive:

  • Drainage, drainage, drainage: This cannot be overstated. Think desert-level drainage
  • Full sun: At least 6-8 hours of direct sunlight daily
  • Poor to moderate soil: Rich, fertile soil will actually harm this plant
  • Minimal water: Once established, it prefers to stay on the dry side
  • USDA Zones 4-8: Can handle both cold winters and hot summers

Garden Design Ideas

If you do manage to responsibly source this rare beauty, it’s perfect for:

  • Rock gardens where it can nestle between stones
  • Alpine gardens that mimic high-elevation conditions
  • Native plant gardens focused on Great Basin species
  • Xeriscaped areas that celebrate drought-tolerant plants

Wildlife and Pollinator Benefits

Despite its small size, smooth prickly phlox punches above its weight when it comes to supporting wildlife. Its tubular flowers are perfectly sized for small native bees and butterflies, making it a valuable addition to pollinator gardens – when responsibly sourced, of course.

The Bottom Line

Smooth prickly phlox represents both an opportunity and a responsibility. If you’re experienced with challenging native plants and passionate about conservation, growing this species can be your way of contributing to its survival. However, the key word here is responsibly – never collect from wild populations, and always work with reputable sources.

For most gardeners, supporting conservation efforts for this species and choosing other native Great Basin plants might be the most helpful approach. Sometimes the best way to love a rare plant is to admire it from afar while supporting the organizations working to protect it in the wild.

Smooth Prickly Phlox

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

Linanthus Benth. - linanthus

Species

Linanthus glabrum (R. Patt. & Yoder-Will.) J.M. Porter & L.A. Johnson - smooth prickly phlox

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