North America Native Plant

Flagstaff Beardtongue

Botanical name: Penstemon nudiflorus

USDA symbol: PENU

Life cycle: perennial

Habit: forb

Native status: Native to the lower 48 states  

Flagstaff Beardtongue: A Rare Arizona Native Worth Growing Responsibly If you’re looking to add a touch of Arizona’s wild beauty to your garden, the Flagstaff beardtongue (Penstemon nudiflorus) might just be the perfect choice. This charming little native perennial brings both ecological value and understated elegance to the right landscape—but ...

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 ⚘

Flagstaff Beardtongue: A Rare Arizona Native Worth Growing Responsibly

If you’re looking to add a touch of Arizona’s wild beauty to your garden, the Flagstaff beardtongue (Penstemon nudiflorus) might just be the perfect choice. This charming little native perennial brings both ecological value and understated elegance to the right landscape—but there’s an important catch we need to talk about first.

What Makes Flagstaff Beardtongue Special?

Flagstaff beardtongue is a true Arizona original, found naturally only in the Grand Canyon State. This herbaceous perennial belongs to the penstemon family, known for their distinctive tubular flowers that seem tailor-made for hummingbird beaks. As a forb (basically a fancy term for a soft-stemmed flowering plant), it adds delicate texture to gardens without the bulk of woody shrubs.

What really sets this plant apart is its rarity. With a Global Conservation Status of S2S3, Flagstaff beardtongue is considered uncommon to somewhat common in its limited range. This makes it both a gardening treasure and a conservation concern.

Where Does It Call Home?

As its common name suggests, this penstemon is native to Arizona, particularly around the Flagstaff region. Its natural habitat gives us clues about what it needs to thrive in our gardens—think high desert conditions with plenty of drainage and moderate moisture.

A Important Note About Rarity

Before we dive into growing tips, let’s address the elephant in the room: this plant’s conservation status. Because Flagstaff beardtongue has limited distribution and is considered uncommon, it’s crucial that any plants you acquire come from responsible sources. This means:

  • Purchase only from reputable native plant nurseries
  • Never collect from wild populations
  • Look for nursery-propagated plants with proper documentation
  • Consider this plant an investment in conservation

Garden Appeal and Design Role

In the garden, Flagstaff beardtongue serves as a lovely accent plant rather than a showstopper. Its tubular flowers, typically in shades of purple to blue, create clusters of color that attract pollinators without overwhelming smaller spaces. The plant works beautifully in:

  • Rock gardens and xeriscapes
  • Native plant collections
  • Pollinator gardens focused on southwestern species
  • Natural-style landscapes that mirror Arizona’s high desert

Pollinator and Wildlife Benefits

Like most penstemons, Flagstaff beardtongue is a pollinator magnet. Its tubular flowers are perfectly shaped for hummingbirds, while bees and butterflies also find them irresistible. By growing this rare native, you’re not just adding beauty to your garden—you’re supporting local ecosystems and providing crucial habitat for Arizona’s native pollinators.

Growing Conditions and Care

The good news is that once you’ve sourced your plant responsibly, Flagstaff beardtongue is relatively easy to grow. Here’s what it needs:

Hardiness: Suitable for USDA zones 4-8, making it surprisingly cold-tolerant for a desert native.

Sun Requirements: Full sun to partial shade, though it performs best with morning sun and some afternoon protection in hotter climates.

Soil Needs: Well-draining soil is absolutely essential. Heavy clay or waterlogged conditions will quickly kill this plant. Sandy or rocky soils work beautifully.

Water Requirements: Drought-tolerant once established, but appreciates occasional deep watering during extreme dry spells. Overwatering is more dangerous than underwatering.

Planting and Care Tips

Getting your Flagstaff beardtongue off to a good start sets the stage for years of low-maintenance beauty:

  • Plant in fall or early spring when temperatures are moderate
  • Improve heavy soils with coarse sand or gravel for drainage
  • Space plants according to their mature size (check with your nursery for specific dimensions)
  • Water regularly the first year to establish roots, then reduce frequency
  • Deadhead spent flowers to encourage more blooms
  • Avoid fertilizing—native plants typically don’t need it and may actually grow poorly in rich soils

The Bottom Line

Flagstaff beardtongue is a wonderful choice for Arizona gardeners who want to grow something truly special while supporting conservation efforts. Its rarity makes it a responsibility as much as a pleasure, but for gardeners committed to native plants and ecological stewardship, it’s absolutely worth seeking out from responsible sources.

Just remember: this isn’t a plant for impulse buying or casual gardening. It’s a commitment to preserving Arizona’s natural heritage, one garden at a time. If you’re up for that challenge, you’ll be rewarded with a unique native that connects your garden to the wild landscapes of the Grand Canyon State.

Flagstaff Beardtongue

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

Penstemon Schmidel - beardtongue

Species

Penstemon nudiflorus A. Gray - Flagstaff beardtongue

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