North America Native Plant

Pennyroyal Leaf Phacelia

Botanical name: Phacelia glechomifolia

USDA symbol: PHGL13

Life cycle: annual

Habit: forb

Native status: Native to the lower 48 states  

Pennyroyal Leaf Phacelia: A Rare Arizona Native Worth Protecting If you’re a native plant enthusiast looking for something truly special for your Arizona garden, you might have stumbled upon pennyroyal leaf phacelia (Phacelia glechomifolia). This little-known annual is one of those botanical gems that makes you feel like you’ve discovered ...

Rare plant alert!

Region: Conservation status by state

Status: S3: Status is uncertain but is somewhere between the following rankings: 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 ⚘

Pennyroyal Leaf Phacelia: A Rare Arizona Native Worth Protecting

If you’re a native plant enthusiast looking for something truly special for your Arizona garden, you might have stumbled upon pennyroyal leaf phacelia (Phacelia glechomifolia). This little-known annual is one of those botanical gems that makes you feel like you’ve discovered a secret—and in many ways, you have.

What Makes This Plant Special

Pennyroyal leaf phacelia is a native Arizona annual that belongs to the diverse Phacelia genus, known for their often spectacular spring wildflower displays. As a forb—essentially a non-woody flowering plant—this species represents the kind of ephemeral beauty that makes desert springs so magical.

What sets this particular phacelia apart isn’t just its rarity, but its story. This plant is classified as having a Global Conservation Status of S3, which means it’s considered vulnerable. In plant conservation terms, this typically means there are only 21 to 100 known occurrences or between 3,000 and 10,000 individual plants in existence. That’s pretty exclusive company!

Where You’ll Find It (Or Won’t)

This phacelia calls Arizona home and, as far as we know, only Arizona. Its limited geographic distribution is part of what makes it so special—and so vulnerable. When a plant is found in only one state, every population becomes critically important for the species’ survival.

Should You Grow Pennyroyal Leaf Phacelia?

Here’s where things get interesting. As a responsible gardener, you absolutely should consider growing rare native plants like pennyroyal leaf phacelia—but with some important caveats.

The Case for Growing It

  • Supporting native biodiversity in your landscape
  • Helping preserve a vulnerable species through cultivation
  • Adding a truly unique plant to your collection
  • Contributing to conservation efforts

The Responsible Approach

Never collect from the wild. This cannot be stressed enough. With only limited populations in existence, removing plants or seeds from wild populations could seriously harm the species’ survival chances.

Instead, seek out seeds or plants from reputable native plant nurseries or conservation organizations that work with responsibly sourced material. Some botanical gardens and native plant societies also maintain conservation seed programs for rare species.

Growing Challenges and Unknowns

Here’s where pennyroyal leaf phacelia becomes a bit of a gardening adventure. Because this plant is so rare and poorly studied, specific growing information is limited. We know it’s an annual, which means it completes its entire life cycle in one growing season, but details about its specific soil preferences, water needs, or optimal planting conditions aren’t well documented.

This makes it both a challenge and an opportunity for dedicated native plant gardeners. Growing rare species often involves some trial and error, but successful cultivation could contribute valuable information to conservation efforts.

Alternative Phacelia Options

If you can’t source pennyroyal leaf phacelia responsibly, consider other Arizona-native Phacelia species that are more readily available. The genus includes many beautiful and pollinator-friendly options that can give you that desert wildflower experience while supporting local ecosystems.

The Bottom Line

Pennyroyal leaf phacelia represents both an opportunity and a responsibility. If you can source it ethically, growing this rare Arizona native could be a meaningful way to support plant conservation while adding something truly special to your garden. Just remember—with great rarity comes great responsibility. Every plant counts when you’re dealing with a vulnerable species, so choose your sources wisely and garden with conservation in mind.

Sometimes the most rewarding plants to grow are the ones that make us think beyond our own gardens to the bigger picture of plant conservation and biodiversity protection.

Pennyroyal Leaf Phacelia

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

Hydrophyllaceae R. Br. - Waterleaf family

Genus

Phacelia Juss. - phacelia

Species

Phacelia glechomifolia A. Gray - pennyroyal leaf phacelia

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