North America Native Plant

Harlequin Phacelia

Botanical name: Phacelia howelliana

USDA symbol: PHHO2

Life cycle: annual

Habit: forb

Native status: Native to the lower 48 states  

Harlequin Phacelia: A Rare Desert Gem Worth Protecting Meet the harlequin phacelia (Phacelia howelliana), one of the Southwest’s most elusive wildflowers. This little-known annual forb might not be on every gardener’s wishlist, but its story is one of resilience, rarity, and the delicate balance of desert ecosystems. What Makes Harlequin ...

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) ⚘

Harlequin Phacelia: A Rare Desert Gem Worth Protecting

Meet the harlequin phacelia (Phacelia howelliana), one of the Southwest’s most elusive wildflowers. This little-known annual forb might not be on every gardener’s wishlist, but its story is one of resilience, rarity, and the delicate balance of desert ecosystems.

What Makes Harlequin Phacelia Special?

The harlequin phacelia is a true American native, belonging to the diverse Phacelia genus in the borage family. As an annual forb, it completes its entire life cycle in just one growing season, making the most of brief favorable conditions in its harsh desert home.

This plant is what botanists call a forb – essentially a non-woody flowering plant that puts all its energy into reproduction rather than building permanent woody structures. Think of it as nature’s version of live fast, bloom bright.

Where Does It Call Home?

Harlequin phacelia has one of the most restricted ranges you’ll find in North American wildflowers. This rare beauty is found only in Arizona and Utah, where it clings to existence in very specific desert habitats. We’re talking about a plant so geographically picky that botanists have documented only 6 to 20 known locations where it still grows wild.

The Rarity Reality Check

Here’s where things get serious: harlequin phacelia carries a Global Conservation Status of S2, which means it’s considered imperiled. In plain English? This plant is in trouble. With typically only 1,000 to 3,000 individual plants remaining in the wild, every single harlequin phacelia matters.

This rarity status means that if you’re lucky enough to encounter seeds or plants, they must come from completely ethical, conservation-minded sources. Wild collection is absolutely off-limits – we’re talking about a species that can’t afford to lose even a few individuals.

Should You Grow Harlequin Phacelia?

The short answer is: only if you can source it responsibly and you’re committed to conservation. Here’s the thing – this isn’t a plant you’ll find at your local nursery, and that’s probably for the best. Its extreme rarity means that any cultivation should be part of conservation efforts rather than casual gardening.

If you’re passionate about rare plant conservation and have access to ethically sourced seeds through botanical institutions or conservation programs, harlequin phacelia could be part of a specialized native plant collection focused on preserving genetic diversity.

The Mystery of Growing Conditions

Given its limited distribution in Arizona and Utah deserts, we can make educated guesses about what harlequin phacelia needs to thrive:

  • Excellent drainage – desert plants despise waterlogged soil
  • Full sun exposure
  • Hot, dry summers and cool winters typical of high desert regions
  • Sandy or rocky, nutrient-poor soils
  • Minimal supplemental watering once established

However, because of its rarity, there’s limited documented experience with cultivation requirements. Any growing attempts should be considered experimental and approached with the reverence due to an imperiled species.

Conservation Over Cultivation

Rather than focusing on how to grow harlequin phacelia in your garden, consider how you can support its conservation in the wild. Supporting organizations that protect desert habitats, participating in citizen science projects, and choosing other native Phacelia species for your garden are all ways to honor this rare plant’s existence.

If you’re drawn to the Phacelia genus (and who wouldn’t be – they’re fantastic pollinator plants!), consider more common relatives like wild heliotrope (Phacelia distans) or desert bells (Phacelia campanularia) that can bring similar ecological benefits to your native landscape without conservation concerns.

The Bigger Picture

Harlequin phacelia reminds us that not every native plant is meant for widespread cultivation. Sometimes, the best thing we can do for a species is protect its wild habitat and resist the urge to bring it into our gardens. In a world where biodiversity is under constant pressure, showing restraint can be its own form of stewardship.

This little annual forb may be rare and mysterious, but its story highlights the incredible diversity hidden in America’s desert landscapes – and the responsibility we all share in protecting these botanical treasures for future generations.

Harlequin 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 howelliana N.D. Atwood - harlequin phacelia

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