North America Native Plant

Croft’s Bluet

Botanical name: Houstonia croftiae

USDA symbol: HOCR

Life cycle: annual

Habit: forb

Native status: Native to the lower 48 states  

Synonyms: Hedyotis croftiae (Britton & Rusby) Shinners (HECR7)   

Croft’s Bluet: A Rare Texas Treasure Worth Protecting Meet Croft’s bluet (Houstonia croftiae), one of Texas’s most elusive native wildflowers. This tiny annual might not grab headlines like bluebonnets, but for those in the know, it represents something truly special – a rare piece of Texas’s natural heritage that deserves ...

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 ⚘

Croft’s Bluet: A Rare Texas Treasure Worth Protecting

Meet Croft’s bluet (Houstonia croftiae), one of Texas’s most elusive native wildflowers. This tiny annual might not grab headlines like bluebonnets, but for those in the know, it represents something truly special – a rare piece of Texas’s natural heritage that deserves our attention and protection.

What Makes Croft’s Bluet Special?

Croft’s bluet is an annual forb, meaning it’s a soft-stemmed herbaceous plant that completes its entire life cycle in just one growing season. As a member of the coffee family (Rubiaceae), it shares some distant relatives with your morning brew, though this little wildflower is all about delicate beauty rather than caffeine kicks.

You might also see this plant listed under its scientific synonym, Hedyotis croftiae, in older botanical references – but don’t let the name changes confuse you. It’s the same rare Texas native we’re talking about.

Where Does It Call Home?

This bluet is a true Texas endemic, found nowhere else in the world except within the Lone Star State. Its extremely limited range makes it one of the state’s botanical treasures, though exactly where it grows remains somewhat of a mystery due to its rarity.

A Plant That Needs Our Help

Here’s where things get serious: Croft’s bluet has a Global Conservation Status of S3, which means it’s considered vulnerable. With only an estimated 21 to 100 occurrences and between 3,000 to 10,000 individual plants in existence, this species is walking a tightrope toward extinction.

What does this mean for gardeners? While we absolutely want to celebrate and support native Texas plants, Croft’s bluet requires special consideration. If you’re interested in growing this species, it’s crucial that you only obtain seeds or plants from verified, responsibly managed sources that don’t impact wild populations.

Growing Croft’s Bluet: What We Know

Unfortunately, detailed cultivation information for this rare species is limited. As an annual forb, it would theoretically complete its growing cycle within one year, but specific details about:

  • Preferred soil conditions
  • Water requirements
  • Sunlight needs
  • Specific USDA hardiness zones
  • Propagation methods

…are not well-documented in horticultural literature, likely due to the plant’s rarity and limited study.

Should You Grow It?

The honest answer? Probably not, unless you’re part of a legitimate conservation effort. Instead, consider supporting Croft’s bluet and other rare Texas natives by:

  • Growing other native Texas bluets that are more common and readily available
  • Supporting botanical gardens and conservation organizations working to protect rare species
  • Creating habitat for native Texas wildflowers in your own garden
  • Learning about and advocating for the protection of rare native plants

Better Alternatives for Your Garden

If you’re drawn to the idea of growing Texas bluets, consider these more readily available native alternatives:

  • Common bluet (Houstonia pusilla)
  • Summer bluet (Houstonia nigricans)
  • Other native Texas wildflowers that provide similar ecological benefits

These species can give you that delicate wildflower charm while supporting local ecosystems without putting rare species at risk.

The Bigger Picture

Croft’s bluet reminds us that not every native plant is meant for our garden beds – and that’s okay. Sometimes the best way to love a plant is to admire it from afar and work to protect its natural habitat. By choosing more common native alternatives and supporting conservation efforts, we can all play a part in ensuring that future generations might glimpse this rare Texas treasure in the wild where it belongs.

Croft’s Bluet

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

Rubiales

Family

Rubiaceae Juss. - Madder family

Genus

Houstonia L. - bluet

Species

Houstonia croftiae Britton & Rusby - Croft's bluet

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