North America Native Plant

Phlox Heliotrope

Botanical name: Heliotropium convolvulaceum var. californicum

USDA symbol: HECOC

Life cycle: annual

Habit: forb

Native status: Native to the lower 48 states  

Synonyms: Euploca convolvulacea Nutt. ssp. californica (Greene) Abrams (EUCOC2)  âš˜  Heliotropium californicum Greene (HECA26)   

Phlox Heliotrope: A Rare Native Annual Worth Knowing Meet the phlox heliotrope, a charming little wildflower that might just be one of the Southwest’s best-kept secrets. This delicate annual belongs to the borage family and represents a unique piece of our native plant heritage that deserves more attention from conservation-minded ...

Rare plant alert!

Region: Conservation status by state

Status: S5T3T4: Status is uncertain but is somewhere between the following rankings: Subspecies or variety is 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. ⚘ Subspecies or varieties is apparently secure: Uncommon but not rare, and usually widespread. Possibly cause for longterm concern. Typically more than 100 occurrences in the region or more than 10,000 individuals ⚘ Secure: At very low or no risk of extinction in the jurisdiction due to a very extensive range, abundant populations or occurrences, with little to no concern from declines or threats. ⚘

Phlox Heliotrope: A Rare Native Annual Worth Knowing

Meet the phlox heliotrope, a charming little wildflower that might just be one of the Southwest’s best-kept secrets. This delicate annual belongs to the borage family and represents a unique piece of our native plant heritage that deserves more attention from conservation-minded gardeners.

What Makes Phlox Heliotrope Special

Phlox heliotrope (Heliotropium convolvulaceum var. californicum) is a native forb – basically a fancy botanical term for a soft-stemmed flowering plant that’s not a grass. As an annual, it completes its entire life cycle in just one growing season, making it a fascinating example of nature’s live fast, bloom bright philosophy.

This plant has quite the collection of scientific aliases too, including Euploca convolvulacea ssp. californica and Heliotropium californicum, showing just how much botanists have debated its proper classification over the years.

Where You’ll Find It Growing Wild

Phlox heliotrope calls the American Southwest home, naturally occurring across Arizona, California, and Colorado. It’s a true native of the lower 48 states, having evolved alongside the region’s other desert and semi-arid plant communities over thousands of years.

A Word About Conservation

Here’s where things get important: phlox heliotrope has a global conservation status of S5T3T4, which indicates this variety faces some level of conservation concern. While it’s not critically endangered, it’s not exactly common either. This means if you’re interested in growing it, you’ll want to be extra careful about sourcing.

The responsible approach: Only obtain seeds or plants from reputable native plant nurseries that can verify their stock comes from ethically collected, locally-appropriate sources. Never collect from wild populations.

Garden Potential and Considerations

As a native annual forb, phlox heliotrope could potentially fit into:

  • Native plant gardens focused on southwestern flora
  • Wildflower meadows or naturalized areas
  • Educational or conservation-focused landscapes
  • Xerophytic (drought-tolerant) garden designs

However, there’s a catch – detailed growing information for this specific variety is surprisingly scarce in gardening literature. This likely reflects both its specialized habitat requirements and its conservation status.

The Reality of Growing Rare Natives

While phlox heliotrope represents an authentic piece of southwestern botanical heritage, its rarity and the lack of detailed cultivation information make it a challenging choice for most home gardeners. Unless you’re specifically working on habitat restoration or have experience with rare native annuals, you might want to consider more readily available native alternatives that provide similar ecological benefits.

Supporting Native Plant Communities

If phlox heliotrope has captured your interest, consider these approaches:

  • Support local conservation organizations working to protect native plant habitats
  • Choose other native southwestern annuals that are more readily available and well-documented
  • Visit botanical gardens or natural areas where you might observe this species in its natural setting
  • Participate in citizen science projects that help track rare native plant populations

Sometimes the best way to appreciate a rare native plant is to ensure its wild populations remain healthy and thriving. By choosing abundant native alternatives for our gardens and supporting conservation efforts, we help protect botanical treasures like phlox heliotrope for future generations to discover and admire.

Phlox Heliotrope

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

Lamiales

Family

Boraginaceae Juss. - Borage family

Genus

Heliotropium L. - heliotrope

Species

Heliotropium convolvulaceum (Nutt.) A. Gray - phlox heliotrope

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