North America Native Plant

Gray’s Broomrape

Botanical name: Orobanche californica grayana

USDA symbol: ORCAG2

Life cycle: annual

Habit: forb

Native status: Native to the lower 48 states  

Synonyms: Orobanche californica Cham. & Schltdl. var. grayana (G. Beck) Cronquist (ORCAG3)  âš˜  Orobanche grayana G. Beck (ORGR4)   

Gray’s Broomrape: A Fascinating but Uncultivatable Native Wildflower If you’ve stumbled across Gray’s broomrape (Orobanche californica grayana) in your research of native plants, you might be wondering if this intriguing wildflower belongs in your garden. Here’s the thing: while this annual forb is indeed native to the western United States, ...

Rare plant alert!

Region: Conservation status by state

Status: S4T3T4: 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. ⚘ Apparently Secure: Uncommon but not rare, and usually widespread. Possibly cause for longterm concern. Typically more than 100 occurrences in the state or more than 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 ⚘

Gray’s Broomrape: A Fascinating but Uncultivatable Native Wildflower

If you’ve stumbled across Gray’s broomrape (Orobanche californica grayana) in your research of native plants, you might be wondering if this intriguing wildflower belongs in your garden. Here’s the thing: while this annual forb is indeed native to the western United States, it’s definitely not your typical garden plant candidate. Let me explain why, and what makes this little-known species so unique.

What Makes Gray’s Broomrape So Special (and Tricky)

Gray’s broomrape is what botanists call a parasitic plant, which means it doesn’t play by the usual gardening rules. Unlike the sun-loving perennials and self-sufficient annuals we’re used to growing, this forb actually depends entirely on other plants for survival. It attaches to the roots of host plants and draws all its nutrients from them, which is why you’ll never see it sold at your local nursery.

This fascinating adaptation has allowed Gray’s broomrape to thrive in specific ecological niches across California, Idaho, Nevada, Oregon, and Washington, where it quietly goes about its parasitic business in natural plant communities.

Why You Can’t (and Shouldn’t) Grow Gray’s Broomrape

Here are the main reasons this native wildflower isn’t suited for home cultivation:

  • Parasitic nature: It requires specific host plants to survive, making independent cultivation impossible
  • Conservation concerns: With a global conservation status indicating some level of rarity, it’s better left in its natural habitat
  • Limited aesthetic appeal: As parasitic plants go, broomrapes aren’t particularly showy or ornamental
  • Complex ecological relationships: It depends on intricate natural systems that can’t be replicated in gardens

Its Role in Natural Ecosystems

While Gray’s broomrape might not be garden material, it plays an important role in western North American ecosystems. As an annual forb, it completes its life cycle within a single growing season, timing its emergence and reproduction with the availability of suitable host plants and favorable conditions.

The plant’s parasitic lifestyle might seem harsh, but it’s actually part of the complex web of relationships that keep natural plant communities in balance. Some parasitic plants even help maintain plant diversity by preventing any single species from becoming too dominant.

Better Native Alternatives for Your Garden

If you’re interested in supporting western native plants in your landscape, there are countless beautiful and garden-worthy alternatives that share Gray’s broomrape’s native range:

  • California poppies for vibrant orange blooms
  • Lupines for stunning flower spikes
  • Native penstemons for pollinator-friendly flowers
  • Western columbines for delicate, unique blooms

Appreciating Gray’s Broomrape in the Wild

The best way to appreciate this uncommon native is to keep an eye out for it during hikes and nature walks in its native range. If you’re lucky enough to spot it, take a moment to marvel at the fascinating world of plant relationships it represents. Just remember to observe and photograph only – this is one native that’s best left exactly where you find it.

Sometimes the most interesting native plants are the ones that remind us that nature is far more complex and interconnected than our gardens can ever capture. Gray’s broomrape is definitely one of those plants – fascinating to learn about, but perfectly content living its parasitic lifestyle in the wild where it belongs.

Gray’s Broomrape

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

Orobanchaceae Vent. - Broom-rape family

Genus

Orobanche L. - broomrape

Species

Orobanche californica Cham. & Schltdl. - California broomrape

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