North America Native Plant

Howell’s Broomrape

Botanical name: Orobanche valida howellii

USDA symbol: ORVAH

Life cycle: annual

Habit: forb

Native status: Native to the lower 48 states  

Howell’s Broomrape: A Fascinating but Uncultivatable Native Parasitic Plant Meet Howell’s broomrape (Orobanche valida howellii), one of California’s more mysterious native plants that you definitely won’t find at your local garden center – and for good reason! This annual forb belongs to a fascinating group of plants that have given ...

Rare plant alert!

Region: Conservation status by state

Status: S3T3: 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 ⚘ 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. ⚘

Howell’s Broomrape: A Fascinating but Uncultivatable Native Parasitic Plant

Meet Howell’s broomrape (Orobanche valida howellii), one of California’s more mysterious native plants that you definitely won’t find at your local garden center – and for good reason! This annual forb belongs to a fascinating group of plants that have given up the whole photosynthesis thing in favor of a more, shall we say, dependent lifestyle.

What Makes This Plant So Unusual?

Howell’s broomrape is what botanists call a parasitic plant, meaning it has evolved to live entirely off other plants rather than making its own food through photosynthesis. As an annual forb (a non-woody plant that completes its life cycle in one year), this California native has developed one of nature’s most specialized survival strategies.

The plant lacks the typical green foliage you’d expect from most plants, instead producing stems and flowers that emerge directly from the roots of its unsuspecting host plants. It’s like nature’s version of a botanical freeloader – but one that plays an important role in its ecosystem!

Where You’ll Find It (If You’re Lucky)

This native species calls California home, though spotting one in the wild is quite the botanical treasure hunt. Howell’s broomrape has a somewhat uncertain conservation status, which adds to its mystique and makes it all the more special when encountered by lucky hikers and botanists.

Why You Can’t (and Shouldn’t) Grow It in Your Garden

Here’s where we break some hearts: Howell’s broomrape simply cannot be cultivated in typical garden settings. Here’s why:

  • It requires specific host plants to survive – no host, no broomrape
  • The complex relationship between parasite and host is nearly impossible to replicate in cultivation
  • Its potentially rare status means we should leave wild populations undisturbed
  • It offers no ornamental value for traditional landscaping

Its Role in Nature’s Grand Design

While you might think being a parasitic plant makes Howell’s broomrape the villain of the botanical world, it actually serves important ecological functions. Parasitic plants can help control dominant plant species, create microhabitat diversity, and contribute to the complex web of relationships that make ecosystems resilient.

Some parasitic plants also provide nectar and pollen for specialized insects, though specific information about Howell’s broomrape’s pollinator relationships remains limited in scientific literature.

What This Means for Native Plant Enthusiasts

If you’re passionate about supporting California native plants, the best thing you can do for Howell’s broomrape is to:

  • Appreciate it from a distance if you’re fortunate enough to spot it in the wild
  • Support habitat conservation efforts in California
  • Choose other California natives for your garden that support similar ecosystems
  • Spread awareness about the importance of parasitic plants in natural communities

The Bottom Line

Howell’s broomrape represents one of nature’s most specialized survival strategies, but it’s definitely not destined for garden cultivation. Instead of trying to grow this fascinating parasite, consider it a reminder of the incredible diversity and complexity of California’s native plant communities. Sometimes the most interesting plants are the ones we can only admire in their natural habitats – and that’s perfectly okay!

For your native garden, focus on the many other wonderful California natives that will thrive in cultivation and support local wildlife. Leave the broomrapes to do their mysterious work in the wild, where they belong.

Howell’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 valida Jeps. - Rock Creek broomrape

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