North America Native Plant

Hayfield Tarweed

Botanical name: Hemizonia congesta tracyi

USDA symbol: HECOT

Life cycle: annual

Habit: forb

Native status: Native to the lower 48 states  

Synonyms: Hemizonia luzulifolia DC. ssp. tracyi Babc. & H.M. Hall (HELUT)  âš˜  Hemizonia tracyi (Babc. & H.M. Hall) D.D. Keck (HETR)   

Hayfield Tarweed: A California Native Worth Knowing If you’re looking to add authentic California character to your native garden, hayfield tarweed (Hemizonia congesta tracyi) might just be the under-the-radar wildflower you’ve been searching for. This annual forb brings a touch of golden sunshine to late summer landscapes, though it’s definitely ...

Rare plant alert!

Region: Conservation status by state

Status: S5T3: 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. ⚘ 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. ⚘

Hayfield Tarweed: A California Native Worth Knowing

If you’re looking to add authentic California character to your native garden, hayfield tarweed (Hemizonia congesta tracyi) might just be the under-the-radar wildflower you’ve been searching for. This annual forb brings a touch of golden sunshine to late summer landscapes, though it’s definitely more wildland wanderer than garden party guest.

What Exactly Is Hayfield Tarweed?

Hayfield tarweed is a native California annual that belongs to the sunflower family. As a forb, it’s an herbaceous plant without woody stems – think of it as nature’s version of a seasonal pop-up shop. This little wildflower typically completes its entire life cycle in one growing season, making the most of California’s Mediterranean climate.

You might also see this plant referenced by its scientific synonyms, including Hemizonia luzulifolia ssp. tracyi or Hemizonia tracyi, depending on which botanical reference you’re consulting. The world of plant taxonomy can be as twisty as a mountain trail!

Where Does It Call Home?

This tarweed is a true California native, found throughout the Golden State’s diverse landscapes. From grasslands to agricultural edges, it has adapted to life in California’s unique climate zones.

Should You Plant It in Your Garden?

Here’s where things get interesting – and a bit complicated. Hayfield tarweed has a conservation status of S5T3, which indicates some level of rarity concern. If you’re considering adding this plant to your garden, it’s crucial to source seeds or plants only from reputable native plant nurseries that practice ethical collection methods.

This isn’t your typical garden center find, and honestly, that’s probably for the best. Hayfield tarweed is more suited to naturalized areas, native plant gardens, or restoration projects rather than formal landscaping.

Garden Role and Landscape Fit

Think of hayfield tarweed as the supporting actor rather than the leading star in your native plant drama. It works best in:

  • Wildflower meadows and naturalized areas
  • Native plant gardens focused on California species
  • Restoration or habitat creation projects
  • Educational gardens showcasing local flora

It’s definitely not the plant for formal borders or high-maintenance landscapes. This is a let it do its thing kind of wildflower.

Wildlife and Pollinator Benefits

While specific pollinator data for this particular subspecies is limited, tarweeds in general are known to support various native bees and small pollinators. As part of California’s native plant community, it likely plays a role in supporting local ecosystem relationships that have developed over thousands of years.

Growing Conditions and Care

If you do decide to grow hayfield tarweed, you’ll want to mimic its natural habitat preferences. Based on its native range and family characteristics, this plant likely thrives in:

  • Full sun locations
  • Well-draining soils, including clay types
  • Areas with minimal summer water (drought-tolerant once established)
  • USDA zones 8-10, typical for California natives

Planting and Care Tips

As an annual, hayfield tarweed completes its life cycle in one season, so timing is everything:

  • Plant seeds in fall or early spring to align with natural rainfall patterns
  • Provide minimal supplemental water – overwatering can be more harmful than helpful
  • Allow plants to self-seed for natural population maintenance
  • Avoid heavy fertilization, which can promote excessive vegetative growth

Remember, this is a plant that evolved to handle California’s dry summers and wet winters, so less intervention is usually more successful.

The Bottom Line

Hayfield tarweed isn’t for every gardener or every garden situation. It’s best suited for those passionate about native plants, ecological restoration, or creating authentic California habitats. If you’re drawn to this plant’s subtle charms and conservation value, just be sure to source it responsibly and give it the naturalized setting where it can truly shine.

For most home gardeners looking for reliable native color, consider more readily available California natives like poppies, lupines, or penstemons. But for the native plant enthusiast seeking something special – and willing to do the responsible sourcing homework – hayfield tarweed offers a genuine piece of California’s botanical heritage.

Hayfield Tarweed

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

Asterales

Family

Asteraceae Bercht. & J. Presl - Aster family

Genus

Hemizonia DC. - tarweed

Species

Hemizonia congesta DC. - hayfield tarweed

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