North America Native Plant

Grassland Tarweed

Botanical name: Deinandra increscens increscens

USDA symbol: DEINI8

Life cycle: annual

Habit: forb

Native status: Native to the lower 48 states  

Synonyms: Hemizonia increscens (H.M. Hall ex D.D. Keck) Tanowitz (HEIN5)  âš˜  Hemizonia increscens (H.M. Hall ex D.D. Keck) Tanowitz ssp. increscens (HEINI)  âš˜  Hemizonia paniculata A. Gray ssp. increscens H.M. Hall ex D.D. Keck (HEPAI)   

Grassland Tarweed: A Humble California Native with Big Garden Benefits Meet grassland tarweed (Deinandra increscens increscens), a charming little California native that might not win any beauty contests, but definitely deserves a spot in your native garden. This unassuming annual wildflower has been quietly doing its thing in California’s grasslands ...

Grassland Tarweed: A Humble California Native with Big Garden Benefits

Meet grassland tarweed (Deinandra increscens increscens), a charming little California native that might not win any beauty contests, but definitely deserves a spot in your native garden. This unassuming annual wildflower has been quietly doing its thing in California’s grasslands for centuries, and it’s ready to bring some authentic Golden State character to your landscape.

What is Grassland Tarweed?

Grassland tarweed is an annual forb—basically a non-woody flowering plant that completes its entire life cycle in one growing season. Don’t let the tarweed name scare you off; it simply refers to the plant’s slightly sticky, aromatic foliage. This native Californian belongs to the sunflower family and produces small, cheerful yellow daisy-like flowers that may be modest in size but are mighty in their ecological impact.

You might also encounter this plant under its former scientific names, including Hemizonia increscens, as botanists have shuffled it around the taxonomic family tree over the years.

Where Does Grassland Tarweed Call Home?

This California endemic is naturally found throughout the Golden State, where it thrives in grasslands, open areas of the Central Valley, and adjacent foothills. It’s perfectly adapted to California’s Mediterranean climate and has been a cornerstone of the state’s native grassland communities for generations.

Why Grow Grassland Tarweed?

While grassland tarweed might not have the showstopping flowers of some garden favorites, it brings several valuable qualities to your landscape:

  • True California native: Supports local ecosystems and requires minimal resources once established
  • Pollinator magnet: Those small yellow flowers are beloved by native bees and beneficial insects
  • Low maintenance: As an annual, it does its own thing with minimal fuss
  • Drought tolerance: Perfect for water-wise gardening
  • Natural reseeding: Establishes self-sustaining populations in suitable conditions

Perfect Garden Situations

Grassland tarweed shines in:

  • Native California gardens and restoration projects
  • Wildflower meadows and naturalized areas
  • Drought-tolerant landscapes
  • Areas where you want low-maintenance ground cover
  • Pollinator gardens focused on native species

Growing Conditions and Care

This easygoing native thrives in USDA hardiness zones 8-10 and prefers:

  • Sunlight: Full sun for best performance
  • Soil: Well-draining soils; tolerates poor, rocky, or clay soils
  • Water: Drought-tolerant once established; minimal summer water needed
  • Space: Allow room for natural spreading and reseeding

Planting and Care Tips

Growing grassland tarweed is refreshingly straightforward:

  • Timing: Direct seed in fall for spring germination, following natural rainfall patterns
  • Seeding: Scatter seeds in prepared areas and lightly rake in
  • Watering: Water until established, then rely on natural rainfall
  • Maintenance: Allow plants to complete their cycle and drop seeds for next year’s crop
  • Patience: Let it naturalize—this plant knows what it’s doing!

The Bottom Line

Grassland tarweed might not be the flashiest plant in your garden, but it’s a hardworking native that delivers authentic California character while supporting local wildlife. If you’re creating a native garden, restoring natural habitat, or simply want a low-maintenance annual that gives back to the ecosystem, this humble tarweed deserves serious consideration. Sometimes the best garden plants are the ones that quietly do their job while asking for very little in return.

Grassland 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

Deinandra Greene - tarweed

Species

Deinandra increscens (H.M. Hall ex D.D. Keck) B.G. Baldw. - grassland tarweed

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