North America Native Plant

Common Tarweed

Botanical name: Centromadia pungens maritima

USDA symbol: CEPUM

Life cycle: annual

Habit: forb

Native status: Native to the lower 48 states  

Synonyms: Hemizonia pungens (Hook. & Arn.) Torr. & A. Gray ssp. maritima (Greene) D.D. Keck (HEPUM)   

Common Tarweed: A Hardy Native Annual for Coastal California Gardens If you’re looking for a low-maintenance native plant that thrives in California’s challenging coastal conditions, common tarweed (Centromadia pungens maritima) might just be your new gardening companion. This unassuming annual herb packs a punch when it comes to supporting local ...

Common Tarweed: A Hardy Native Annual for Coastal California Gardens

If you’re looking for a low-maintenance native plant that thrives in California’s challenging coastal conditions, common tarweed (Centromadia pungens maritima) might just be your new gardening companion. This unassuming annual herb packs a punch when it comes to supporting local wildlife while asking for very little in return.

What is Common Tarweed?

Common tarweed is a native California annual forb that belongs to the sunflower family. Don’t let the name fool you – while it may sound weedy, this plant is actually a valuable native species that has adapted beautifully to coastal environments. As an annual, it completes its entire life cycle in one growing season, but don’t worry about replanting – this clever plant readily self-seeds when happy.

You might also encounter this plant under its former scientific name, Hemizonia pungens ssp. maritima, as botanical classifications sometimes change as scientists learn more about plant relationships.

Where Does Common Tarweed Call Home?

This coastal native is found exclusively in California, where it thrives in salt marshes, coastal grasslands, and other seaside habitats. It’s perfectly adapted to the unique challenges of coastal living – salt spray, sandy soils, and variable moisture levels don’t phase this tough little plant.

Why Grow Common Tarweed?

There are several compelling reasons to consider adding common tarweed to your native plant palette:

  • True California native: Supporting local ecosystems by growing plants that belong here
  • Pollinator magnet: The small yellow flowers attract native bees, beneficial insects, and butterflies
  • Low maintenance: Once established, it requires minimal care and water
  • Salt tolerant: Perfect for coastal properties where salt spray limits plant options
  • Self-seeding: Will naturalize in suitable conditions, reducing replanting needs

Garden Design and Landscape Uses

Common tarweed works beautifully in several garden styles and situations:

  • Native plant gardens: Combines well with other California coastal natives
  • Wildlife gardens: Provides nectar for pollinators and seeds for birds
  • Coastal restoration projects: Helps stabilize soil and restore natural habitat
  • Xeriscapes: Drought tolerance makes it suitable for water-wise landscaping
  • Informal naturalized areas: Perfect for meadow-style plantings

Growing Conditions and Care

The beauty of common tarweed lies in its adaptability and low-maintenance nature. Here’s what this coastal native prefers:

Sunlight: Full sun is essential for healthy growth and flowering

Soil: Well-draining soils are crucial – this plant doesn’t tolerate waterlogged conditions. Sandy or loamy soils work best, and it can handle poor soils that challenge other plants.

Water: Drought-tolerant once established, but benefits from occasional deep watering during dry spells

Climate: Best suited for USDA hardiness zones 9-11, matching coastal California’s mild climate

Planting and Establishment Tips

Getting common tarweed started in your garden is straightforward:

  • Timing: Direct seed in fall for best results, allowing natural winter rains to support germination
  • Seeding: Scatter seeds on prepared soil surface and lightly rake in
  • Spacing: Allow plants room to spread naturally – they’ll find their own preferred spacing
  • Establishment: Provide supplemental water during the first growing season if rainfall is insufficient
  • Maintenance: Once established, minimal care is needed – just allow plants to complete their natural cycle

Wildlife Benefits

Common tarweed is more than just a pretty face – it’s a valuable contributor to local ecosystems. The flowers provide nectar for native bees and butterflies, while the seeds feed birds and small mammals. As a native plant, it has co-evolved relationships with local wildlife that non-native plants simply can’t replicate.

Is Common Tarweed Right for Your Garden?

Consider common tarweed if you’re gardening in coastal California and want to support native ecosystems with minimal effort. It’s particularly valuable for gardeners dealing with challenging coastal conditions like salt spray, sandy soils, or water restrictions. However, if you prefer highly manicured landscapes or live outside its natural range, you might want to explore other native options better suited to your specific location and gardening style.

Remember, the best native plant garden is one that works with your local conditions rather than against them – and common tarweed is perfectly designed to thrive in California’s coastal environments.

Common 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

Centromadia Greene - tarweed

Species

Centromadia pungens (Hook. & Arn.) Greene - common tarweed

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