Coastal Tarweed: California’s Cheerful Late-Season Bloomer
If you’re looking for a native California wildflower that brings sunshine to your garden when most other plants are calling it quits for the season, meet coastal tarweed (Deinandra corymbosa corymbosa). This delightful annual might not win any beauty contests in spring, but come late summer and fall, it transforms into a golden spectacle that both you and local wildlife will absolutely love.
What Makes Coastal Tarweed Special?
Coastal tarweed is a California native that knows how to make an entrance—just not when you’d expect it. While most wildflowers are busy showing off in spring, this clever little forb waits for the cooler days of late summer to burst into bloom with cheerful yellow, daisy-like flowers. It’s like nature’s way of giving us a second spring when we need it most!
This herbaceous annual is endemic to California, where it naturally grows in coastal sage scrub and chaparral communities. You might also know it by its former scientific name, Hemizonia corymbosa, if you’ve encountered it in older gardening references.
Where Does Coastal Tarweed Grow?
Coastal tarweed is a true California native, found primarily along the state’s coastal regions. It thrives in the Mediterranean climate zones and has adapted perfectly to the Golden State’s unique weather patterns.
A Note About Conservation
Before we dive into growing tips, it’s worth noting that coastal tarweed has a conservation status that suggests it may be somewhat vulnerable in the wild. This makes it even more important to include in our native gardens! Just be sure to source your seeds from reputable native plant nurseries that practice responsible collection methods.
Why Your Garden (and Local Wildlife) Will Love It
Here’s where coastal tarweed really shines:
- Pollinator magnet: Those bright yellow flowers are like a beacon for native bees, butterflies, and other beneficial insects
- Late-season interest: Blooms when most other plants are winding down
- Low maintenance: Once established, it’s incredibly drought tolerant
- Self-seeding: Let it go to seed, and you’ll have volunteers next year
- Native habitat support: Helps restore and maintain local ecosystems
Perfect Garden Matches
Coastal tarweed is ideal for:
- Native plant gardens
- Wildflower meadows
- Pollinator gardens
- Drought-tolerant landscapes
- Naturalized areas where you want a wild look
It’s particularly wonderful when planted en masse for a golden carpet effect, or mixed with other California natives for a diverse wildflower display.
Growing Coastal Tarweed: Easy Does It
Climate Zones: USDA zones 9-11 (perfect for California’s Mediterranean climate)
Growing Conditions:
- Sun: Full sun (at least 6 hours daily)
- Soil: Well-draining soil; not fussy about soil type
- Water: Drought tolerant once established; minimal summer water needed
Planting and Care Tips
When to Plant: Fall is ideal for direct seeding, allowing natural winter rains to germinate the seeds.
How to Plant:
- Scatter seeds directly in the garden area
- Lightly rake to ensure good seed-to-soil contact
- No need to bury deeply—these seeds like light
- Water gently if fall rains are delayed
Ongoing Care:
- Water occasionally during establishment (first year)
- Once established, little to no supplemental watering needed
- Allow plants to go to seed for next year’s display
- Cut back spent plants in late fall or early winter
The Bottom Line
Coastal tarweed might not be the flashiest plant in your garden, but it’s definitely one of the most valuable. It offers late-season color when you need it most, supports local wildlife, and requires virtually no maintenance once established. Plus, you’ll be helping to preserve a piece of California’s natural heritage right in your own backyard.
Just remember to source your seeds responsibly, sit back, and wait for that magical late-summer moment when your garden suddenly glows with golden blooms. Trust us—it’s worth the wait!
