Commelina: The Blue Dayflower That’s Making Waves in California Gardens
If you’ve spotted a charming little plant with bright blue three-petaled flowers popping up in California gardens, you’ve likely encountered commelina (Commelina coelestis). This perennial forb might not be a California native, but it’s certainly made itself at home in the Golden State, bringing a splash of azure beauty to landscapes across the region.
What Is Commelina?
Commelina coelestis is a herbaceous perennial that belongs to the spiderwort family. As a forb, it’s a non-woody plant that dies back to the ground each year but returns from its roots. The plant produces delicate blue flowers that typically open in the morning and close by afternoon – earning it the nickname dayflower in some circles.
Where You’ll Find It Growing
Originally hailing from Central and South America (particularly Mexico and Guatemala), commelina has established itself as a naturalized species in California. It’s considered a non-native plant that reproduces on its own in the wild and has shown a tendency to persist in suitable habitats.
The Visual Appeal
What makes commelina attractive to gardeners? Here are its standout features:
- Vibrant blue three-petaled flowers that seem to glow in morning light
- Heart-shaped, succulent-like leaves that create attractive foliage
- Low-growing, spreading habit perfect for groundcover
- Blooms throughout much of the growing season
Garden Role and Design Uses
Commelina works well in several garden situations:
- Groundcover in informal garden areas
- Border plantings along pathways
- Container gardens and hanging baskets
- Cottage garden settings where a relaxed feel is desired
Growing Conditions and Care
One of commelina’s appealing qualities is its relatively easy-going nature. Here’s what it needs to thrive:
- Light: Partial shade to full sun (morning sun with afternoon shade is ideal)
- Soil: Moist, well-draining soil with average fertility
- Water: Regular watering, especially during dry periods
- Hardiness: Suitable for USDA zones 8-11
Planting and Maintenance Tips
Getting started with commelina is straightforward:
- Plant in spring after the last frost
- Space plants about 12 inches apart for groundcover use
- Water regularly, especially during establishment
- Deadhead spent flowers to encourage more blooms
- Be aware that it self-seeds readily and may spread
Pollinator and Wildlife Value
While not extensively documented, commelina flowers do attract small pollinators, particularly bees. The blue flowers provide nectar for these beneficial insects during the blooming period.
Should You Plant Commelina?
As a non-native species, commelina presents a mixed bag for gardeners. On the positive side, it’s attractive, easy to grow, and provides consistent color. However, since it’s not native to California, it doesn’t support local ecosystems as effectively as indigenous plants would.
If you’re drawn to commelina’s blue flowers and groundcover habit, consider these native alternatives:
- California bluebells (Phacelia campanularia) for similar blue flowers
- Wild ginger (Asarum caudatum) for groundcover in shaded areas
- Beach strawberry (Fragaria chiloensis) for spreading groundcover with white flowers
The Bottom Line
Commelina coelestis offers an easy-care option for gardeners seeking blue flowers and reliable groundcover. While it’s not native to California, it’s not considered invasive either. If you choose to grow it, enjoy its cheerful morning blooms and consider pairing it with native plants to create a more ecologically beneficial garden. Just keep an eye on its spreading tendency and be prepared to manage its self-seeding habit if needed.
