I’ve had my fair share of run-ins with Commelina Communis, commonly called Asiatic Dayflower. It’s one of those plants you either quietly admire or spend hours yanking from your garden beds. Let’s break it down in my own words—simple, direct, and useful.
What Is Commelina Communis?
Commelina Communis is a fast-growing herbaceous annual in the Commelinaceae family. It’s native to East Asia but has spread far beyond, now considered invasive in parts of North America and Europe.
This plant gets its common name—Asiatic Dayflower—from its fleeting blooms. The flowers open in the morning and fade by afternoon. Each one has two large sky-blue petals and a smaller white one underneath. It’s a curious, unforgettable little bloom.
In my experience, it shows up uninvited but commands attention with its vivid color and strange structure. It thrives in moist soils, partial sun, and disturbed areas—basically anywhere you don’t want it.
Is Commelina Communis Invasive?
Yes, absolutely. In most temperate zones, Commelina Communis behaves aggressively. It spreads via seeds and creeping stems that root at the nodes. I’ve seen it colonize shady flower beds, vegetable gardens, and even cracks in concrete.
Controlling it isn’t easy. Regular hand-pulling works if you catch it early. If it goes to seed, you’re in for a season-long battle. It’s best to weed before it flowers, which happens quickly and often.
It’s listed on invasive plant watchlists in several U.S. states. Its resilience and adaptability allow it to outcompete native groundcovers like Tradescantia Virginiana or Viola Sororia.
How Does It Compare to Spiderwort (Tradescantia)?
People often confuse Commelina Communis with Tradescantia, especially Tradescantia Ohiensis or Tradescantia Virginiana. Both share blue flowers and similar-looking leaves.
But here’s how I tell them apart:
- Flowers: Commelina Communis has two prominent blue petals; Tradescantia has three uniform petals.
- Growth Habit: Commelina sprawls low and weedy; Tradescantia grows upright and clumping.
- Time of Bloom: Commelina blooms just for a few hours; Tradescantia’s blooms last a full day.
In a garden, Tradescantia feels intentional. Commelina feels like a sneaky intruder. Though both belong to Commelinaceae, only one is welcome in my beds.
Can Commelina Communis Be Useful?
Surprisingly, yes. In traditional Chinese medicine, it’s used for treating sore throats and fevers. The plant contains flavonoids, phenolic compounds, and antioxidants. Some even grow it deliberately for its medicinal and ornamental value.
I personally admire the flowers but wouldn’t recommend letting it spread. Its usefulness doesn’t outweigh its invasiveness.
Also, it’s used as a natural dye. The brilliant blue pigment is water-soluble and ephemeral—artists use it for its impermanence.
Is It Safe for Pets or People?
From what I’ve read and experienced, Commelina Communis isn’t toxic to dogs, cats, or humans. I’ve never had any issues with pets chewing on it. But that doesn’t mean it’s edible. It’s not listed among common edible wild plants.
Unlike Commelina Erecta (White Mouth Dayflower), which is native to North America and occasionally used as forage, C. Communis is better left untouched.
How Do I Get Rid of Commelina Communis?
Here’s what’s worked for me:
- Early Hand-Pulling – Before flowering or rooting at nodes.
- Mulching – Smothers new shoots.
- Herbicide (Spot Treatment) – Only as a last resort.
- Regular Monitoring – This plant is sneaky. One missed plant leads to dozens.
I never compost the pulled plants—they often root again. I bag them and toss them out with yard waste.
Why Is It Called “Dayflower”?
Because the blooms only last a single day—less, actually. Morning to mid-day, then they wilt. This ephemeral beauty is linked to plant circadian rhythms, phototropism, and humidity levels. It’s fascinating to observe how such a delicate structure hides such botanical complexity.
Does Commelina Communis Have Any Ecological Role?
Interestingly, yes. It attracts small pollinators like sweat bees, hoverflies, and tiny solitary bees. In wild spaces, it can act as a temporary groundcover where native plants have been disturbed.
However, I’ve found that its ability to spread often outweighs its benefit. It’s a textbook ruderal species—fast colonizer, low-value competitor.
Is It Related to Daylilies?
Nope. It’s easy to assume so based on the name “dayflower,” but Hemerocallis (daylily) is in the Asphodelaceae family, not Commelinaceae.
Daylilies are large, fleshy-rooted perennials. Commelina Communis is a spindly annual with tiny blooms and no tuberous storage roots.
Final Thoughts from My Garden
Commelina Communis is a paradox. It’s beautiful but invasive, useful but annoying, simple yet ecologically persistent.
If you’re managing a native plant garden or trying to restore habitat, it’s a nuisance. But if you love unusual flowers and botanical quirks, you might find joy in its blue petals.
If i die, water my plants!
