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Who says weeds have to be unsightly? The Dayflower, also called the Commelina and closely related to the Spiderwort, is a visually attractive type of weed. So named because its new flowers only last for a single day before withering up at solar noon, this type of weed straddles the line between usefulness and nuisance.

Read on to learn all there is to know about Dayflowers…including why they are classified as weeds, how to identify and rid your landscaping of them, and whether they serve any beneficial purposes.

Closeup of blue dayflowers with yellow stamens.

Why Are Dayflowers Considered A Weed?

The Problem with Dayflowers

Like many common weeds we hear about today, Dayflowers are not necessarily insidious or harmful to the environment, at least in small quantities and controlled numbers. In fact, they have proven to have some medicinal and culinary uses.

However, these flowers are quick to reproduce and spread rapidly over any area where they take root. And they do take root quite ferociously! This unfortunate proliferation is what has earned them their overall weed status.

A group of dayflowers growing among logs.

Where Dayflowers Come From

There are a couple of different Dayflower varieties found commonly in not just the United States, but all over the world. The two most prolific are the Asiatic Dayflower and the Benghali Dayflower. It is thought that these two varieties, now naturalized worldwide, are largely responsible for the majority of Dayflowers you would find in the wild today.

Asiatic Dayflowers are the variety most commonly found growing in the United States. It is speculated they arrived due to colonization and trading, and their rapid growth took care of the rest.

Another couple of Dayflowers you will find in the United States include Virginia Dayflowers, commonly found in the Midwest and eastern portions of the United States. There are also White Mouth Dayflowers, which are native to the United States.

How Dayflowers Spread

Closeups of a blue dayflower blossom.

Dayflowers spread in a number of ways, which is unfortunate for gardeners and landscapers who prefer not to have these weeds around. The most obvious way these weeds proliferate is with the spreading of their seeds. These seeds can take to ground and can lie dormant for years before being stirred up and sprouting.

Dayflowers can also continue to thrive, pollinate, and drop seeds even if the stem is broken off. They will simply grow right back and keep doing their thing. Dayflowers are just an incredibly hardy type of weed that will just keep coming back and keep coming back.

Another way the Dayflower spreads–and this has proven to be perhaps the most annoying and unbelievable for gardeners and landscapers everywhere–is their incredibly hardy and fierce root system. Unlike many types of weeds, these roots don’t lose their luster once you unbury them from the soil.

If you pull up these weeds from your landscaping by the roots and toss them aside, they can simply dig into the soil again wherever their exposed roots touch the soil…and they will, if given just enough time to do it!

How To Identify Dayflowers

A blue dayflower on a long stalk.

Dayflowers can, on occasion, be a little bit tricky to identify, particularly when they first sprout. This weed variety bears some resemblance to wide leaf grass when it first shows its face, so it can be easy to overlook. However, its flowering habit sets it apart from such grasses in short order.

A Dayflower plant can be identified by a day’s worth of watching, if you are feeling patient. There is no hiding how the flowers bloom and then wither in the heat of the day! However, there are a few other distinguishing characteristics of this weed you can use to spot–and then address–its presence in a quick and timely fashion.

Your common Dayflower will emerge in the morning from a green flower sheath, one flower at a time. Each flower boasts three petals–usually two large blue petals above and a smaller white or green-tinged petal on the bottom.

An Asiatic dayflower blossom with blue petals and white petals.
Asiatic dayflower.

Dayflowers contain six stamens, with three sterile ones being on short stems and three longer ones. The longer stamens are the plant’s pollinators.

You will often spot common Dayflowers in the wild in landscapes where the soil is disturbed. This includes alongside waterways, ditches, bottomlands, roadsides and beside railroads, as well as in waste places, gardens, and cultivated fields.

White Mouth Dayflowers, meanwhile, are more often found in drier areas, such as in prairies and grasslands.

How to Get Rid Of Dayflowers

Dayflowers on tall leafy stalks.


The best way to remove Dayflowers from your landscaping or garden is by hand. Pulling the weeds out by the roots, bagging them, and disposing of the bag is the best way to ensure you get them out and keep them out. This reduces the risk of the roots taking root in the soil again elsewhere.

Try to weed out Dayflowers when the soil is moist and workable, and before the weeds are ready to drop their seeds. Otherwise, you run the risk of the stems cracking, or seeds being scattered into the soil. These seeds can last nearly five years in the soil and can be stirred up at any time. If this happens, you will be right back where you started.

A blue bloom on a group of dayflowers.

Sprays and Weed Killers

One of the most infuriating things gardeners and landscapers alike find about dealing with these weeds is that they are highly resistant to weedkillers and common herbicides. Spray a weed patch that includes Dayflowers, and you will often find the Dayflower bunches continue to thrive while the other weeds around them shrivel and die.

However, the use of sprays is not entirely without hope. Some have found favorable results when using an herbicide which employs a combination of sulfentrazone and cloransulam-methyl. Working in tandem, these two chemicals have some promise in helping curb an overabundance of Dayflowers.

Are There Benefits to Dayflowers?

Two blue dayflowers.

Medicinal Benefits

While the ferocious growth of the Dayflower does make them a common gardening and landscaping nuisance, that does not negate the medicinal benefits of this weed type. Like many weeds, the Dayflower have been used for healing purposes around the world.

Particularly in portions of Asia, the Asiatic Dayflower has a storied past for its medicinal uses. These include treating fevers and throat infections. More recently, worldwide studies have proven that there are several antibacterial compounds in the common Dayflower as well.

Edible Uses

More common even than their medicinal uses are the edible applications for Dayflowers. In various parts of the world, the Dayflower has been noted for their uses in food, which can help somewhat offset the obnoxiousness of their rapid spread.

In fact, in China, Dayflowers can many times be grown on a small scale for commercial purposes and sold as a leafy vegetable crop. Quite the contrast from its typical weed status elsewhere in the world!

Two blue dayflowers on a broadleaf plant.

A few of the common uses for the Dayflower in culinary arts is as a component of salads or a topping on sandwiches. After a thorough washing, they can simply be sprinkled on top as you would sprouts. The gentle flavor of the flowers, young stems, and young leaves has been compared to a pea, while the texture adds a good, leafy kick.

When using these Dayflowers, typically you will want to forage for just the topmost cluster of flowers and their buds, down to the first few leaves. These will prove the most tender and easiest to use and consume in their raw form.

Older Dayflowers, cooked down and tenderized, have also been used in lots of cuisines. These include their application in stir fry dishes, curries, and various soups.

Wrapping Up Dayflowers

Closeup of a blue dayflower blossom showing six stamens.

Feeling prepared to identify and address Dayflowers in your garden and landscape, or while foraging in the wilds?

If you feel like you need to learn more about these pesky garden tenants, check out our weeds page to learn all about different weed varieties, treatment options, and surprising information.