These are called dayflowers. 
Dayflowers are special plants. 
Their flowers do not last long. This is why they have that name. Most of them are blue. Some are yellow or white. 
These plants have leaves that grow in rows. The flowers grow in a special leaf. This leaf can hold a sticky liquid.
In some lands, people eat the leaves. They are used as food. These plants can live for one year. They can also live for many years.
Dayflowers are a group of about 208 plants. People call them dayflowers because their flowers have short lives. 
Most dayflowers have blue petals. Some are white, yellow, or peach. The flowers are zygomorphic. This means they have only one way to be split into equal sides. They grow inside a special part called a spathe. A spathe is a leaf that wraps around the flower stalks. These spathes often hold a sticky, thick liquid.
Some people eat the leaves of these plants. In parts of Africa and Asia, they are a vegetable. One famous type is the Asiatic dayflower. It is a common weed in North America and Europe.
A man named Carl Linnaeus named this group. He named it after two Dutch botanists. He used their names to represent the showy petals. The plants have roots that are often fibrous. This means the roots look like many small threads.
Dayflowers are a large group of plants. There are about 208 different species in this group. They belong to the family called Commelinaceae. People call them dayflowers because their flowers do not last long. Some people also call them widow's tears. These plants can be annuals that live one year. Other types are perennials that live for many years. 
These plants have a very special way of growing flowers. The flowers grow inside a part called a spathe. A spathe is a leaf that wraps around the flower stalks. These spathes often hold a thick, sticky liquid. Inside the spathe, the flowers grow in clusters called cymes. There is often an upper cluster and a lower cluster. The upper one might be very small or have male flowers. The lower cluster always has several flowers. 
A famous scientist named Carl Linnaeus named this group. He was a Swedish taxonomist from the 18th century. He named the genus after two Dutch botanists. Their names were Jan Commelijn and his nephew Caspar. Linnaeus used their names to represent the two large petals. This was a way to honor their work. 
The flowers have a unique shape. They are zygomorphic, which means they have only one plane of symmetry. Most dayflowers have blue petals. You can also find them in white, yellow, or peach. Some are even lilac or apricot. The flowers have three stamens to make seeds. They also have staminodes, which are stamens that cannot make seeds. The fruit is a small capsule that holds the seeds. 
You might see these plants in your own neighborhood. The Asiatic dayflower is very well known. It grows as a common weed in Europe. It is also found throughout eastern North America. In other parts of the world, people use them for food. In Southeast Asia and Africa, some species are eaten as vegetables. 
Commelina is a large genus of flowering plants. It contains approximately 208 different species. These plants belong to the Commelinaceae family. They are often called dayflowers because their flowers have very short lives. Some people also refer to them as widow's tears. These plants can be annuals, which live for one year. They can also be perennials, which live for many years. 
The physical structure of a dayflower is quite complex. Most species are herbs with fibrous roots. Some rare types have tuberous or rhizomatous roots. Their leaves are arranged in different ways. They may be distichous, meaning they are in two rows. They might also be arranged in a spiral. The leaves can have a petiole, which is a small stalk. The way the leaves fold in a bud is called ptyxis. This can be involute, where the edges roll inward. It can also be supervolute.
The way these plants produce flowers is very specific. The flowers grow in clusters called scorpioid cymes. These are also known as cincinni. These clusters are held inside a spathe. A spathe is a modified leaf that wraps around the flower stalks. These spathes often contain a mucilaginous liquid. This is a thick, slippery substance. The spathe might have separate edges. In other cases, the edges may be fused at the bottom. 
Inside the spathe, the flower clusters follow a pattern. There is often a distal cyme and a proximal cyme. The distal cyme is the one further away. It might be vestigial, which means it is very small. It may also hold one to several male flowers. The proximal cyme is always present. This cluster is multi-flowered. These cymes are monochasia. This means they have a single branched main axis. The side branches grow alternately on opposite sides.

The flowers themselves have a unique shape. They are zygomorphic. This means they have only one plane of symmetry. Each flower has three unequal sepals. These sepals might be free or partially fused. The petals are also unequal. Two upper petals are large and clawed. The third lower petal is usually smaller. It often has a different color than the others. Most flowers are blue. However, you can also find lilac, lavender, yellow, peach, apricot, or white flowers. 
Inside the flower, there are parts used for reproduction. Each flower has three stamens. These are the parts that produce pollen. They also have two to three staminodes. Staminodes are infertile stamens that cannot make seeds. The stamens are located in the front. The staminodes are located at the back. The central stamen often looks different from the side stamens. The ovaries can be bi- or trilocular. This means they have two or three internal chambers. Each chamber may hold one or two ovules.

The history of this genus is tied to famous botanists. The Swedish taxonomist Carl Linnaeus named the genus in the 18th century. He named it after two Dutch botanists. Their names were Jan Commelijn and his nephew Caspar. Linnaeus used their names to represent the two large, showy petals. This naming honors their scientific work. Today, many species are well known across the globe. The Asiatic dayflower, or Commelina communis, is very common. It is a frequent weed in Europe and eastern North America. 

Dayflowers also play a role in human food systems. In Southeast Asia and Africa, some species are useful. For example, Commelina benghalensis is eaten as a leaf vegetable. After the flowers fade, the plant produces a fruit. This fruit is a capsule. It is usually bi- or trilocular. In rare cases, it is unilocular. The capsule is bi- or trivalved. The seeds inside are arranged in a single row. This arrangement is called uniseriate. The seeds have a linear hilum and a lateral embryotega.
🖼️ Images & Media (1)
More to explore
✨ What else?
Related topics you might enjoy
What is Nepedia?
A free, ad-free encyclopedia for children. Every article is written at five reading levels, so the same page works for a five-year-old and a fifteen-year-old — use the level switcher above to see this one change. No account needed to read.