Earth

Sunflowers are pretty and helpful: Lifeform of the week


Image via Susanne Jutzeler/ Pexels.

Sunflowers aren’t just pretty, but they have many helpful uses. People plant sunflowers in places where there have been nuclear accidents to help the soil recover. Plus, all parts of the sunflower are beneficial. They can serve as both food and fuel. Sunflowers have a circadian rhythm that help them follow the sun. And if you think all sunflowers are yellow … Surprise! There are many different types and colors.

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Meet the sunflower

There are about 70 species of sunflowers. Most of these species are robust plants, composed of leaves and stems with a rough texture. The leaves are located in alternate positions along the stem and have serrated edges.

The stems are straight and firm without branches, which allows them to reach a size that can exceed 10 feet (3 meters) in height. The tallest sunflower was from Germany and stood at an incredible height of 30 feet (9.2 meters).

And what about the head? If the sunflower is big, the head is too. Their dimensions can vary from 2 inches to more than 15 inches in diameter (5 cm to 40 cm). The center consists of hundreds of tiny tubular flowers, from which the pips (seeds) emerge. Large petals lie in groups of two rows around the head.

A sunflower on a long stem with big leaves, brown center surrounded by brilliant yellow petals.
Sunflowers have straight and firm stems. The heads have petals in 2 rows and the seeds are in the center. Image via Jirasin Yossri/ Unsplash.

Are all sunflowers yellow?

In general, sunflowers have yellow petals and brown centers, but those aren’t the only colors they can have. There are sunflowers with orange, red, purple, pink and even white petals. Additionally, the center can be lighter or darker. Velvet Queen, Chianti and White Nite sunflowers are striking.

Flower with long, oval red velvet petals and a big dark center.
Not all sunflowers are yellow. This is a Chianti sunflower. Look at that red velvet color! Image via Rob Duval/ Wikipedia (CC BY-SA 3.0).

And, as if that were not enough, there are also varieties of sunflower that do not have the shape we’re familiar with. Look at this sunflower called Teddy Bear, a fluffy cultivar (variety within the same species). It gets its name from its pompom shape, which has a fluffy and soft texture.

Donut-shaped big fluffy ring of yellow-orange tiny petals against big green leaves.
The Teddy Bear cultivar (variety) is totally different from what we are used to seeing. Image via Mike Peel/ Wikipedia (CC BY-SA 4.0).

Do sunflowers always follow the sun?

This is a heliotropic plant, meaning it can move its head and follow the sunlight from dawn to dusk. However, only the youngest flowers perform this movement. Once they reach maturity, they stare fixedly to the east. This position allows for quick warm-up in the morning and, as a result, increases visits from pollinators.

The young plants reorient themselves toward the east during the night in anticipation of the morning. The most curious thing is that they follow a circadian rhythm, synchronized by the sun, which continues if it’s cloudy or if the plants are moved to constant light. Also, young plants can regulate their circadian rhythm in response to artificial light, although resynchronization takes time.

A big flower on a thick, hairy stem pointing at the setting sun so that only the flower's back is visible.
Young sunflowers follow the path of the sun. But mature sunflowers stay fixed looking at the east. Image via Aaron Burden/ Unsplash.

What do sunflowers have to do with nuclear disasters?

Sunflowers have a life cycle of about three or four months, from the moment they germinate until farmers harvest them. They bloom in late spring or early summer. That’s why you see these flowers in abundance during the warmest months.

When sunflowers receive the necessary hours of sun per day – between six and eight hours – they grow strong and fast. And although sunflowers do not like sudden changes or frost, they are fairly resistant and can tolerate temperate and even slightly cold temperatures well. They also withstand drought and soils of varying acidity.

Plus, it’s amazing what their roots are capable of … They can eliminate heavy metals found in the soil, such as lead, arsenic and uranium. This is why people planted them near Chernobyl in 1986 and Fukushima in 2011 after the nuclear disasters.

Likewise, being a deep-rooted plant, they help break soil compaction and improve its structure. In addition, the sunflower is highly efficient at extracting nutrients, which reduces soil depletion and favors the cultivation of other plants in the following season.

Hillside field with thousands of sunflowers facing the camera. A few trees in the background.
When sunflowers receive around 6 or 8 hours of light, they grow strong and fast. Also, their roots are strong and help break soil compaction, favoring the cultivation of other plants in the following season. Image via Stefano Zocca/ Unsplash.

Uses of sunflowers

If helping us get back to normal after a nuclear accident doesn’t seem enough to you, know that our dear friends have many more uses.

Sunflowers’ main use is as food. Their seeds, or pips, are edible. They are covered by a dark layer with cream-colored lines that protect the seed. When temperatures are high, they dry out for harvesting.

You can simply peel and eat them, although usually they’re dried further or baked within their shells. They can also be toasted and salted, making for a delicious snack. Chefs also use the peeled seeds in breads, salads and many more dishes.

Another use for the sunflower seed is in making sunflower oil, which is rich in vitamin E. And sunflower oil has many uses, from cooking to soaps and cosmetics to biodiesel.

Likewise, the petals are useful in making wines or infusions. The stems contain a fiber used in making paper. And the rest of the plant is often used as animal feed.

Closeup of a sunflower with bees on green and brown center and brilliant yellow petals around it.
We can benefit from all parts of this plant. We can eat the seeds as a snack, use them in salads, produce oil, biodiesel, cosmetics … and creatures such as pollinators and birds love them too! Image via Caio/ Pexels.

Where does this wonderful plant come from?

The sunflower is native to Central America. It is an old plant, already cultivated in the year 1000 BCE. In many cultures originating from the Americas, such as the indigenous people of Mexico (Aztecs and Otomi) and Peru (Incas, Chanka, Huanca and Chachapoyas), the sunflower was a representation of the solar deity. This plant represented prosperity and wealth. And they were right, because we’ve already seen the good these plants can do.

It was the Spaniards who brought sunflower seeds to Europe in the 16th century, and from there, they began to spread throughout the world. Since then, people have found many uses for them. Not to mention the number of artists who have used sunflowers as a source of inspiration. Have you seen the work of Vincent van Gogh or Claude Monet?

Maybe now that you know all these things about sunflowers you would like to plant them in your garden. You will also see them in a different way when you see entire fields of this showy, joyful and full-of-life plant.

Immense field covered with brown-centered yellow sunflowers, under a partly cloudy sky.
Sunflowers not only serve as food or fuel, but they also eliminate heavy metals found in the soil, such as lead, arsenic and uranium. They were planted after nuclear disasters to help the land recover. These plants are full of life. Image via Jeb Buchman/ Unsplash.

Bottom line: Sunflowers are amazing. You can benefit from all their parts. They offer us food, oil and biodiesel and they even help the land recover after nuclear disasters.

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Posted 
November 11, 2024
 in 
Earth

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