Sunflower Sun Calculator: How Much Sun Does Sunflower Need

Sunflowers need a lot of direct sunshine to grow well. Full Sun means at least six to eight hours of direct light each day. If you get the most or even more, that helps best.

These plants want long and warm summers to flower well. To have the strongest stems and the nicest flowers ground them in full Sun is key.

Sunflowers Need Sunlight and Turn Toward the Sun

Sunflowers do well in warm climates with a lot of sunshine. They are known for their skill to last in dry conditions, which makes them a liked crop in many regions. They also need well drained ground.

It is important to choose a place to plant with rich soil and enough daily light. Seeds go in the ground one to two inches deep. Protection against strong winds helps, because the plants then grow taller.

Planting beside a fence or building can stop the wind and prevent the stems from becoming too slim.

Direct sunshine simply is open access to the rays of the Sun, when the plant gets full and strong light during most of the day. Sunflowers use that light to fuel there growth and reach their top height. They are truly Sun powered.

Their flowers come directly from how they interact with the sunshine.

Young Sunflowers truly follow the Sun across the sky. That move is called heliotropism. Scientists thought that this tracking works like phototropism, which is the way most plants turn toward light.

Phototropism is controlled by a molecule called phototropin, that reacts to blue light. But the tracking of Sunflower showed itself to have another cause.

Sunflowers have hormones called auxins. Those hormones for growth sense the sunshine. They move from the sunny parts of the plant to the shady parts of the stem.

There, they push the cells to grow and stretch. During the day the east side of the stem stretches, and overnight the west side. Those back and forth moves help the top of the plant twist from east to west.

The steady tracking helps young Sunflowers become bigger. Heliotropism gives them ten to fifteen percent more sunshine than if they would stay still.

Only young Sunflowers do this tracking though. When they mature and their stems become thicker, the movement slows and finally stops. After maturity, the flowery heads set themselves facing east.

Facing east is truly useful, because the morning sunshine warms the plant up more quickly. That heat helps to attract bees andother insects.

The face of Sunflower is surrounded by bracts, which are green sheets forming a crown. When the plant is young, those sheets cover the whole face and work as a big leaf solar panel that gathers sunshine. Seeds of Sunflowers do not need light to start to sprout.

But after they burst, you should lay them in bright light so that they keep growing. When it comes time to harvest, you should hang the dried flowery heads upside down in a warm place with good air flow and protect them against direct sunshine.