You may have observed that older and more mature sunflowers tend to stay facing the east, and there’s good reason for that. Happier and more healthy flowers get their nutrients from the sun, and as the sun rises in the east – they’re getting more from the morning sun.
A new study has stated that you would more likely find that the more mature and cheerful-looking blooms of sunflowers are facing towards the east, despite younger sunflowers orienting towards the sun throughout the day. Older sunflowers don’t have the flexibility of younger sunflowers, so why do they aim to face the morning sun when presumably the sunset would be the sun they see last.
Well, to answer that question you have to understand that there is a difference between the morning sun and the evening sun, and you’ll find that the morning sun has a greater warmth. Due to the greater warmth, the sunflower can also benefit from a range of natural factors that come with it. For example. The warmth of the morning sun can also attract more bees – which in turn will encourage better growth and pollen production. Not only that, but the production of seeds and reproduction is much more likely to succeed.
If you’ve seen a large field of sunflowers, you might have noted that it’s strange that they all face the same way – especially within the older and maturer plants. And now you know that it’s because they aim to face the sun during the time that they gain the most benefit from it. As when they mature, they lose the flexibility and ability to follow the sun throughout the day – east is the direction that is best for them.
So why do sunflowers lose their flexibility as they mature? This is due to as they grow, their stem hardening and becomes stiffer – else they would not be as structurally stable. As they start to become stiffer, they gradually start to stay east-facing.
Before this discovery was made, researchers could not figure out why it was that sunflowers settled in an east-facing direction. It’s not always easy to observe such a thing without knowing what could be affected if things were different. And so studies were carried out to find out what would happen if sunflowers were settled in a west-facing position. The research turned up that the sunflowers that were not facing east were attracting fewer bees, and thus the sunflower would have a much lower chance of reproductive success. Of course, all they had to do to begin this study was to turn sunflowers to face the west – away from the rising sun and towards the evening sunset.
The study did not show that the bees showed less overall interest toward the sunflowers that were west-facing, however, it showed that bees were more drawn to the sunflowers that were facing east during the morning. After the morning had ended, it was noted that the bees showed no preference towards which sunflower they were attracted to. This is what suggested that the morning sun provided different results for both sunflowers and bees than it would for the rest of the day.
It was also noted that the east-facing sunflowers had started to produce or release their pollen a little bit earlier in the morning than those facing west – which is clearly a result of having the rising sun’s warmth. Of course, the sunflowers that release their pollen earlier are also going to attract bees to them earlier also. It has been suggested that the release of the pollen is due to the temperature of the capitulum.
Not only did the east-facing sunflowers have a higher reproductive chance, but they also had quite a notable difference in the seeds that they produced. East-facing sunflowers produced more and heavier seeds than that of the west-facing sunflowers, which were lacking the warmth of the morning sun. Despite both sunflowers getting a full day’s worth of sun, when facing towards the morning sun, the flowers seemed to get a much more positive gain.
To test the reproductive success of west and east-facing sunflowers, a test was done on flowers facing both west and east, and the offspring of the sunflowers were tested to find out whether or not they had come from east-facing or west-facing sunflowers. It had turned out that the east-facing sunflowers had a significantly higher success rate than that of the sunflowers that were facing the west.