Do sunflowers track the sun?

When I was young I heard amazing stories of how sunflowers (Helianthus annuus) turn their flowers throughout the day to follow the sun. The story says that they face east in the morning, track the sun as it moves during the day, face west in the afternoon, and then overnight turn back facing east ready for the sunrise the following day. What an amazing story. I wanted to see this for myself.

When I was a kid I got some sunflower seeds, planted them, tended the plants, and remember being disappointed to see that the flower buds didn’t turn to track the sun at all. I figured maybe they only changed direction once they were open, so I waited. When the flowers opened I was even more disappointed to see that the flowers did not move at all. They stayed facing the same direction that they were facing back when they were fat little buds.

Last year I was talking to someone who told me how I must have misremembered, and that all sunflowers do follow the sun – that is why they call them sunflowers. They said there are even time-lapse videos on the internet of this happening with entire fields. My experience growing sunflowers was a lot of years ago, so the chances of me remembering incorrectly is really high. I grew a variety called Giant Russian and another old heirloom variety intended for poultry feed, perhaps they are too large and heavy to turn a noticeable amount?

This year my daughter grew some sunflowers, they were smaller varieties. If any type is going to turn it is going to be these little ones. So I decided to take notice of which way they faced and get some photos at different times of the day to help me remember correctly.

Somehow I forgot to take photos, which was irritating. Luckily one late sown seed grew, I forgot to take pictures of the unopened flower bud, but I did remember to take pictures of it throughout a day once the flower had opened.

The first picture is of the sunflower in the morning after the sun had been up for a while. Note which way it is facing. I tried to stand in a similar place to take the next two photos, but I may have been off a little. Even being off a tiny bit you will still be able to see how far the flowers turn or don’t turn.

Sunflower in the morning

The second photo was taken at mid-day, note which way the flower is facing here. Again I tried to stand in a similar position, but was off a little bit.

Sunflower middle of the day

The third photo was taken in the late afternoon before the sun went down, again note which way the flower is facing.

Sunflower in the afternoon

As you can see from the three pictures above, the open sunflower does not turn to track the sun. None of the other sunflowers that I forgot to photograph turned, nor did the unopened flower buds. When the plant was very small the growing point did display a bit of heliotropism and tracked the sun somewhat, but once the bud started to develop and become plump its sun tracking stopped completely.

I tried to track down some of the time lapse videos of this allegedly occurring. Not surprisingly all I could find were some poorly faked videos with digitally added rainbows in the background, and nothing that looked even remotely real. How disappointing. Oh well, at least now I know for sure that sunflowers don't track the sun each day.