On 30/09/2017 20:16, Judith in England wrote:

I have grown some sunflowers either side of a patio door - facing south.

I was really quite cheesed off that instead of facing south and be visible -
the flower heads decided that they were going to face north : ie toward the
wall.

I then realised that when sunflower heads follow the sun: they don't actually
have "eyes" - they are following the source of the heat.

I think that my sunflower had realised that rather than waste energy following
the sun: it was much better to face the wall all day, and every day: and get
the heat from the brick wall !!


It appears random as one of our four tall ones, standing in the open,
insisted on facing northish
while the rest more or less faced southish. At least they're still in bloom.