Hi, if it's been flowering for a while, it's probably making seed, and the weight of the seed is making it droop, can't think of anything else, if you want the seed for next year leave it until the seed ripens, if not just cut it down, Derek.

It's normal - they all do that.

Soon you will see finches hanging upside down getting seed from the flowerhead. Sunflowers keep their heads up for the bees and bend their heads down for the birds.

Even the cardinals & sparrows get in on the action. Soon the heads will face up again - when all the seeds are gone.

I left ours to ripen and finally cut the heads off and kept them - then put them out for the birds in the winter.

I leave them to ripen and let the birds have a feast.

I had a squirrel haul off with the entire plant he cut down himself.