You might want to add the Hydrangea forum to the post. Or if it is too late to edit, simply copy the whole post, photos and all, and make the same post over there.

https://www.houzz.com/discussions/hydrangeas

I am not sure if you can do anything to fix this. The tree form removes the lower branches that might support the upper branches. If you do additional pruning, it may send out longer, whipping branches with fewer, larger/heavier blooms, so I don’t think that pruning is likely to improve the situation. Is there something you can use to temporarily support branches if you are home when there is a downpour?

That is one possibility I that I thought of, but was to bring up branches for fear the pressure of doing that would break branches to. Didn’t know there was a Hydrangea forum. Thanks!

I really can’t figure this out on my iPad. Not sure how to do copy paste with this. I will try posting in Hydrangeas and link it to here. I think that will work.

I did that and the link works. Thanks for your help!

I was thinking of something like a triangle of tall welded wire panels that could be folded flat when not in use but set up around the plant when a heavy rain is expected during times the plant is in full bloom. Rather than something to push branches up, it would be something to prevent them getting bent so far down. Once the panicles have dried again after the rain it is less likely to be an issue And the panels could be removed until the next storm.

Alternatively you could selectively nip off blooms where a branch has a particularly heavy load and enjoy the removed panicles as cut flowers.

floral_uk, thanks for the technical help! I tested that out and it worked!