No, not normally. Annabelle has weak stems and it suffers from this problem when it has big blooms and it rains enough that the added weight makes them tumble. But ES should have stronger stems. Most likely it was the pooches.

I just had another plant flattened like yours 2/3 days ago too. The plant, not a hydrangea, was besides an iron structure that I use for climbing vines. I speculate that my dogs saw some vermin that ran/jumped into the structure and they stomped on top of the plant trying to get "it". Sigh... these baby girls of mine....

Thanks that makes me feel better about the plant. I was already trying to figure how to cage it up without it looking stupid for next year. I guess I,ll just have to figure out how to keep the animals out of it instead.