How big are snowball bushes before they bloom?

I have a small snowball bush/hydrangea that was given to me about 2 summers ago. It was barely 2" tall, because my friend's husband kept mowing it over... I was worried it might have become a "bonzai" plant from it, but it has now grown to about 7" or so tall, and gained a second branch. I have mulched it with oak leaves, as I heard that will make the flowers blue when it does bloom.

How big are snowball bushes before they bloom ? I was just wondering when to expect it to begin blooming.

I definitely have a trellis and a large rock there to protect it from wayward lawn mowers.

 

I have had them bloom between a foot and a foot and a half. They don't like lawnmowers.

Jerry

 

thanks. Maybe it will get that tall next summer? It has been happy since it is no longer getting mowed.