This is a big leaf/macrophylla hydrangea. If you’re fortunate enough to have them bloom(🤣😭!), you may have a different problem, which is that they sometimes outgrow their space. You can move and divide these if needed. When? You can do this any time the ground’s not frozen, including when they’re in bloom if necessary. It’s important not to prune these otherwise no because you could be cutting off the buds that will turn into flowers. (Is your not blooming at all? Just get an oakleaf hydrangea