Hydrangea serrata 'Blue Billow'

Rkw
It looks good, never new there were so many different varieties until recent years when they became more popular in the UK.

I am just curious why this sort of Hydrangea has always just few flowers.

It had quite a few flowers earlier this summer, many of them are now hidden in foliage or have been cut off. I cut this back after flowering so it keeps a better shape. Many of the newer varieties flower on old and new growth, this is an older one that flowers only on old growth. The flowers are very small compared to some lacecaps but still very pretty.

Sure. These are decorative by their leaves, too. Your is already showing its autumn colours.

Hydrangeas are hard to find in this part of the US, winters are cold enough where most hydrangeas will do well only if they are planted in protected areas. Even then after a hard winter they might not flower and will have dieback. I have to go to specialty nurseries or mail order to get anything other than Endless Summer. They might not do great every year but the years that they do makes up for it.