Thank you for your kind replies and additional images.
Astilbe comes in a variety of colours and sizes.
There is a lot of information here:
http://youngamericangrowers.com/astilbe-history
: George Arends, a noted botanist and nurseryman from Ronsdorf, Germany, is responsible for introducing the majority of the Astilbe cultivars, many of which bear his name. Most of the species and varieties Arends bred were from Asia - China, Korea and Japan. Interestingly, Arends seemed to have passed over the only American representative, A. biternata.