pd wrote:If you want to prune it just remove old and weak growths leaving young vigorous shoots. Do this in May or June.
As for winter I don't see that you need to do anything apart from having it well tied back or otherwise supported so heavy snow does not damage the stems. Here in the UK they are perfectly hardy.
Kerria flowers on the previous years wood so you will not see all stems bearing flowers.
I wasn't sure about the tieing back of the branches., I will try it this year.
Do you think i should tie them together and stake them up? or should i try a bring them closer to the ground? Darn garden books never tell you what to do in the winter.