There is a veryactive 'perenial plant society' in CH, both on German and French-speaking part, with a magazine and many events (including guided visits, plant swap fairs, seed exchanges, lectures, etc)- but they do not have a Forum.
www.amisdesvivaces.ch/
in French and German.
I am also very happy to do perenial plant exchanges any time- and add to my collection. I live in an old Vicarage in the mountains- and I am very mcuh of fan of 'Curate's gardens' and Gertrude Jekyll- the queen of English country gardens.