Thanks. That made interesting reading. I certainly have favourites which I have grown for several years and which never let me down. Most of them are well-established varieties which have been around the block a few times.
I hadn't thought of it but, of course, the definition of 'difficult ' in this context is highly specific to the immediate environment of the variety in question. Although it is puzzling that all my common nivalis, planted 17 years ago, are thriving on neglect, wherever they are in the garden! I imagine Steve has more light to shed on this having shown such persistence with numerous varieties.
I have now had some great advice about RM so my immediate concern has faded! Still need to learn which ones to avoid though.
