DanDanDan: I'm not an expert either, but firstly are they the fruiting cheery type not flowering cherries. I haven't had to prune mine but it's only 2 years old. Last year we only got a dozen or so cherries but it's laden this year. Also could be the variety might need a pollinator, Hope this helps.
(sakla) If you only look at some of the discussion boards on a regular basis you can add them to your favourite boards list by going to the Board page and clicking "Add to my favourite boards". (pauloaguia) (Bütün ipuçlarını göster)