Belle de Louvain - An excellent hardy choice that is suitable for growing everywhere and normally produces good crops, the potential is for very heavy yields. Belle de Louvain is predominantly a cooking variety. Belle de Louvain plum tree – season Usually ready mid August and may be used into September; hangs on the tree well. Belle de Louvain Plum – appearance & flavour Medium sized oval, reddish becoming deep purple with a slight dusky bloom. Very tart flavour that becomes rich and decadent when cooked, superb for bottling, jams, pies and freezing. Belle de Louvain Plum – pollination Belle de Louvain Plum trees for sale An excellent hardy choice that is suitable for growing everywhere and normally produces good crops, the potential is for very heavy yields. Belle de Louvain is predominantly a cooking variety.