Grow Your Own Magazine

About 3 or 4 years ago I purchased 4 apples trees and a plum tree, and since then I've pretty much left them to just grow how they like.

They all started out ok, but 2 of the apple trees didn't produce apples last year and the plum tree hasn't produced plums for the last 2 years and I have no idea why.

The plum tree is supposed to be self polinating (and was ok for the 1st year) and the apple trees were all picked from groups that are supposed to polinate each other - so what's the problem?

Do I need to prune them? Are they putting their effort into growing rather than producing fruit? If they need to be pruned, how (where) do I prune them, and when?

Have they been fed and watered?
Pruning is usually done at the end of the season.

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If it ain't broke, don't fix it and if you ain't going to eat it, don't kill it