I have 3 fruit trees in pots that are now 3 yrears old. This spring only the plum is showing any signs of life. The cherry and the fig look dead but how do I check? I did notice that both looked 'unhappy' at the end of summer and all the fruit fell of before maturing (can't really blame then - it was awful) I am happy to leave them alone and see what happens if that is the best. They are all in the same place in the garden so that is not a factor.
Hi Jan My Greengage looked unhappy last year the leaves and branches started browning very quickly and the fruit on it rotted very quickly around about the same time as yours. See my blog on this section named Greengage tree dated 22/4/13. I have 6 other fruit trees (7 altogether) and had an abundance of fruit from all of them. I think you need to do the scratch test on the branch and if it is still green underneath there is still life.
Besides the scratch test, you might be able to lift one out of the pot to check the health of the roots. Vine weevil grubs attack many ornamental fruit trees in pots, and you don't know they have been there until it's too late - your description indicates some distress last summer. ) . If it was vine weevil, there may not be any grubs left by now, but the root system will have been attacked and it should be noticeable.