Carol
I’ve found that fruit trees do really well if you use spent tomato/potato pot compost the following spring. OK, my tomato/.potato compost gets feeding with tomorite and/or comfrey tea during the summer months, but it worked really well on pear, plum and cherry (all on root stock to limit height to about 6ft) in 2015.
I also used it on a specialist salad bed and the lettuce and rocket grown there through the season did well too.