fruit border help/advice needed
I've got a border area which is 9m long and 1.2m wide. It runs along a 1.8m tall fence which is north facing, but also has the tops of my neighbours shrubs, making it around 2.2m tall. Interestingly, there used to be some very old shrubs in the border that grew quite tall and leafy before I removed them. This may be because the tops of the shrubs got sunlight for a reasonable part of the day, or possibly the rich and moist soil underneath them. I would say the soil is quite fertile and moisture retentive/slightly water logged (due to lack of light, warmth or the high water table in the area.)
My predicament is this: I would like to try and grow some fruit in this border. It will be an experiment, so within reason, I am willing to be disappointed! Obviously I would like to do all that I can to minimise failure (choice of fruit, variety, rootstock, training) , but realise the odds may be stacked against me.
I'm interested in desert varieties of apple, pear and plum, and being ambitious (if a little greedy) would like to get as much viable fruit as possible, as tree numbers, rootstocks, planting distance, forms allow.
The actual fence is not in great condition either, and due to it's north-facing orientation would not allow any training onto it. Something like a free-standing espalier shape, with some support rigged up around it might work, but I doubt it. My idea would be to grow trees that would be like half/standards, but no more than 4m tall ie. more at the top, above the fence, where the sunlight is. A concern over apples is they fruit on lateral shoots, so would need to be pruned/trained to encourage these, while being high up in the canopy. Maybe fruit trees that have a naturally upright shape might help. Similarly, would ideas like planting more trees close to each other and severe pruning and summer pruning encourage fruiting? despite the not ideal conditions.
Any ideas or suggestions will be welcome (apologies for the poor diagram.)