Ok, so there is not enough crop for even a gallon of cider. Well last year that happened to lots of small scale growers and one or two reported that a late glut of blackberrys meant that rather than eat their few apples, they added them to the berries to make an apple and blackberry wine. This is a british hedgerow classic combination. We all know they taste great together in pies and sure enough they taste amazing together as a wine too.
However you will need a decent wine yeast rather than a cider yeast to produce a good finished drink.