For fruit trees, the yields would be best with a vigorous rootstock and a full time size tree.
However, these trees would not translate well to the trained forms. Dwarf or semi-
dwarf would be more appropriate here and the governing factor would be how many
branches could be supported.
Gene Yale is a member of our Midfex club and he has squeezed close to a hundred varieties
of apple trees into his small urban lot, but none of them has espalier form. I hope you are aware
that espalier requires a lot of work to set up and maintain.

Sherwin D.

honeyman wrote:

I have taken on a plot of land 12meters square and intend planting it
as a small fruit orchard, with apples, pears, plums, cherries and
gooseberries as a surrounding hedging (keeps the 2 legged rats at bay
;-). What trained forms, cordons, espalliers, or bushes should yield
the heaviest harvests from this site?