I like your fruit forest idea. Except for the house and vegetable gardens, my whole lot is a fruit and nut orchard.
I started with dwarf fruit trees. I don’t think any of them lived more than 8-9 years. They just aren’t as hardy as larger trees. In a drought, their
roots aren’t as deep and they can’t reach
water. They don’t stand up to wind as well. They don’t seem to fight diseases as well.
When I am selecting grafted trees, I always want to know what the rootstock is so that I can match it to my conditions.
You said fruit “forest”. Is there any reason it needs to be just in that square? I would at least scatter a few trees around the rest of the yard and round off the corner of the square. You might plant in curves or randomly if you don’t want it to look like an orchard.
Apple and peach are high maintenance trees, especially if you don’t use chemicals.. Selecting for disease resistance helps. You might consider some trees that need less care like persimmon and mulberry. I would plant grafted varieties though since you don’t have a lot of room to plant seedlings that may turn out to be male only or not produce for some other reason.Montmorency Cherry is almost carefree here in western Missouri. It usually misses the frosts and hardly ever have insect or disease problems. Pecans and walnuts are low maintenance, but I’m not sure if you have room.
Thornless blackberries probably require the least care of any fruit. You could also plant raspberries and strawberries between your trees.
Raintree Nursery has the best information I’ve see about rootstocks and a huge number of tree varieties. It is a very good company.
Edible Landscaping Nursery has the best plant descriptions and care information that I’ve found. It is my preferred company. I like all the information and that they
sell potted trees. I’d rather have a smaller potted tree than a slightly bigger bare
root tree.