I am getting bare root Korean Giant and Shinko pear trees in the fall. Wondering if I can plant them close together in a 5 foot radius hole, probably 3 ft apart. These two pollinate each other and I don’t have room for separate planting. Will this be a bad idea?
Many people have them close. You will just have to prune more to make it work.
There is a French version of planting them that you can put up to three trees in basically the same hole. Put them about 18" apart, tilting them slightly outward. That way you can prune them to keep the sun to get to the trees and become less tangled in the interior. Trees of Antiquity site talks about this method.
I think I’d much prefer a multi-grafted tree to two pear trees growing together. And if you haven’t done any grafting before I can’t think of a better species to start with than pears. Pears are very simple to graft. I like KG better than Shinko, but I might keep the Shinko and graft the KG into it rather than the other way around, because the Shinko has better form. But, on the other hand, KG has had less serious trouble with fireblight in my experience than Shinko, so maybe that would be a reason to use KG for the main frame.