Backyard Orchard Culture: ok to replace one tree

Last year I planted four bare root trees close together (a la backyard orchard culture): Flavor Supreme, Flavor King and Flavor Finale pluots, and a burgundy plum. I somehow neglected to notice that Flavor Supreme needs 700-800 chill hours, which is on the border for what we can expect in Menlo Park, CA, and this year was exceptionally warm. Given global warming, I’m thinking I’d rather not risk having the Flavor Supreme not produce reliably in years to come, so I want to replace just that tree with a Dapple Dandy.

Does anybody here who is practicing Backyard Orchard Culture have any experience with replacing one tree out of a group of four trees in one hole (24" apart), where the trees have been in place just one year? I realize I’ll have to be careful to keep the older trees from overtaking the new tree, but is it possible to make such a change? Any experience shared would be appreciated.

If you have four trees close together the new tree can be badly dominated as trees tend to really take off only in their second year. I would instead consider letting it grow out, and graft it high up with DD or whatever after it fails for you. It would also let you test the chill for yourself.

That said, you can in fact do this by butchering back the other trees repeatedly, but it is a lot of work and will set them all back. I have done this a couple times when I had no choice.