Paul you've got me a bit afraid to say anything. But here goes anyway. K5 is the cherry rootstock not K1. K1 is supposed to be for the other stone fruit but really is only compatible with plums/pluots. That has been my experience and the last time I talked to Dave Weil, he admitted as much. Maybe you should call Dave. He holds the patents on these rootstocks.

My plums on K1 and cherries on K5 are planted about 5ft by 7ft. I think they could go even closer on my weak soil. But I really don't have enough experience to be sure about spacing. Your mileage will vary.

The Fruitnut

Thanks for the info Fruitnut. I had a brain fart about the number designations for the Krymsk rootstocks. Sorry if I came off a bit rude in my post. I guess I let my bad mood yesterday carry over into my post. My son decided to enter the "terrible two" stage at 15 months. He's been WILD lately...
I wish I had known about the compatibility issues with Krymsk 1 before I bought so many of them. The people I spoke with from Raintree Nursery told me that Krymsk 1 was compatible with all peaches and nectarines and most plums and apricots. I definitely don't need as many as I ordered now. I guess I'll just go with good old Lovell rootstock.
I was hoping to grow some peaches and nectarines on a dwarfing rootstock for ease of maintenance and the ability to pick all the fruit from the ground.

Does anybody have any Krymsk 1 or 5 they can part with, I got a bunch of unexpected scions I want to grow and can't find that rootstock anymore...

Did you write to Cummins Nursery to see if they have Krymsk 1 left?

Citation will supposedly dwarf peaches/nectarines to anywhere from 8-14 feet. Sounds like what you may be after in that dept. Krymsk 5 will give you a large tree. If you're looking for height control with cherries, I would look for a more dwarfing rootstock. I've heard of a dwarf Stella cherry. Perhaps you could graft other varieties onto it and cut back the Stella as the other varieties take. There is also gisela 5, but you will have to prune it quite a bit initially to keep it from overproducing. There are alternatives out there if you are willing to play around with it. Have fun exploring the possibilities. I just grafted Van and Utah Giant onto my Craigs Crimson on GM 61/1. If they aren't as good I'll whack them and graft the Craigs back in.