My nankings are about 2-3 feet apart and they are quickly growing together (3rd year in the ground).

My nankings and hansens bloomed about 1-2 weeks apart. The nankings bloomed first followed by the hansen's a week or so after the nankings had finished. But we did have a snowstorm during that week, so it may have shortened the bloom time for the nankings.

I've read that they can pollenate eachother, but as this is the first year my hansen's have bloomed and there was that snowstorm, I cannot say for sure what happens most years, just what happened this year.

~Chills