Help!! Last year I bought two sweet cherry fruit tree varieties, Ulster and Emperor Francis. The lady who sold them to me insisted they were pollinators for each other. Have lots of sour cherries this year (I know, they self-pollinate), but not a single sweet cherry. Did some research this year only to find these two varieties do NOT pollinate each other. I have since bought a Black Tartarian, which I was told was a great pollinator for other sweet varieties, but after spending what seems like hours online, it only suggests Bing or Stella or "other sweet varieties" to pollinate the Tartarian. Would love if someone with some sweet cherry experience can please tell me if these three will work together and cross pollinate or if I need to seek out yet another variety to get sweet cherries next year! Maybe I should have stuck with apples!! :) Thanks in advance for any advice you may have!!!