All sour cherries are sour and don't taste sweet, the sugar level goes up if you let them hang on long, many weeks after ripe, the best one you can grow is which grows best in your climate, you want a tree form or shrub form and we need your zone to help. Sure..some are slightly higher in sugar but very minimal, every one taste better if let on tree many weeks after ripe...if you can?

But I have eaten some sour cherries that are sweet! So basically they are all sweet as long as you let them ripen?

Balaton sour cherry is the sweetest sour cherry I have ever eaten. A friend of mine planted some commercially. They are my daughters favorite as we would eat them right off the tree! Sadly he no longer has them as they were not fully winter hardy for him and suffered from too much winter injury in zone 4.

Stark Nursery in Missouri offered them a few years ago for home growers. I bought one but lost it to deer that browsed it to death. They have an almost dark purple color to the fruit when fully ripe. While Balaton was tasty for fresh eating, I actually preferred a more tart variety for making cherry jam. Balaton was ok for making jam but I thought the jam made from my North Star cherries was far better. Just my preference I guess.

Yea...Balaton ..hard to grow them here, I grafted last year but nothing took..think scion wood was dead frozen when I putted on. If you ate sweet sour cherries then next person beside you might say they're sour..that's how different taste buds are. I know a Dutch man here ..he loves his Evans sour so much that he wouldn't touch a sweet cherry with a long stick lol. I was given a so called sweet cherry tree from the grower but when it produced it was sour cherry Evans! I was given a "better" sour cherry graft from the person saying it's better then Evans cherry, I grafted into my Evans cherry tree, last year it produced and side by side there is no different lol.

Last year I left Evans on the trees another 6 weeks after ripening and brix level went up about another 3 brix...around 14 brix. Allot better eating from the tree then. See below..

Evans