We have DARK or BLACK Cherries
(an excellent dark variety, will require cross-pollination) on Gisela 6. This will ripen very early.
Black York cherry ripens in Early July. Large dark fruit. Would require another variety to pollinate. This would be on Krymsk dwarfing rootstock.
BlackGold, Ripens mid July, large dark cherry. This variety is self-fertile. This is on Kyrmsk dwarfing rootstock.
Montmorency is the most popular sour cherry