Plums show great diversity of color, form, size, taste and use. European plums are the blue plums, including prunes, with firm flesh, that mature late in the summer. Most will freely interpollinize. Japanese plums bloom earlier, mature earlier and are juicier in the flesh. Damsons are small, usually blue, and used principally for jams and jellies. Plums are adaptable to more climates and soils than the other stone fruits.