Blackberry is used as a generic term to refer to a wide range of bush berries ( loganberries, boysenberries, marionberries and ollalieberries), the fruit is a member of the Rosaceae family and of the Rubus genus. They are sweet, slightly tart and juicy. Blackberries are a good source of vitamin A, vitamin C, iron and calcium. Blackberries can be added to both sweet and savory dishes.