Boysenberry is a hybrid developed by crossing the raspberry, blackberry and loganberry. It was developed in the 1920's by Rudolph Boysen. Similar in appearance to a large raspberry, the boysenberry has a rich purple-red color and pleasantly tart flavor. They can be used like raspberries and blackberries and are especially good in cobblers, ice cream, pies and preserves. Highly perishable, they are seldom seen in supermarkets, so look for them at farmers' markets. Boysenberries should be stored in a single layer in the refrigerator and used within a day or two.