The 'Marion' cultivar (Rubus L. subgenus Rubus) or Marion blackberry, is a hybrid caneberry developed by the USDA ARS breeding program in cooperation with Oregon State University. It is a cross between the 'Chehalem' and 'Olallie' berries. The marionberry is currently the most common blackberry cultivar, accounting for over half of all blackberries produced in Oregon.
The powerful flavor of the marionberry has led to it dominating current blackberry production. It is often used as an ingredient in pies, ice cream, jellies, jams and other foods, over other blackberries.
The marionberry is a vigorously growing trailing vine, usually producing just a few canes up to 20 feet long. The vines have many large spines, and the fruiting laterals are long and strong, producing many berries. The berry itself is glossy and, as with many blackberries, appears black on the plant but turns a deep, dark purple when frozen and thawed. It is medium in size and tends to be conical, longer than it is wide. The berry has a somewhat tart flavor, fairly earthy with traces of sweetness. It is larger, sweeter and juicier than the 'Evergreen' blackberry. The relative complexity of its flavor has led to a marketing label as the “Cabernet of Blackberries”.