Introducing 'Natchez', the twelfth release in a series of erect-growing, high-quality, productive, floricane-fruiting blackberry (Rubus L. subgenus Rubus Watson) cultivars developed by the University of Arkansas.According to John R. Clark and James N. Moore of the Department of Horticulture at the University of Arkansas, the new blackberry is a result of a cross of Ark. 2005 and Ark. 1857 made in 1998. The original plant was selected in 2001 from a seedling field at the University of Arkansas Fruit Research Station in Clarksville, and tested as selection Ark. 2241.'Natchez' produces large fruit, near 9 grams on average in research trials. Fruit of 'Natchez' are elongated, somewhat blocky, and very attractive with an exceptional glossy, black finish.