Blackberry Plants in the Northern Zone

Prime-Jim and Prime-Jan

• The University of Arkansas introduced these new varieties in 2004. The Prime-Jim and Prime-Jan plants produce fruit on new canes, meaning that even if older canes are nipped by winter temperatures, the plant will produce a fall crop. The fruit is medium-size, with a soft texture and good flavor, according to Iowa State University.

Cherokee

• Cherokee was developed in the Midwest and is hardy to -10 degrees Fahrenheit. This thorny, erect variety produces berries in mid-to-late summer. The berries are medium to large, notes Washington State University, with a sweet flavor and firm texture.

Chester Thornless

• Chester Thornless is an erect, thornless variety developed in Illinois. The plant is hardy to -20 degrees Fahrenheit and produces sweet, medium-sized fruit in late summer to early fall.

Illini Hardy

• Illini Hardy is a thorned variety hardy to -20 degrees Fahrenheit. This erect blackberry produces large, sweet berries in late fall. The berries are excellent for fresh eating, as well as cooking, according to Idaho State University.

Thornfree

• Thornfree is an erect, thornless variety that is cold hardy to -10 degrees Fahrenheit. This bush produces large, sweet blackberries in late fall. The berries were rated "excellent" for fresh eating, cooking and flavor by Idaho State University.

Dirksen

• Dirksen blackberries are hardy to -15 degrees Fahrenheit and are also a thornless, erect variety. Dirksen blackberries produce large berries in late summer to early fall. Idaho State University gave this variety a "good" rating for flavor and fresh eating, and an "excellent" rating for cooking.