What is the best time of year to transplant rhubarb?

Black raspberries should be topped during the summer month when they attain 36-inches in height. Trim back 3 to 4-inches of new growth. This encourages the development of lateral branches and increases the strength of the cane. During dormancy, remove all dead, damaged, and weak canes. Lateral branches should be trimmed back to 4 to 7-inches.