Today in Savannah GA at the Vegetable and Fruit Conference, Wayne Mitchem, Ervin Lineberger and David Lockwood held a session on Winter Injury in blackberries. Here are Waynes Slides. He is a grower in the Lincolnton, NC area. Wayne Mitchem outlines the scenario on his farm during the 2013 growing season and the winter of 2014 below.
In short, the conditions that were present on his farm during the 2013 season, lots of rain and late harvest season of Navaho kept the plants from hardening off. The result was cane injury to his Navaho plants most likely occurred in November.
He lists some great management suggestions in the last slide and made during the session:
-prune out dead canes, this will minimize diseases that may be harbored in the dead canes, and increase air circulation in the canopy
-foliar fertilization may help in spring and summer to help deliver nutrients to the developing crop. (see comments on previous blog post http://teamrubus.blogspot.com/2014/04/cane-damage-what-to-do.html)
-there will be a need to increase pruning in 2015, as more canes were produced in 2014
-damage in November made plants more susceptible to cold later in January
See other posts on winter injury here: