High chilling/low chilling. Most of the blackberries and raspberries we grow in NC need to accumulate a high number of chilling hours in order to break bud and grow 'normally' next summer. Contrary to what you may initially think, we don't want low chilling plants. We want high chilling plants that can stay dormant when we get January thaws. However, this year it does not look like we are making progress to that high chilling number. We will be keeping track of it over the next few weeks.
If you live in the SEUS, you can find probably find out the chilling hours in your area. The NC State Climate office has a great tool you can use if you want to calculate the chilling hours in your area. Here is a link. http://www.nc-climate.ncsu.edu/cronos/blackberry/