Is it normal for some primocanes of my black raspberries (wild) to die off in extreme heat periods. The leaves turn brown and then the vines. I was hoping that these canes would produce next year. I've been watering every other day or third day during this two week period of high 90s. Too late? I have them heavily mulched and they are clean of weed and the floricanes have been removed. Put a lot of work into them this year. If it is the heat, would black netting suspended (2'-3') above help shield them from the sun?
