Posted: 30/09/2013 at 09:32
I'm confused because you say that you've not pruned them, then you say you cut them down in the spring
Do you water them? Cane fruit like raspberries and blackberries need plenty of water.
Primocane means that they fruit on the current year's growth so, like autumn-fruiting raspberries, they should be cut down to ground level in Jan/Feb. Do that, give them some FB&B and plenty of water and you should have fruit next year.