I planted raspberries, 6 yrs ago, and although they come up every year, they only get about 2-2 1/2 ft tall and have never bloomed or produced fruit. Our soil is alkaline. I have tried using gypsum and nitrogen in the soil. Any suggestions?
This article will help with acidifying the soil:
In addition, you may want to ad some phosphorus to help with blooming and fruiting. The best way to tell what your soil needs, however, is to have it tested.