We have a productive patch of everbearing red raspberries, here in Madison, Wisconsin. They are located along a fence line, that runs north/south, and they get full sun in the mornings. In the afternoon, they are shaded by the neighbors grape arbor, that is on the other side of the fence, and very dense with foliage. I have seen people growing raspberries in locations that were more shaded than ours, so I know it can be done. However, to get decent growth and fruit production, I suspect that full-sun, half-day is the minimum requirement. Commercial raspberry growers will have the canes growing in rows, with full-sun, all-day.

The more sun the merrier. I have a row where part of it passes right under an apple tree so has almost no sun and it still produces, but just scattered berries. The parts of the row that are in full sun are at least 10X as productive.