Wait until you harvest all berries from your bushes before cutting back the plant in the fall or winter.
Look over the plant to note two kinds of canes sticking up from the ground: first year canes that are green in color and tender, and second year or older canes that appear reddish brown and woody. Very old canes are brownish-gray and brittle.
Trace each of the older canes down to ground level where they emerge from the soil. Use hand pruners to clip horizontally across the base of the old canes one at a time, and then pull them from the bush area.
Clip off the old canes until all that remains of the raspberry bush are the new, green canes that are in their first year of growth. Discard or safely burn the removed canes.
Tie plant ties around the base of the remaining canes, if desired, to mark them for next year's pruning or mount a trellis behind the raspberry plant and tie the canes to the trellis. In the following year, cut back any canes that are attached to the trellis and tie the new growth to it.