General pruning guidelines for semierect or erect blackberries:
Other than removing any broken canes or roots, little
pruning is done in the first year, though plants should
be trellised as soon as the canes are long enough to reach
the trellis wire. After the first
year, pruning is done twice a year. The first pruning
is in the winter. At this time, the lower side branches
that are below the lower wire are removed. The laterals
at the top of the trellis should be headed back to 12 to
15 inches. This will promote larger fruit by removing excess
fruit wood. The next pruning is done just after the harvest.
After harvest those canes that have born fruit are removed
by cutting them down to the ground. During the spring and
early summer though, replacement canes are growing out
of the crown. These new canes are gently bundled off to
the side, where they will continue to grow until the harvest
is complete. After the harvest, the new canes
that were growing from the base are trellised by
wrapping them around the top wire and back down to the
bottom wire in a fan shape.
Pruning raspberries:
On summer-bearing varieties, prune out spent fruiting
canes any time after harvest. Keep 10 to 12 of the
healthiest new canes and tie them to the top trellis.
Late during the following winter, tie canes or wrap
in a semicircle. This forces the lateral branches to
grow in at a convenient height. In April, remove the
first flush of new vigorous canes by cutting back when
the growth is 7 to 10 inches high. New canes will
develop shortly thereafter. This practice increases
yield. For fall-bearing raspberries, remove the top
half of the canes after fruiting, or remove the entire
cane to the ground. If you leave half of the cane,
you will get a summer crop the following June. If you
remove the whole cane, you get only one crop in the
fall, which is the preferred crop.
