Cooperative Extension
MG Manual Home


Previous Previous

  MG Manual Reference
Ch. 8, pp. 27 - 30

[Pruning: fruit trees | other | small fruit ]

Training and Pruning Small FruitTop

For grapes to be most productive, they must be trained to a definite system and pruned rather severely. There are several training systems used. The two most common are the vertical trellis and the overhead arbor. Both of these are satisfactory in the home planting if kept well-pruned.
Of the many variations of the vertical trellis, the single-trunk, four-arm, Kniffin system is the most popular. Posts are set 15 to 20 feet apart and extend 5 feet above the ground. Two wires are stretched between the posts, the lower being about 2 1/2 feet above the ground and the upper, at the top of the posts. The vine is set between the posts and trained to a single trunk with four semipermanent arms, each cut back to 6 to 10 inches in length. One arm is trained in each direction on the lower wire.
During annual winter pruning, one cane is saved from those that grew from near the base of each arm the previous summer. This cane is cut back to about ten buds. The fruit in the coming season is borne on shoots developing from those buds. Select another cane from each arm, preferably one that grew near the trunk, and cut it back to a short stub having two buds.
This is a renewal spur. It should grow vigorously in the spring and be the new fruiting cane selected the following winter. All other growth on the vine should be removed. This leaves four fruiting canes, one on each arm, with eight to ten buds each, and four renewal spurs, one on each arm, cut back to two buds each.
The same training and pruning techniques may be effectively used in training grapes to the arbor system. The only difference is that the wires supporting the arms are placed overhead and parallel with each other instead of in a horizontal position. Overhead wires are usually placed 6 to 7 feet above the ground.
If an arm dies, or for any reason needs to be replaced, choose the largest cane that has grown from the trunk near the base of the dead arm and train it to the trellis wire. To renew the trunk, train a strong shoot from the base of the old trunk to the trellis as though it were the cane of a new vine. Establish the arms in the same manner as for a new vine, and cut off the old trunk.
Pruning may be done anytime after the vines become dormant. In areas where there is danger of winter injury, pruning may be delayed until early spring. Vines pruned very late may bleed excessively, but there is no evidence that this is permanently injurious.
Trailing blackberries and floricane fruiting red raspberry need some form of support. They may be grown on a trellis, trained along a fence, or tied to stakes. Primocane fruiting red raspberries should be supported with a simple trellis that can be easily removed prior to pruning.
A simple trellis, used in many home gardens for trailing blackberries and floricane fruiting red raspberries, consists of two wires stretched at 3 and 5 foot levels between posts set 15 to 20 feet apart. Fruiting canes are tied to these wires in the spring. Canes of trailing varieties are tied horizontally along the wires or fanned out from the ground and tied where they cross the wire. The trellis for primocane fruiting red raspberries consists of 4' long stake driven into the ground, 20' to 25' apart, with one string tied to either side. The canes are brought up in-between the strings. The string needs only to be tight enough to support the canes during the fruiting period.
Where stakes are used for support, they are driven into the ground about 1 foot from each plant and allowed to extend 4 or 5 feet above the ground. Canes are tied to the stake at a point about midway between the ground and the tips of the canes, and again near the top of the stake.
Canes of bramble fruits are biennial in nature; the crowns are perennial. New shoots grow from buds at the crown each year. Late in the summer, the new canes develop lateral branches with fruit buds on them. Early in the second season, fruit-bearing shoots grow from these buds. After fruiting, the old canes die, and new shoots spring up from the crowns. These fruiting canes may be removed any time after harvest. They should be cut off close to the base of the plant, removed from the planting, and destroyed. Some growers, as a sanitation practice, do this immediately after harvest. Most, however, prune during dormancy.
The dormant pruning is usually delayed until danger of severe cold is past and accomplished before the buds begin to swell. It consists of the removal of all dead, weak, and severely damaged canes, and the selection and pruning of the fruiting canes for the coming season. Where possible, fruiting canes 1/2-inch or more in diameter are selected.
Primocane fruiting red raspberries are cut to ground level after fruiting is completed in the fall. The row is narrowed to 12' to 16' at this time by tilling or other similar practice.
The following comments concerning red raspberries do not apply to the Heritage variety. Heritage and other ever-bearing red raspberries can be moved off and sacrifice the spring crop. The lowest will be delayed until late summer or early fall.
Red raspberries should not be summer-topped. At the dormant pruning, where the hill system of culture is used, thin until only seven or eight of the best canes remain per hill.
If the plants are grown in hedge rows, keep the width of the rows to 18 inches or less, and remove all plants outside the row areas. Thin the canes within the hedge rows to 3 to 4 canes per running foot, saving the best canes.
Pruning Raspberries
Pruning Raspberries
Black raspberries should be topped in the summer when the young shoots are about 24 inches high; purple raspberries, when about 30 inches high. Summer-topping consists of removing the top 3 to 4 inches of the new shoots by snapping them off with the fingers or cutting them with shears or a knife. Ideally primocanes are tipped above a bud so little dead wood is left between the wound and the bud. Where trained to supports, let them grow 6 to 8 inches taller before topping.
At the dormant pruning, thin each plant until only four or five of the best canes remain. Cut the lateral branches of the black raspberry to 9 to 12 inches long; those of the purple raspberry to 12 to 15 inches long.
Pruning Red Raspberries
Pruning Red Raspberries
New shoots of erect blackberries should be summer-topped when they are 30 to 36 inches high. To prevent the planting from becoming too thick and reducing yields, it may be necessary to remove excess sucker plants as they appear. This can be done either with a hoe or by hand. In the hedge row type of culture, leave only three or four shoots per running foot of row. Grown in hills, four to five new shoots may be allowed to develop in each hill.
At the dormant pruning, where supports are used, head the canes to 4 to 5 feet in height. Canes grown without support should be headed to 3 feet. Cut lateral branches back to 15 or 18 inches long.
Trailing blackberries require little pruning. All dead and weak canes should be removed after harvest or at the dormant pruning. They should be thinned to seven or eight of the best canes per hill, cut to about 5 feet in length, and tied to either a stake or trellis.

Pruning is the removal of parts of a woody plant for a specific purpose. These purposes include: training the plant; maintaining plant health; improving the quality of flowers, fruit, foliage, or stems; and restricting growth.

Search Index Comment

This site was developed for the Arizona Cooperative Extension, College of Agriculture, The University of Arizona.
© 1998 The University of Arizona. All contents copyrighted. All rights reserved.