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Pruning is the regulation of plant growth and productivity through branch removal and bud manipulation. Plants do not have to be pruned to stay healthy and bear well; they naturally prune themselves as branches die due to weather, insufficient light, insects and diseases. Pruning can help them remain more resistant to pests and disease, as well as bear a larger, more easily manageable harvest.
Shaping includes pruning, as well as tying branches or using weights to change the direction and hence growth habit of the branch.
1. Removing dead and diseased wood helps prevent infection and the spread of disease.
2. Pruning can improve both the quantity and quality of the harvest And unpruned tree may grow upward without bearing until the fruit is out of reach or tree is too large for the space. Unpruned trees may also over-produce one year, and subsequent fruit quality may be poor – pruning limits production to maintain a consistent yield of high-quality fruit and strengthens the tree against disease.
3. Good shaping works with a plant's natural growth habit to develop a strong primary structure that is able to support the full weight of harvests.
4. A narrow crotch angle is weak, and the branch may break under the weight of fruit or in a storm, possibly tearing deep into the trunk and destroying the tree - at 17 degrees or less the bark gets pinched into the crotch angle, trapping water and promoting rot. A crotch angle between 45 and 60 degrees is ideal, because the bark can develop fully.
5. Shorter trees and lower fruit growth make for easier harvesting.
6. Pruning limits vegetative growth, channeling more energy into fruit production. Shoots, water sprouts, and vertical branches drain a tree's energy. Suckers grow from below the graft union on grafted trees. When productive, the rootstock usually yields poor-quality fruit. If left unchecked, suckers can overgrow and shade out growth from the scion.
7. Sunlight to the interior of the tree is essential for flower bud formation and fruit ripening.
8. Increased air circulation to the interior prevents development of fungal diseases.
How, when, and what to prune will depend on what type of tree you are working with. Be familiar with your tree's growth habit (pyramidal, spreading, bushy, climbing, vigorous) so as to choose the pruning style best suited to the plant's natural growth tendencies. Also learn about it's fruiting habit; inadvertently pruning fruiting wood or specialized fruiting structures can seriously compromise a tree's ability to bear fruit.
Damaged and diseased wood, suckers and watersprouts should be promptly pruned, no matter what time of year.
Annual pruning should be done during the dormant season, before buds begin to swell, and preferably on a day when the temperature is above freezing (mid-February through March).
Some exceptions include...
Peaches should be pruned after they bloom. Very lightly thin them
again after they have leafed out so as to let more light into the
interior. Apples, pears, grapes can be pruned earlier, starting
in late December.
Thinning: To allow more light and air into the interior, cut small side branches back to their point of origin on the parent branch – a highly recommended technique.
Tipping: To induce horizontal branching, remove the terminal bud to a lateral bud heading in the direction you want branch to grow. Make the cut ¼” above lateral bud (to allow for dieback) and at an angle parallel to the direction of the bud.
Notching: By nicking vascular tissue above or below a lateral bud, you can determine whether a bud becomes a shoot or a flower. The nick should be close to the bud, about 1/8” wide, but not deep (a mere scratch - to cut the phloem just below the bark surface). It should reach halfway around the stem. To produce a shoot, notch above dormant bud, cutting off the flow of growth hormones from terminal bud. To produce a flower, notch below the dormant bud, sending the flow of carbohydrates from the leaf to the bud instead of the rest of the tree.
Other Shaping Methods
Spreading, bending: hanging weights (molded concrete hangers, water jugs, etc,), using clothespins in late May-June, tying branches to ground or mouse guards, or using various length sticks with deheaded nails in each end to widen branch angles, making branches more fruitful & fruit more reachable without cutting. If whip has no or too few scaffolding branches, bend it over as alternative to cutting! Always bend partially to side, not down, to prevent breaking.
Damaging Cuts – Do Not Use!
Heading: Cutting the branch to a stub, lateral branch, or side branch removes the terminal bud, resulting in a dense outer shell of weakly attached shoots. The tree's natural habit will be lost to bushy growth.
Shearing: One of the worst things you can do to a fruit tree is to remove a set length from all of the outer growth, in which cuts fall randomly above and below buds. Removal of the terminal buds causes flush of dense, bushy growth, which is fine for hedges, but can ruin trees.
Orchard Trees:
Note: never remove more than 30% of living wood
in one growing season or there will be a flush of vegetative growth
as the tree tries to restore its former food-producing capacity.
1. After removing dead and diseased wood, start with bending. Then,
use thinning cuts primarily, and tipping only to encourage lateral
branching.
2. Don't prune off fruiting spurs on apples, pears, apricots, and
plums. On peaches and sour cherries, thin the fruit-bearing wood
by removing twigs under 4-6”.
3. Keep the central area open by removing crossed and inward growing
branches. This increases light to interior and improves air circulation.
4. Prune for branch strength by removing branches with acute crotches
(less than 17 degrees between the branch and the main trunk). Encourage
wider angles by training narrow forks through spreading techniques.
Primary Structures for Strength and Harvest – Select the primary structure that best compliments tree's growth habit and fruiting habit.
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The modified central leader is an alternate method for trees with a strong vertical growth habit, recommended for cherries, pears, and some apples. 5-6 branches are left spiraling evenly up the trunk, 8-12" apart, but the trunk is cut back to a main branch at 5-8', and treated like vase. Open-center from that point. |
| Vase or open-center is used for tees with a spreading, vase-shaped growth habit (such as peaches, and plums). A whorl of 3-5 branches is left within 2-3' above ground; any main trunk is cut back to the topmost branch. |
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Use thinning cuts for a less bushy effect. This increases light and air circulation to the interior of plant. Remove stems on currants, gooseberries, hazelnut bushes that are more than 4 to 6 years old; older stems are less productive, so their removal enables younger stems to take their place. When pruning, cut stems to l-2” above crown of plant.
Grape Vines:
During the first year after planting, simply cut to 2-3 buds.
During the second year you must select a training system. If you have 2 wires, use the 4-arm kniffinmethod, if one wire, use single-curtain cordon method, if you have a fence, use the fan system to utilize the area of the fence. Decide on a height for the trunk and thin the plant to a single trunk. Cut back to just over the height of the highest canes you want.If no vine reaches the desired height, repeat simple first year pruning to focus energy from the weak roots into 2-3 good shoots, one of which will be chosen next year as the trunk.
During the third year select 4 vines of first year wood. Always choose thick, vigorous vines with at least 6” between nodes (places where this year's buds will grow). Cut them to 10 buds on each, then select 4 other vines and cut them to 2 buds each.
Each subsequent year select the 4 best vines (usually from the 2-bud stubs you left last year) and cut to 10 buds (for Concord grapes 15 buds is okay) for this year's bearing wood. Remove last year's bearing vines, but leave four 2-bud stubs to produce next year's bearing wood
To prune an overgrown vine select the canes to save, choosing from the canes which received the most sun during the previous season. They are usually darker in color and larger in diameter (at least as thick as a pencil). Cut Concord grape vines to the best 60 buds, cut less vigorous varieties to 40 buds (these are the maximum numbers for a mature, healthy plant, which lead to good quality grapes).
Making the Cut: primarily for pruning trees.
To removing a branch less than 1” wide you will make a single cut just outside the outermost ring of the branch collar. Start by locating the branch collar, which is a swollen area of compressed rings of bark tissue/wood at the base of a branch. It is the point at which the growth pattern of the trunk overlaps that of the branch, strengthening the connection of the branch to the tree as new growth is added each year. Branch collar tissue is the tissue that heals and closes over the wound made by removing a branch. It is also a storehouse of phenolic compounds which prevent fungal diseases from entering the plant while the wound is healing.
To prune a branch larger than 1” in diameter you will remove the branch in three cuts. This prevents tearing of the trunks bark as branch falls.
To top a tree (remove the main trunk):
Removing a co-dominant stem/trunk: Co-dominant stems/trunks do not have branch collars. The goal is to make a cut that the tree can defend and eventually close, so the cut is made relative to the branch bark ridge which runs down between the co-dominant trunks. Remove the unwanted trunk by making a diagonal cut starting at the top of the branch bark ridge and ending at a point level with the bottom of the branch bark ridge.
Growth Habit and Common Pruning Approaches:
| Pyramidal or conical (strong vertical growth) – Prune to a central modified leader. |  |
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| Rounded or Spreading (multiple leaders, horizontal branching) – Prune to vase/open center. |  |
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| Bushy (dense foliar growth) – Make thinning cuts to let in more light without inducing new growth. |  |
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| Leggy (insufficient light, understory plants) – Multiple heading cuts to induce a flush of dense growth. |  |
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