Complete Guide: How to Prune Your Peach Tree in Summer 2024

Growth Habit of Peach

The successful pruner must understand how a tree grows and how it will respond to various types of pruning cuts. It is also important to observe the results of pruning. There are two types of buds on a peach tree. The terminal bud at the end of a shoot is always vegetative and produces a leafy shoot. Axillary buds develop during the summer at the bases of leaves on current season’s shoots and can be either leaf or flower buds. Peach flower buds are termed “pure” or “simple” because they contain only flower tissue. A peach flower bud produces a single flower that can set one fruit.

Each node (the point on the shoot where a leaf is attached) on a vegetative shoot may have from zero to 3 buds. Nodes at the terminal end of a shoot usually have single buds. The small, pointed buds are vegetative and the larger, rounder, and more hairy buds are flower buds. Many of the nodes on the lower two-thirds of a shoot have 2 or 3 buds arranged side by side. There can be any combination of flower (F) and leaf (L) buds (FL, FF, FLF, FFF), but most often a leaf bud is flanked by flower buds (FLF).

The number and distribution of flower buds on a shoot can vary with tree vigor, the variety, and the light environment that the shoot developed in. Results from a variety trial in New Jersey indicate that ‘Jerseyglo’ and ‘Springold’ had 20 to 23 flower buds per foot of shoot length, whereas ‘Harken’ and ‘Emery’ averaged only 15 flower buds per foot of shoot length. Shoots that grow less than 6 inches generally have the most fruit buds per inch of growth. The total number of fruit buds per shoot increases as the shoot’s growth increases to about 2 feet.

Figure 2. Short shoots less than 8 inches long have a high density of fruit buds, but produce small fruits (A), Shoots 12 to 24 inches long (B) are most productive. Long shoots that are branched (C) produce fewer flower buds.

Moderately vigorous shoots have a high proportion of nodes with 2 flower buds. The leaf buds at most nodes develop into lateral shoots that may be fruitful in subsequent years. A number of axillary buds on vigorous current season’s shoots (greater than 2 feet long) grow to produce secondary shoots. Such shoots are not very fruitful because fruit buds do not develop at many nodes on secondary shoots.

The ideal fruiting shoot is 12 to 24 inches long and 3/16 to 1/4 inch thick at its base, and it has no secondary shoots (Figure 2). Proper pruning, fertilization, irrigation, and fruit thinning must be practiced to ensure enough shoot growth each year to produce adequate fruit buds for the following season.

Results from experiments in Virginia indicate that fruit size is related to shoot length (Figure 3). Short shoots tend to produce small fruit because short shoots have too few leaves to support the growth of fruit. Therefore, shoots less than 6 inches in length should be removed while pruning.

Figure. 3. Fruit size (fruit weight) increases as crop load (fruit/square centimeter of trunk cross-sectional area) declines from 10 to 2 fruit/square cm, and fruit weight increases as shoot length increases from 6 inches to 30 inches.

Pruning to Obtain the Open-center Tree

Peaches are typically pruned to an open-center, or vase, shape. Peach trees are easily trained to this form and this shape allows relatively good light penetration throughout the tree. The resulting low, spreading form also facilitates thinning, pruning, and harvest from the ground. Young peach trees must be pruned carefully to develop and maintain fruiting wood near the tree center. The fruiting surface of poorly pruned trees will move farther from the tree center each year, which results in reduced yields and increased production costs. Although pruning may vary depending on the specific objectives of individual peach producers, the following guidelines can be followed to develop the low, spreading, open-center tree form.

A mature peach tree trained to the open-center form actually consists of a doughnut-shaped canopy, about 5 or 6 feet in depth and about 5 or 6 feet from the inner wall to the outer wall of the canopy. This “ring” of fruit producing canopy can be located close to the ground if trees are pruned each year to minimize tree height and to encourage light penetration into the canopy. If trees are not pruned carefully, the fruiting zone will move 10 to 12 feet above ground. Such trees produce yields slightly greater than shorter trees, but tall trees are expensive to manage because ladders are required for pruning, fruit thinning, and harvest. Branches on tall trees may also have a tendency to break under the weight of a heavy crop.

There are two types of pruning cuts. “Heading” or “heading back” cuts involve shortening a limb by cutting the end off. Heading cuts remove the terminal buds that produce plant hormones that normally inhibit shoot development below the terminal bud (Figure 6). During the growing season several vegetative buds just below the heading cut will develop into vegetative shoots. Heading cuts are used to shorten branches, stiffen branches, and induce branching. Avoid using heading cuts on the tree periphery because the proliferation of vegetative shoots forms a layer of foliage that shades the tree interior. Heading cuts are most useful for inducing branching along the trunks of newly planted trees. “Bench cuts” are a special type of heading cut, and involve removing the terminal portion of a branch just above a side branch. Bench cuts are sometimes used on peach trees to develop a low spreading tree. “Thinning” cuts involve removing part of a limb at the point where it is attached to a major branch or to the trunk. Thinning cuts do not induce vegetative growth near the pruning cut and are usually preferred for minimizing tree size and for removing excess shoots.

Figure 6. Heading cuts stimulate shoot development below the cut. Thinning cuts induce little vigorous shoot growth. Bench cuts may be used to produce a low and spreading growth habit.

Pruning at Planting: Peach trees are pruned at planting to balance the tree top with the small root system and also to induce branching on the trunk. Fall-planted trees should be pruned the following spring. The height of the scaffold limbs above the ground can be varied by the height of the heading cut. It is preferable to have scaffold limbs originating 20 to 24 inches above the ground to facilitate herbicide application, grass mowing, and other orchard practices.

Small trees, particularly those from southern nurseries that are “June-budded,” usually have no side branches and should be headed at 24 to 30 inches above ground. Trees that are budded in June are small because they grow for only three months. August-budded trees are larger because they grow for about five months during the season following budding. The scaffold branches will develop within 4 to 6 inches below the cut. Larger trees usually arrive from the nursery as branched whips. Since most of the side branches are weak, they should be pruned to 2 or 3 buds. Shoots often develop from these stubs and may be suitable for major scaffold limbs. Strong branches with wide crotch angles should be pruned to 6 or 7 buds and can be retained for scaffold branches. The height at which branched trees are headed depends on the size of the tree and positions of good side branches. Trees 3 to 6 feet tall can be headed at 24 to 30 inches above ground. Larger trees must usually be headed at 3 to 4 feet because low side branches on the trunks are damaged or removed for shipping.

An alternative method of heading unbranched large trees involves heading trees at 10 inches above the ground. This will allow the tree to grow a new central leader from which scaffold branches can be selected during the first winter. Preliminary research results indicate that about 10% of large trees (trees with trunks more than 3/4 inch in diameter) may not survive the severe heading, but little tree mortality has been observed with moderate size trees.

The First Summer: Pruning the first-year tree during its first summer can be an effective method of developing the tree frame. Trees should be pruned at least once and possibly two times during the summer before growth ceases. Summer pruning will reduce the amount of dormant pruning required the first winter and will direct growth into the desirable scaffold branches. During May and again in July, low shoots on the trunk should be removed to a height of 20 inches. All shoots that form angles of less than 45 degrees with the trunk should be removed. Vertical shoots that are unacceptable as scaffold branches should be removed. A spreading growth habit can be encouraged by pinching upright-growing shoots back to an outward growing bud or secondary shoot. Pinching is actually a type of bench cut. Pinching should be done in late June and/or July while shoots are actively growing.

There is a new method of pruning first-year trees that seems very promising. Do not remove the top few shoots with poor crotches. Instead, head the top several shoots by half in early June. Growth of the headed shoots is suppressed and growth of the lower shoots that have wide crotches is encouraged. The small “bush” in the tree center is removed during the winter.

The First Winter: At the end of the first season, some trees will have many desirable limbs, and others will have limbs on only one side or may have vertical growth habits and upright leaders. The first winter is the most critical time to select branches that will develop into a strong framework capable of carrying heavy crops in the future.

If trees were pruned during their first summer, very little pruning will be needed during their first winter. The trees should begin to resemble an open-vase. Remove branches on the trunk below the 20-inch height. Remove branches that form angles of less than 45 degrees with the trunk. Branches with narrow crotches are weak because bark extends into the crotch, and branches may split from the trunk. Narrow crotches are also susceptible to winter injury, cytospora canker, and borers. Unless they form a strong, wide crotch, remove 1 of any 2 limbs of equal size that tend to divide the tree and form a Y (Figure 7).

Figure 7. A “V” crotch is weak and susceptible to splitting, winter injury, and canker. One branch should have been removed during the first winter to avoid the weak crotch.

Since all peach trees do not grow alike, there are at least two basic methods of developing an open-center tree that has a strong framework, and they seem to be equally effective. The most common method involves selecting 3 primary branches with wide crotch angles and that are spaced evenly around the trunk. Some trees will not have 3 acceptable limbs at the end of the first season, but excellent trees can be developed with only 2 main branches. Sometimes, 4 to 6 desirable limbs will grow at one point on the trunk. It is best to remove all but 3 of these branches because there will eventually be 3 dominant limbs and the others will be squeezed out.

Another method of developing an open center form is to head the tree at 3 to 4 feet at planting; this is often preferable with the larger nursery trees. Select 3 to 5 limbs that are distributed evenly on the trunk and spaced 4 to 6 inches apart vertically. After the first year’s growth, peach trees with 3 main branches at 24 to 30 inches above ground look quite different from those that have 4 or 5 main limbs extending to 4 feet. However, as these trees grow for several years and are trained to the open-center, they will appear much more uniform. Avoid horizontal limbs on young trees because they will bend downward with the weight of a crop and will eventually need to be removed to allow equipment to move under the tree. Watersprouts (upright shoots developing along the upper side of a branch) will also arise along the top of a horizontal limb. An angle of 40 to 50 degrees from the vertical is most desirable. Remove root suckers, downward growing shoots, and strong vertical shoots that shade the tree center. Keep the tree balanced by shortening the strongest branch. Retain as much of the tree as possible, including the smaller side shoots growing from the selected main branches. Head the scaffold limbs above an outward-growing secondary shoot to encourage a spreading growth habit.

Sometimes a tree will produce a strong shoot from the soil line and the rest of the tree is weak or dead. If the shoot originates below the bud union, it is the rootstock and the tree should be replaced. If it develops from above the bud union, it should be pruned to a strong shoot. Secondary limbs with wide crotches developing at the appropriate height on these shoots can be selected as scaffold limbs.

The Second Summer: Although it is not necessary, it is highly desirable to prune trees during the second summer to improve light penetration into the tree center. Shoots developing on the trunk below the scaffold branches should be removed in June. Remove vigorous upright shoots developing near the tree center. By late June, when secondary shoots develop on terminal shoots, the upright portion of the terminal shoot can be pinched just above an outward growing secondary shoot. This will encourage the spreading growth of the tree and direct growth into the desired secondary shoot. Summer pruning should be completed by early July.

The Second Winter: Peach trees that have grown well for two years may be 5 to 7 feet tall, 6 to 8 feet wide, and have trunks 3 to 6 inches in diameter. Such trees will also have numerous flower buds, and, if pruned moderately, may produce 20 to 40 pounds of fruit during the third summer. Excessive pruning will reduce yield the third summer.

Each tree should have 2 or more well-spaced, scaffold branches with wide crotch angles. If this is not the case, try to select appropriate scaffold branches and remove all others. Remove all large watersprouts that tend to grow through the tree center. Scaffolds that have made less than 30 inches of growth and have several side branches should be pruned to leave 2 or 3 well-spaced side branches. Shoots developing on the lower sides of scaffold limbs should be removed. If these shoots fruit, the extra weight will pull the scaffolds down so that they interfere with herbicide application. Retain most of the other one-year growth throughout the tree.

Sometimes 2 shoots of equal size will develop near the end of a scaffold branch and will form a V crotch. Such crotches are weak, and one shoot should be eliminated. The terminal ends of scaffold branches often grow upright. In the event that a scaffold develops a vertical orientation near its tip, it may be turned out by pruning to an outward growing secondary shoot. This type of bench cut is preferably performed during the summer but can be performed during the winter.

The Third Summer: Trees develop best when low branches and watersprouts are removed in June. Upright portions of terminal shoots should be pinched just above an outward growing secondary shoot to encourage the spreading form.

The Third Winter: After the third season, peach trees are usually 6 to 9 feet tall, 7 to 9 feet wide, and have trunks 4 to 7 inches in diameter. During the fourth summer, peach trees may produce 50 to 80 pounds of fruit. Trees should be pruned the same as during the second winter to maintain a low spreading form. It is most important to remove watersprouts, low branches, and excess fruiting shoots.

Summer Pruning: The Key To A Healthy Fruit Tree

FAQ

Is it okay to prune a peach tree in summer?

What happens if you prune a fruit tree in summer?

Summer pruning fruit trees helps control unwanted growth and manage the overall structure and size of the tree. Unlike winter pruning, which stimulates new shoots, summer pruning relies on thinning cuts that reduce energy production.

What happens if you don’t prune a peach tree?

Pruning peach trees is vital to the health and productivity of a peach tree. While a peach tree will grow just fine without pruning, the quality of the fruit and the health of the tree will be significantly diminished.