Fruit tree pruning.
January 17, 2011
Mid February is the best time to prune fruit trees in North Texas. It is best to wait until winter is almost over. Do not prune when wood is frozen since freezing causes brittle wood. The main reason for not pruning in the fall or winter months is that the possibility exists of selecting poorly matured wood for main branches. This poorly matured wood may then die in the winter causing a reduced yield in the next growing season. After winter exposure dead wood can be easily recognized as dark, brittle and sapless and can be removed. Late spring pruning may cause sap bleeding or weeping, but it is better to prune late than not to prune at all.
In general there are two methods to pruning trees - central leader system and open center system.
Central leader system – let the main trunk grow upward with limbs coming off the main trunk. Limit the branches to the number that produces well for that species. Remember that too many branches will result in smaller fruit.
Prune the branches that come off the main leader so that there is a spacing of at least 8 inches, but no more that 2 feet, between limbs. Spacing the branches is where the “art” comes in. You just have to stand back and look at the tree to see where to cut so that the tree has a balanced look.
The 1st year of training usually produces a tree with one branch – occasionally two – and a leader. Cut back very long leaders to about 20 inches. New lateral branches will grow from the leader next year. From these you can choose another scaffold branch or two. As the tree grows older and higher, cut the top off at about 10 feet. Make such a cut at the junction of a lateral branch. This form is then known as the modified leader.
Open center system – When you cut the main leader/trunk, cut it so that the center will remain open. Since this does not happen in one year, you will need to keep cutting the branches back in the center of the tree so that no main trunk develops above where your scaffold branches come off the tree. You will want to select the branches to be saved in a symmetrical pattern. In other words, leave branches as evenly spaced around the tree as possible. Limit the branches to what you think the tree can support and also yield good fruit production. Again, remember, too many branches mean smaller fruit.
Apple — Central leader system. Apples tend to have very narrow crotch angles; the branches come off the tree at an angle that is too upward-growing. These angles need to be increased by spreading the branches. This will cause the tree to have a more spreading look instead of being upright and narrow.
The picture below shows correct and incorrect pruning of an apple tree.
Cherry — Central leader system. Cherries are vigorous growers and need frequent pruning. They do need some spreading of the limbs as they tend to grow too upright with not enough spreading. Also, spreading the limbs prevents some winter injury. Try to balance the growth of the central leader with the growth of the branches. Each year prune to balance the growth. By cutting back the scaffold branches you will have better shoot growth. The shoots are where the fruiting buds are located, so you want good shoot growth each year.
Citrus — Citrus trees do not need much pruning, but some is necessary. Semi-annually, prune to remove suckers that grow from the base of the tree. You need to keep removing these suckers or they will take energy from your tree. Remove any dead or diseased limbs. Remove any crossing limbs. Pruning is best done after fruiting and before flowering.
Fig — Most fig trees are never pruned and produce many figs. But a little pruning can help your fig tree. If you buy a large fig and the roots receive any damage, prune the top back about the same percentage as the roots were damaged. This will help the tree recover from transplanting. As your tree grows, remove any limbs that are growing toward the ground. Also, remove any branches or limbs that are growing too close together.
On mature fig trees you can cut back the tips of the main trunks three to six inches in late winter to produce larger, sweeter figs. Do not try this on young trees as you will restrict their development. Also, remove any dead or diseased wood.
Peach & Nectarine — Open center system. Peaches are one of the most common fruit trees for home growers in Texas. They are also one of the trees that are most commonly incorrectly pruned or not pruned at all. Not pruning will result in a diseased tree that will die within a few years from overproduction of vegetative growth and small fruit.
With peaches and nectarines, heavy pruning in the spring is necessary to get the best crop and have a healthy tree. Peaches bear fruit on year-old wood, so prune for good production. Prune out all hanging branchlets. Hanging means the branch is pointing toward the ground. Prune out any crossing or dead wood. Look at the tree and remember that you want the center open for good light penetration. Because most of the new growth will be in the top of the tree, that is where you will do most of your pruning. Keep the tree at a manageable height. You want the scaffold branches going out and slightly upward. Head-back the scaffold branches each year so they do not get too long.
Pruning out too little wood is the most common mistake in pruning peach trees. If you have trouble determining how much wood to remove in the early spring, wait until the trees are in bloom and prune back where you see too many blooms. You want the fruit no closer than about three inches apart. So prune accordingly. Pruning too much will result in larger fruit so that is really not a problem.
Pear — Central leader system. Pear trees need little pruning but since the branches generally have narrow crotch angles a little spreading of the branches is useful to produce a more spreading tree. When you prune a pear tree, you will see water sprouts (vegetative growth at the cut sites) and the terminal growth increase. Both these things are undesirable. Fireblight is a major problem with a lot of pear varieties and any cuts will increase the chance of blight entering the tree through a cut. Applying a wound dressing to all cuts on a pear tree is necessary to help with healing and fireblight prevention. But you will need to remove any rubbing limbs, water sprouts and damaged or dead wood.
Plum and Prune — Open center system. Prune to create an open center on young plum trees. Once you have established the open center with no central leader, you can cut back on your pruning in later years. Prune out small branches, dead and crossing wood annually. Thin limbs throughout the tree to maintain good light penetration. Pruning plums is necessary on an annual basis, but only prune on a limited basis. Plums do not need near as much pruning as peaches.
Pomegranate — Natural with some training. Pomegranates need to be pruned to establish shape when young. Nearly all pomegranates are on their own roots, so any growth from below ground level will be true to variety. Prune to two to three main branches/trunks in most areas of Texas. Pomegranates tend to sucker a lot in the early years and these suckers need to be removed at least twice a year, in late spring and early fall.
One-year-old canes which are selected for fruiting should be stocky (no larger than the size of a large pencil) and should have plump, vigorous buds. These four canes should arise as near the trunk of the vine as possible and immediately beneath the trellis wire on which it will grow. Renewal spurs should be provided near the base of each cane. The selected canes should each contain 8-10 buds.
Remove all surplus wood, including the suckers, leaving four one-year-old fruiting canes and renewal spurs of two buds at the base of each. Canes growing from the renewal spur will produce the fruiting canes from which you will select 8 to 10 bud arms (canes) for next year’s production. By using this technique, fruiting canes are kept near the trunk of the vines. Remember that because of the grape vine’s characteristic of vigorous growth severe pruning is necessary. Approximately 90 percent of the entire vine must be removed yearly.