I am often asked when the time is best for pruning fruit trees. The answer is “late winter or early spring while they are still dormant” — with the added disclaimer, “Do it when the weather is good.” There is no specific “ideal” date for pruning fruit trees so unless you have an orchard with 500 trees and only so many months to do the job, why put yourself through the misery of spending a cold, snowy day outside to do the deed? The trees don’t break dormancy until the weather gets warm.

Since the weather is getting warm, and we are only two weeks away from spring, you might consider doing it soon. If you are uncertain how to do it, read on. If you are a visual learner, or would like to see how it is done as well as reading about it, you might like to attend the free hands-on pruning demonstration tomorrow. Linden Greenhalgh, Tooele County’s USU Extension agent, and Larry Sagers, USU Extension horticulturist, will demonstrate pruning fruit Friday, March 6 at 10 a.m. Meet at the “Garden of Erda” at 812 E. Bates Canyon Road in Erda. Coming from Tooele, turn right at the second stop light on SR-36 in Erda and drive east for about a half mile. For more information, contact the Extension office at 277-2400.

The first question for most pruners is “How do I know which branches to cut off?” Choosing exactly what branches to remove from any given tree is a one-by-one decision. However, if you think of pruning fruit trees as a method of training them, it becomes easier to determine how to do it.

Tree pruning involves removing or training certain parts of a tree to regulate its shape and enhance fruit bearing without inhibiting healthy growth and development. Done correctly, pruning will invigorate fruit trees and make them more productive and stronger. It also removes plant parts damaged by diseases or insects. Training your fruit trees is essential if you intend to grow high quality fruit in the backyard orchard. Properly trained trees have strong trunks and branches that support the fruit and will not break down with the snow or wind. They also collect the sunlight to nurture the plant and make sweet, large and tasty fruit.

All fruit trees, regardless of their training system, need certain basic pruning care. The following general guidelines apply to most trees. Guides for specific trees follow these.

• Prune whenever it needs to be and can be done. Generally prune in March or April unless a severe winter threatens to limit fruit production. In that case, prune after fruit buds begin to develop.

Enjoy the lovely blossoms of spring blooming ornamental fruit trees like flowering plums, crabapples, pears and cherries before pruning them. The objective in pruning spring blooming trees is not fruit production, so prune them to shape them after flowers fade.

• Begin by cleaning up the tree. Remove dead, diseased and broken branches whenever they occur. Dead branches provide an avenue for insects and diseases to enter to cause further problems. Remove water sprouts (long, fast-growing branches that go straight up with wide distances between the nodes) and suckers (similar branches that extend up from the root.) Remove branches that rub or cross each other, and weak, drooping and unproductive branches. Let in light by removing branches that compete with other branches for light, shade the center of the tree, or grow back in toward the center of the tree.

Make all pruning cuts next to the collar (the wide portion of the branch that spreads where it attaches to the trunk or other branches). Do not leave a stub or cut into the collar because it will not heal over properly.

• Don’t seal or treat cutting wounds. Sealants tend to damage trees, which are capable of healing themselves. Unlike the finite supply of blood in animals, trees have unlimited supplies of the moisture absorbed by the roots that transfers up the tree and flows out of cut surfaces. As plants break dormancy, oozing stops.

• If crops look light, prune lightly to save as much bearing wood as possible. If they look heavy, heavier pruning is permissible. Never remove more than one-third of a tree at a time. Pruning developing blossoms won’t harm the tree.

• Good pruning equipment makes the job much easier. Look for quality long-handled pruning shears, smaller hand shears, and a pruning saw — generally a curved one with an 8- to 15-inch blade — and a stable ladder. Three legged ladders are exceptionally good for pruning because you can get in closer to the tree using the tripod form to slide between the branches.

• Prune fruit trees yearly. The purpose of pruning is to thin branches and reduce the height of trees to let the sun penetrate. Keeping trees a manageable size and volume makes spraying for pests more effective and picking safer. Prune from the ladder you will harvest fruit from. Extra branches and fruit that are out of reach are wasted at best and a hazard at worst. It is tempting to extend your stretch too far and take a chance on an accident.

• Begin pruning and training small trees the day they are planted and continue to maintain them yearly thereafter.

Pruning by tree type

By their natures, some trees need more extensive pruning than others. Some respond best to one system of pruning and others flourish under a different method.

Pomes are fruits with multiple seeds like apples and pears. Fruits form on a two-year cycle. The first year, buds form and the second year the fruits differentiate. The fruits form on their stems attached to the end of a spur — a separate small woody stem attached to the branch. Those spurs continue to grow longer and produce fruit every year. Protect those spurs for best fruit production. Spur-type apple trees develop long limbs with only a few side branches and many fruiting spurs.

Peaches, apricots and other stone fruits grow on stems that are attached to the sides of branches. They form on one-year-old wood.

In terms of pruning, this means encouraging and developing spurs on pome fruits and constantly cutting stone fruit trees to keep an adequate area of prime, new fruit producing wood.

The modified leader system is ideal for semi-dwarf or spur-type apples and also pear trees. Such a tree has one main trunk with tiers of branches spaced vertically along it. To train a tree to this system, cut the newly planted tree back to 30 inches high, just above a healthy side branch or just above a bud. One central branch should grow up as a new trunk through the season.

The lowest tier of branches should be 24 to 48 inches from the ground, extending out in four directions as nearly perpendicular to each other as possible. The next tier of scaffold branches should be 18 to 24 inches higher. They should also come out in four directions perpendicular to one another, but ideally they should be spaced between the lower tiers if possible. Continue developing tiers until the tree reaches the desired height. Generally, the tree will have about three layers of branches and will be 15 feet high. The branches should form 40- to 90-degree angles with the trunk. If the trunk angle is too narrow, put braces between the branch and the trunk for a season to force the branches out wider.

The number and spacing of the branches and the height of the leader varies with the type of tree — semi-dwarf, dwarf, apple, cherry, pear or plum.

The open center system is ideal for peach trees. The trunk extends about 18 to 30 inches high. From there develop three or four scaffold branches, all at nearly the same height from the ground and spaced as uniformly as possible from each other around the tree. Keep these about the same size by pruning. Scaffold branches form a crotch angle of 40 to 90 degrees with the trunk. Do not let the branches develop sharp vertical angles or they will be weak and split under a heavy fruit or snow load. The idea of an open-center tree is to keep all of the extra wood out of the center of the tree. Prune so the branches point to the outside of the growing area so the trees spreads out rather than growing upright.

Keep the open center, or vase tree, low for easy picking, spraying and pruning. The open center allows light to the center for forming and coloring fruit.

If you have a tree that was already shaped to a different system than outlined for a particular tree type above, work with the established system — do not try to change it.

In general, peaches and nectarines require the most pruning. Next are Japanese plums, apples, apricots, sour cherries, European plums and sweet cherries. Do not prune cherries much at all. They are large trees by nature, so do not try to control growth by pruning. Pruning too heavily encourages the growth of water sprouts — long, willowy upright branches that grow straight up and do not form fruit. These trees tend to grow long, upright branches in any case. Simply prune off branches that interfere with one another or grow too close together. Watch during the growing season and if upright sprouts grow too long, clip them back to a bud to encourage side branching.

Generally, prune pie cherries to the open center system. These trees are quite brittle and tend to grow at very narrow angles. Train the branches to wide angles while they are small.

Train apricot trees to either the open center or the modified leader system. They do not require a great deal of pruning. Because they blossom so early, spring frosts often limit fruit production. You may wish to delay pruning until after they blossom.