Pruning

Pruning fruit trees is an art. A strict rule is not to prune too much, especially in the early years. The tree should be trained in the first year or two so that it will begin to develop into its proper shape. Select branches with wide crotch angles. In the third to sixth years, very little pruning may be needed. Over-pruning will delay bearing.

Prune in late winter or early spring. Summer pruning of small twigs is also a good practice and helps to keep tree size down. Each spring cut out all dead and broken branches. During the first two years, select branches spaced at intervals along the main stem. Cut off all branches lower than 20 inches. A short trunk and closely spaced lateral branches will aid in developing a small, compact tree.

Train the tree so that it has a central leader which is taller than the other side branches. Shape it like a Christmas tree. A 5-year-old tree should have 5 to 7 side branches, well spaced around the main central trunk.

You may need to partially shorten the leader and to remove some of the high central branches to prevent the tree from growing too high. Heavy cropping tends to deter too much branch growth.

Trees on dwarf rootstocks have less excessively vigorous growth than trees on seedling roots. Pruning itself has a dwarfing effect on the tree. Sometimes, dwarf trees need very little pruning.

Cut out branches which cross each other, as well as vigorous upright suckers in the middle of the tree. Thin out parts of the tree which are too thick and which hamper penetration of chemical sprays and sunlight.

Make pruning cuts flush with the main limb, without leaving stubs. On young trees no healing paint is necessary.

Crotch angles of some varieties, especially spur type Delicious, tend to be vary narrow. The branches grow almost straight up, close to the center of the tree. These should be spread out in the first, second, and third years and later if necessary.

Spreaders should be placed before you make pruning cuts. Cut a thin lath board about 18 inches long with V cuts on both ends. The V on one end is braced against the central leader and the other against the branch to force it outward to an angle of about 45 . Branches can also be forced outward by loosely tying their tips to a stake driven firmly into the ground. Clothespins or No. 9 wire 6 to 16 inches long and sharpened on both ends also are very effective in spreading small branches. Spreading of branches discourages too much vigorous tree growth and also induces early fruit production.

Dwarf trees can also be trained on a wire trellis similar to grapevines.

Fertilizer

Beginning with the second year, apply fertilizer annually about two weeks before bloom. It must not be applied in mid to late summer because this stimulates late summer growth which will be too tender and result in winter kill during very cold winters.

Ammonium nitrate at 1/4 pound per tree multiplied by the number of years the tree has been set, but never more than 2 1/2 pounds per tree, is applied to moderately fertile soils. Very fertile soils need less.

The quantity of fertilizer is also adjusted according to the tree's vigor. If shoot growth the previous year was more than 12 inches long, less fertilizer will be needed.

Too much nitrogen causes excessive branch growth, inhibits fruit set, causes poor fruit color and flavor, delays ripening, and encourages fire blight disease. Conversely, pale green or yellowish leaves in the summer and short shoot growth may indicate the need for more nitrogen fertilizer the following spring.

Phosphorous fertilizer generally neither benefits nor harms apple trees. If the soil is low in potassium, apply some.

A 10-10-10 fertilizer at three times the above rates of ammonium nitrate is an equally good substitute.

Fertilizer is scattered under the outer parts of the branches. Since ammonium nitrate dissolves easily, you don't need to dig holes in the soil.

Stable manure can be used instead of chemical fertilizers, but it is usually more expensive and less available.

Mulches of any plant material, such as straw, grass or sawdust, suppress weed growth, hold soil moisture during a dry summer, maintain favorable soil temperatures, and add organic matter to the soil. Mulches should be six inches or more deep and extend to the tips of the branches. Woody materials, such as sawdust, wood chips or coarse hay, will require extra nitrogen fertilizer to aid decomposition. Mulches may harbor harmful mice in winter.

Thorough irrigation benefits fruit trees in midsummer when little rainfall occurs. Watering is especially important at planting time and during the first summer. In Western States, of course, fruit trees are almost always irrigated every summer.

Frost (28 F or lower) occurring after bloom kills all the blooms and young fruit and there will be no crop. Frost injury to blossoms occurs most frequently in the low parts of a valley, because cool air is heavier than warm and it drains to the low areas.

On a sloping hill there may be good air drainage and less damage will occur. Trees near houses in suburban areas will suffer less frost damage than those in rural areas. Late blooming varieties, such as Golden Delicious or Rome Beauty, sometimes escape late spring frosts.

Frequently there is little the home orchardist can do to protect against frost.

Pest control is one of the most difficult aspects of growing your own fruit. It is not possible to produce usable apples without applying chemical sprays. Pears do better. When pears are grown without insect control, it is often possible to use about half of the fruits.

Insects which can be really serious problems on apples include the codling moth, apple maggot, red-banded leaf roller, tent caterpillar, aphids, mites, and apple tree borers. Serious diseases include apple scab, powdery mildew, and fire blight. The home gardener usually must accept less than complete control or apply more spray than is actually needed.

Mow the orchard weekly so that tall grass and weeds do not compete with the trees for soil moisture and nutrients. Fertilizers do not reduce the need for grass and weed control, but mulches and herbicides can be useful in helping control weeds. Modern herbicides can kill all grass without damage to the trees. If weeds are controlled, no soil cultivation will be needed.

Meadow mice and rabbits can chew off the trunk bark. If the bark is chewed completely around the trunk, the tree will die unless it is bridge grafted. Crushed stone packed around the base of the trunk, and wire guards of 1/4-inch mesh screen made into a tightly closed cylinder 1 1/2 feet high and 6 inches in diameter wrapped around the base of the trunk, can help control mice. Rodenticides are sometimes used.

If the orchard is near a wooded area, deer may chew off the growing tips of young shoots. Tankage, a pulverized animal slaughter by-product, in a small cloth bag hung in the tree sometimes helps to repel deer.

Birds may peck into early summer apples which ripen from mid-July to mid-August, and can cause serious damage. Late ripening varieties are not injured by birds.

Thinning is necessary when too heavy a crop of fruit is set. It results in larger, better colored and higher quality fruits.

Prevent too early cropping by removing all fruits just after bloom in the spring of the first and second years. This encourages maximum early tree growth. Fruit removal from the leader will encourage an upright leader.

Up to five or six years of age, apple trees usually do not overset. But after six years, thinning may be needed. Reduce the crop to a fruit per spur, spaced 4 to 6 inches apart.

By thinning in the years of excessive fruit set, alternate cropping varieties such as Baldwin and Wealthy can be forced into a more consistently annual cropping behavior.

Harvest when fruits begin to drop and soften or become fully colored, and have developed good eating quality. Early summer apple varieties tend to ripen unevenly, and several pickings over a 2-week period may be needed, but the fruits on individual trees of late varieties all ripen at once.

Certain varieties such as McIntosh begin to drop even before they ripen. Others such as Cortland will not drop, even long after they have become overripe.

Harvest Bartlett pears before they begin to turn yellow. Ripen them at room temperature off the tree in the basket.

Yields of fruit trees will vary, depending on such factors as pests, rootstocks and variety. Fruit buds for the 1979 crop develop on the tree beginning in June, 1978, and they require adequate foliage for proper flower development.

Some varieties such as Golden Delicious crop at a young age, often 3 years, but others, such as Northern Spy, are much less precocious, often beginning about the 8th year.

Mature apple trees on dwarfing rootstocks usually produce 1 to 2 bushels per tree. On seedling roots, 15-year-old trees may bear 5 to 15 bushels.

Pear trees may produce half the volume of fruit borne by apple trees.

Storage of early ripening summer apple varieties is generally not practical, but late October varieties store well. Such apples store best at 31 F at high humidity and will stay tree-fresh through the winter. A home fruit storage can be made from a large garbage can or a large discarded home refrigerator buried in the ground with its door at the surface. In the case of a refrigerator, the lock must be removed to prevent children from accidentally being trapped inside.