Advantages of homegrown pome fruit are numerous. You can grow varieties that are not readily available in grocery stores, control the level of pesticides used, and gain a greater understanding of the processes of nature that interact with the tree to produce these wonderful fruits. Remember, however, that producing high-quality apple and pear fruit requires careful observation as well as knowledge of how to respond to various pest problems that you may encounter.
Because apples and pears have many insect and disease pests, growing quality fruit in Pennsylvania is difficult without some pesticide use. Home gardeners are encouraged, however, to purchase disease-resistant varieties if they are available. Although these varieties are not resistant to all diseases that occur in Pennsylvania, they are resistant to the major ones. Pesticides still might be required, particularly in wet seasons, but their application rates can be reduced greatly. Under normal conditions, a home gardener might have to apply pesticides six to ten times to produce fruit of reasonable quality. If scab-resistant apples are planted, a gardener might need only two to three pesticide applications to produce quality apples.
The soil should be prepared thoroughly by deep cultivation either by hand or with a rototiller before planting. The soil pH should be maintained between 6.0 and 6.5. Have a soil test taken and make the recommended adjustments before planting. You can get information on soil testing from your county extension office.
In the absence of a soil test, lime a 10-by-10-foot area where each tree will be planted. Dig each planting hole wide enough to accommodate all of the root system without bending or bunching it, and deep enough so that the bud union of grafted plants will be no more than 2 inches above the ground line after the soil settles.
Keep root pruning to a minimum, but cut off all broken or mutilated root parts with pruning shears. Set the plants with the graft or bud union no more than 2 inches above the soil line (Figure 4.1). Work the soil in and around the roots. When the hole is half full, firm the soil with your feet before filling the rest of the hole. When the hole is full, pack the soil firmly. Do not leave a depression around the tree. Also, do not place fertilizer in the planting hole or fertilize the soil immediately after planting. Fertilize only after the soil has been settled by a drenching rain.
After planting, apply sufficient water to thoroughly soak the soil around the tree roots. This watering will help to bring the soil into closer contact with all sides of the roots and eliminate air pockets around the roots. Remember that approximately one-quarter of the root system was removed when the tree was dug. To compensate, remove the top quarter of the plant to reestablish the plant's previous shoot-to-root ratio.
On branched trees, remove poorly spaced and narrow-angled branches. Leave branches that are wide angled and arranged spirally about 6 to 9 inches apart up the leader (trunk). Branches left on the tree should be reduced by up to one-half of their length, and the leader should be cut about 12 to 15 inches above the top limb. Cut the leaders on nonbranched whips back to three-quarters of their original lengths.
Watering the young tree in late June might be desirable, depending on the rainfall up to that time.
If less than 4 to 5 inches of rain have fallen since the trees were planted, pour 5 gallons of water around the base of each tree.
Recognizing where the flowers and fruit develop on the different types of tree fruits is important and will determine how the different species are pruned and trained.
Tree fruit have two types of buds, terminal and lateral buds. Apples and pears flower and fruit primarily on terminal buds. A terminal, sometimes called the apical bud, is one located at the tip of a shoot. A lateral bud develops along the developing shoot at the base of the leaf blade.
The flower/fruit buds in apples and pears can be terminal on long shoots (greater than 4 inches) or more commonly on short shoots called spurs. A spur is a short shoot (4 inches or less) that only grows a very small amount each year. Spurs usually take 2 years to develop; that is, in the first year the bud is formed as either a lateral or terminal bud. If the bud is terminal, it may flower the next year or it may not. Lateral buds formed the first year may produce a flower, but the fruit that develops is small and of poor quality. More often, the lateral bud may thicken and grow only a small amount and develop as a spur, which may flower in the subsequent years.
The spur and terminal flower buds can have both vegetative and flower components. The buds usually produce about five to eight flowers and a similar number of leaves. Occasionally, a new vegetative shoot will develop after the flowers set fruit.
Pruning and training as described below will affect the amount and type of buds formed by apples and pears. Trees that are very vigorous, whether due to pruning or overfertilization, form fewer flowers.