Ken Slingerland, tender fruit specialist with the Ontario Ministry of Agriculture and Food, advises against fertilizing peach or pear trees with nitrogen fertilizer any time during the planting year, as this could affect good root development and hardening-off. Early in the second and subsequent springs, apply a balanced fertilizer around the drip line of each tree, with about 40 grams of nitrogen for each year of growth. For example, a five-year-old tree needs 200 grams of 10-10-10 fertilizer in the spring. Neither peaches nor pears should ever be fertilized any later than the end of June, as this may compromise their winter hardiness.
Weed control is very important in the first few years after planting, as weeds compete with young fruit trees. Keep the area around the trees well mowed, and hand-pull grass and weeds close to the trunks. Straw mulch works well, but watch out for rodents.
Trees need at least three centimetres of water each week, whether through rainfall or irrigation. When watering, make sure to thoroughly soak the soil.
Patience is definitely a virtue when it comes to growing fruit trees. Around the third year after planting, peaches of eating quality will start to develop. Pears, however, take five or six years. Because fruit buds for the next year are established in late summer or fall, the amount of blossom and fruit set will often reflect the growing conditions of the previous summer.
Despite a number of fruitlets falling off, the result of a phenomenon called June drop, peach and pear trees generally set more fruit each year than they can support. Both species need to be hand-thinned beginning in mid-June, once fruits start to develop; otherwise fruits will never reach their full size and branches could snap off under the weight of too much fruit. For peaches, thin the fruit to about 15 centimetres apart on the branches. Pears should be thinned to about one fruit per spur (fruiting stem).
How to prune
Nursery trees should be pruned shortly after transplanting, says Ken Slingerland, tender fruit specialist with the Ontario Ministry of Agriculture and Food, with a central leader shape the most desirable. He suggests pruning the leader down to about one to 1.5 metres. Then remove all broken or weak side branches and shorten the rest, leaving about seven main ones, with the first side shoot branching from at least 25 centimetres below the top of the tree.
In the second and subsequent years, pears should be pruned in late winter or very early spring before bud break. For peaches, wait until the buds are swelling or close to bloom so that you can see what tissue is alive. For both peaches and pears, prune out anything that is dead, broken or weak. Also remove any strong, upwardly growing branches that are competing directly with the central leader. Then, eliminate any crossing over of side shoots by pruning out one of the overlapping branches. Finally, remove any side branches that are close to the ground or growing up from the roots.
Diseases and pests
Both peaches and pears are subject to a number of infestations. There will be considerably more disease and insect pressure if the trees are growing in close proximity to commercial plantings of fruit trees. As well, wet growing seasons increase susceptibility to diseases, while hot, dry weather is conducive to more pests.
Peaches: Oriental fruit moth (larvae bore into ripening fruit) and aphids; brown rot is the most common fungal disease, but peach leaf curl disease can eventually kill the tree if left uncontrolled.
Rabbits, deer and voles in particular all love to munch on newly planted fruit trees. Small animals can be deterred by either wrapping trunks with plastic tree guards or painting trunks with a mixture of latex paint and thiram fungicide (animals don't like the taste). Commercial formulations of thiram available for this use include Skoot and Rabbit Repell. Higher fencing may be necessary if deer are prevalent
Pears: Subject to a number of the same pests as apples, including coddling moth and oblique-banded leaf-roller. Soft-bodied insects, such as psylla and mites, sometimes feed on the tree, making it and the fruit quite unsightly. Pear scab can render the fruit inedible.
For peaches, dormant lime sulfur sprays help to reduce leaf curl; soap sprays control aphids; and sulfur sprays applied just before and after blossom and again when symptoms are noticed minimize brown rot, as will good sanitation around the tree (removing mouldy fruit, for example). For pears, a combination of sulfur sprays and leaf-litter cleanup in the fall help reduce pear scab; soap spray solutions keep pear psylla at bay; regularly removing dropped fruit reduces coddling moth numbers; and pruning infected areas prevents the spread of fire blight.