If you're like most Canadians, you consume apples more often than any other fruit. And with the availability of dwarf trees and cultivars that are very hardy - some to Zone 1 - many Canadians can grow their own.
Buy your trees from a local nursery or from one in a similar climate zone so you'll have specimens suited to your growing conditions. Two different apple varieties that flower at the same time are needed for cross-pollination; a crabapple will also do the job. Commercially grown trees have two parts: The root portion - or rootstock - determines the ultimate size of the tree and the time until the tree reaches fruit-bearing age, as well as influences its hardiness and productivity. Grafted onto the rootstock is the specific variety, which determines the colour, taste, quality, season of maturity and disease resistance of the fruit.
Choose a site in full sun that has good drainage and air circulation, and is protected from strong winds. Avoid low-lying areas or frost pockets, where cold air settles. A slight slope is ideal so cold air can flow away from the trees.
When planting, dig a hole for the tree twice as deep and wide as the root ball. Fill the bottom with a mix of soil and compost so the hole becomes as deep as the root ball. Don't add any fertilizer. Position the tree so the graft union (the swollen area several centimetres above the roots) is five to 10 centimetres above the soil line. Then fill in with soil, pressing it down gently but firmly; water the tree well. Spread a two-centimetre layer of compost in a one-metre circle around the trunk and sprinkle with organic fertilizer. Cover with 10 centimetres of wood chips, keeping the chips away from the trunk of the tree. This will help conserve moisture and keep weeds and grass from competing with the tree. Dwarf specimens should be staked permanently, while full-size ones benefit from being staked for the first few years.
During the growing season, make sure the trees have at least 2.5 centimetres of water each week (whether from rainfall or irrigation), from May through August. Pull out any weeds that grow through the mulch. Each spring, pull back the mulch, spread a 2.5-centimetre-thick layer of compost over the soil under the canopy and dig in organic fertilizer before replacing the mulch.
Some years, trees will set too much fruit, which can result in small apples, a poor crop the following year and a heavy weight that could damage branches. When fruits are marble-sized, thin to one fruit per cluster; for large apples of optimal quality and size, thin to 20 centimetres between fruits on a branch.
If you buy a one-year-old whip without branches, prune back to 1.2 metres to encourage side limbs. For a two-year-old branched tree, thin side limbs to 20 centimetres apart. The second year, remove main lateral ones that are too crowded and any that cross other ones, and prune out dead or weak growth. In subsequent years, prune to develop an open tree where all branches receive light and good air circulation.