Nothing turns a city rooftop into a verdant paradise so much as an orchard of potted fruit trees, especially when they are in blossom, buzzing with pollinating bees, or dripping with fruit. But even if you have a tiny balcony, it's really worth including a fruit tree. Whether it's a single pear tree or a line of fan-trained peaches, apricots, plums, and espaliered apple trees edging a terrace, fruit trees bring a structure and a delicious sense of maturity to a balcony or roof garden.
(On just a quarter-acre of land, you can produce fresh, organic food for a family of four—year-round. Rodale's The Backyard Homestead shows you how; get your copy today.)
Which Tree to Choose?
Fruit trees are good in pots as long as they are grown on a dwarfing rootstock—any specialist supplier can help you select the right one for your balcony if you are unsure.
Always check with suppliers to see if you need more than one tree to ensure good pollination. Some fruit trees, such as cherries, apricots, and peaches, are self-fertile, so you will get fruit with only one tree; others, such as apples and pears, need a partner nearby to ensure pollination. If you have room for only one apple or pear tree, a "family" tree, in which three varieties have been grafted onto one rootstock, is ideal.
How to plant and grow fruit trees
You can grow fruit trees in a pot that is at least 1 foot in diameter and 1 foot deep. Galvanized dustbins are ideal, look surprisingly elegant, and can be picked up cheaply from hardware stores. Heavier options include halved wooden barrels or terracotta pots, while for super-lightweight versions consider plastic planters or rubber Tubtrugs. All will need drainage holes drilled into the base if they don't already have them and also should be tied to some sort of support, as a fruit tree in full leaf can really catch the wind. Since fruit trees will live for many years, it's best to plant them in a soil-based potting mix that releases nutrients slowly. Place the trees in a sunny spot to get a really good, sweet crop.
Feed potted fruit trees every two weeks from blossom time to mid-autumn with a high-potash feed such as liquid seaweed and keep them well watered. It's a good idea to mulch the surface of the soil (with shingle or cocoa shells, for example) to keep moisture in. The traditional time to plant fruit trees is in the dormant season from mid-fall to early spring, though you can pick up potted trees all year round. The pruning required varies depending on the form and type of fruit tree—it's worth buying from a specialist supplier who will provide detailed instructions.