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.
All year round they offer something beneficial—from a beautiful winter silhouette to a froth of spring blossom, leafy shade, and shelter for other crops, and then finally they give up their sun-warmed fruits, all the sweeter for having been grown right there.
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. Either grow a traditional-shaped tree or experiment with some of the lovely trained shapes and grow them up against your wall—they’ll really benefit from the warmth the bricks retain from the sun’s heat and are often more productive than traditional bush- shaped trees.
The easiest form of fruit tree for even the tiniest of balconies is an upright cordon. These take up hardly any space since they grow as single upright stems, reaching about 6 ft. tall, with short, fruit-bearing side branches that need minimal pruning in summer. U-shaped cordons are just as attractive, with a pair of upright stems studded with fruit, while “double-U” cordons are perhaps the most ornamental of all.
If you have a lot of wall space around your terrace or balcony, fan-trained trees look particularly lovely, spreading out their branches against the wall and soaking up the heat absorbed by the building to produce the most delectable fruit. (Allow about 6 ft. of horizontal wall space per tree.) Figs, peaches, apricots, cherries, and plums all grow happily as fans. Other fruits such as apples and pears can be pruned as espaliers, with horizontal branches coming off a vertical stem, or even as double-U cordons.
For both fans and espaliers, simply fix parallel wires to the wall to tie the branches to, or use your railings as supports. You can train these trees yourself, but it’s much easier to buy them ready-trained. They may be considerably more expensive, but since you can expect your potted tree to provide you with a harvest for many years, it’s worth investing a little more at the start.
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.
The top 6 fruit trees for an orchard balcony
The quintessential orchard fruit that can be grown as a bush on dwarfing rootstock, or as an espalier, U-shaped cordon, or double U. Delectable dessert varieties include ‘Gala,’ ‘Fuji,’ and ‘Honeycrisp,’ all of which will pollinate each other. Or try ‘Jonagold,’ ‘Pink Lady,’ ‘Ashmeads Kernal,’ or ‘Cox.’ Good cooking varieties include ‘Gordon,’ ‘Liberty,’ and ‘Sierra Beauty.’ Or choose a “family” tree, perfect for small spaces since it combines three varieties on one tree.
A ripe pear is a wonderful thing, but since they flower early, their crops can be damaged by late frosts. To be on the safe side, cover the branches with fleece if they’re in blossom when a frost is forecast. Pears can be grown as a bush on dwarfing rootstock, or as a cordon, espalier, U-shaped cordon, or double U. Good dessert varieties include ‘Bartlett,’ ‘Moonglow,’ and ‘Doyenne du Comice’. As with apples, it’s also worth looking out for “family” trees that have had three varieties grafted onto one rootstock.
Modern cherries are self-fertile, so you only need one tree to ensure a good crop. If you can keep the birds off, that is; netting may be a necessary defence as the fruit ripens. Expect beautiful blossom and lots of fruit when the tree is established. Grow cherries as a bush on dwarfing rootstock, or as a fan against a warm wall. Good varieties include ‘Lapins’ and ‘Stella.’ If you have a shady, north-facing wall, a morello or acid cherry will thrive as a fan, producing tart cherries that are excellent when cooked.
These accommodating trees deliver heavy crops with very little asked from you in return. Pruning is minimal (and certainly should never be attempted except in summer to avoid fungal infection) and most are self-fertile. The only thing they demand is that the developing fruits are thinned out, otherwise plum trees tend to produce far too many plums one year, followed by nothing the next. Thin plums in mid-summer so they are about 2 in. apart. Either grow plums as a bush on dwarfing rootstock or as a fan. Try greengages for their unique buttery texture and sweetness.
Peaches and Apricots
Once you have tasted your first ripe peach or apricot straight from your own tree, there’s no going back. Such experiences have to be repeated, and you’ll go to no end of trouble to do so. As with all container fruit trees, make sure you buy a tree with the suitable dwarfing rootstock. A good dwarf peach is ‘Bonanza,’ or try ‘Pixzee’ or ‘Pixie-cot’ for a dwarf apricot. All these can be grown as free-standing trees in pots and need little pruning; alternatively they can be grown as fans.
Both peaches and apricots are hardy when dormant over winter, but since they blossom early in the spring, the flowers are susceptible to frost damage. Bring the tree inside when in blossom if frost is forecast or cover with horticultural fleece if it is trained against a wall. Although self-fertile, both trees can benefit from a bit of help with pollination to ensure you get a good crop—when the flowers are open, dab the pollen gently with a soft brush and rub it onto the surrounding flower. Peach leaf curl is a nasty fungal disease, so if you can find a dwarf variety that claims resistance to this disease, buy it.
How to plant and grow fruit trees
You can grow fruit trees in a pot that is at least 1 ft. in diameter and 1 ft. deep. Galvanized dustbins are ideal, look surprisingly elegant, and can be picked up from hardware stores cheaply. 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 are not already there, 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 which 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 midfall 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 because they will provide detailed instructions.
Highly sustainable Balcony Garden
Your sky-high city farm may be small, but that doesn’t mean it can’t be sustainable. Whether you’re capturing rainwater, turning your kitchen scraps into fertile potting mix, or even keeping bees, you can create your own little eco haven in the sky, a selfsustaining Eden that not only puts food on the table but helps the wider environment too.
Be a worm farmer
If you have a balcony, you probably have space for a wormery, and that means you can be turning your carrot peelings and apple cores into lovely food for your growing plants.
Wormeries are carefully designed worm farms in which layers of wriggly, red brandling worms—different from the ones you usually see in garden soil—munch through your kitchen waste and produce both rich potting mix and nutritious liquid feed that you can dilute (one part worm liquid to 10 parts water) and feed to your plants.
Wormeries take up less space than potting mix bins, so they are a better choice for balcony gardeners. The waste is also broken down at a much faster rate than in a traditional potting mix bin and they don’t need to be placed on earth, unlike potting mix bins, since any liquid that collects in them can be drained off with a handy tap and then fed to your plants. Also, again unlike potting mix bins, wormeries can digest both raw and cooked vegetables, bread, cake, pasta, and plenty of other food waste— though not meat and fish scraps—so they will really reduce the weight of your kitchen garbage can. They’ll also cut down on your recycling, since worms love a third of their food to be shredded cardboard or paper: the perfect use for all that packaging.
As this worm potting mix is very rich, all that you need is a handful or two of it mixed in with your regular potting mix when you are planting something. It’s wonderful as a mulch, added as a layer about 2 in. thick around hungry and thirsty plants. It can also be used to freshen up potting mix when you’re taking out crops and replacing them with new ones.
By saving rainwater in rain barrels and using it on your plants you’re reducing the pressure not only on your city’s storm drains – a real problem for cities such as New York and London – but also on yourself: it’s much easier to fill a watering can from a rain barrel on the balcony than to drag a hose through the house from the bathroom tap.
It is easy to connect a rain barrel to your downspout, and kits are readily available which include fittings to the downspout. You may need a plumber to help you if your downspout is metal, but if it’s plastic you can cut into it yourself with a hacksaw. Obviously, if you live in an apartment house or don’t own your building, you would have to check with your building owner before altering the pipe in any way.
If you’re worried about the weight of a rain barrel on your balcony or terrace, keep in mind that 1 quart of water weighs 2½ lb.