Flowering crabapple “Molten Lava” trained along a fence at Lake County Nursery in Perry, Ohio.

This year, the Philadelphia Flower Show’s theme was “Springtime in Paris,” and everything was very French. To my mind, “French” means fine wines, fabulous food and outstanding gardens. I wasn’t disappointed.

With the strains of “La Vie en Rose” playing in the background, I wandered the displays wishing that each one of them was my garden. My favorite was “Le Jardin de Toit du Chef” or more simply The Chef’s Rooftop Garden. It was conceived and brought to life by Stoney Bank Nurseries of Glen Mills, Pa.

Paris, like so many large cities, lacks space for traditional gardens, so rooftop and small space gardening are a way of life. Green roofs and container gardens are the most common forms, but in this chef’s garden, there were fruit trees, too. How do you do that?

They used a very old method known as “espalier,” which actually comes from the Italian word spalliera, meaning “something to rest the shoulder (spalla) against.”

Espalier can be grown flat in rows, pruned into hedges, trained on a trellis or shaped like a candelabra, fan, diamond and other shapes. The difference between espalier and topiary is that the espalier shape is skeletal and topiary provides a silhouette.

Espalier allows you to plant so that everything is flat or two-dimensional, taking up less space than a tree would occupy in the garden. It is commonly used to train grapevines along wires to make grape harvesting easy. This formal method of training trees and shrubs lets you reach the fruit without becoming an acrobat on a ladder.

Espaliered trees can be trained against a wall or into living fences. Training one low to the ground lets a person with limited mobility to work and harvest from the tree. Because most fruit trees require applications of pesticides, the height and shape of the tree(s) reduces the spray needed because you can make better contact with the leaves and fruit. Because you can care for your plants better, the yield is usually improved, too.

If you aren’t growing fruit, you can still train other woody ornamentals such as flowering crabapples (Malus sp.), flowering cherry (Prunus sp.), forsythia, Eastern redbud (Cercis canandensis), Magnolia ‘Little Gem’ and more.

The ideal location for planting receives six to eight hours of full sun a day and has moist, organic rich soil. Design the shape of your tree on paper before you start digging and drilling. You can place it against a masonry or brick wall. Use a masonry bit, drill holes evenly spaced along each line or row, usually 1 1/2 to 2 feet apart. Insert 2-inch lag shields (small metal cylinders with threading) into the holes, then screw in large eyebolts, approximately 8 inches long until the shield is flush with the wall. The eyebolts should protrude about half way out, allowing for good circulation between the wall and the tree. Run 16-gauge wire through the eyebolts, securing tightly at the end of the run.

Loosening the roots, plant your tree at the same height it was in the container or the burlap. There is a part of the tree called a “trunk flare.” It is at the bottom of the trunk,where it widens at the base. If the flare is not visible and is buried too deep, the tree will eventually die. After planting, water well and regularly, especially if you have planted under a roof overhang. In that case, dedicated irrigation is best for the plant.

While fall planting is desirable, you can plant in the spring. Tie off the desired branches to your pattern with nursery tape or some other soft tie so you don’t damage the plant. If you are planting fruit-bearing trees and shrubs, wait until after the fruit is set before doing any trimming at all. ALWAYS use sharpened pruners and disinfect between cuts between trees using a 10 parts-to-1 water-to-bleach solution to prevent disease transmission. The first cut is always the deepest, to paraphrase a song. Cut the tree leader or main stem about 2 to 3 inches above where you want the branching out to begin on the tree. Most people gasp when you tell them that, but if you want to train your tree, this is how you begin. This will force horizontal growth that you can start to train on your wires.

Decide which branches are best for tying off, usually the most flexible ones, then cut off the rest. This is done in the summer while the tree is actively growing. If you are using a non-fruit-bearing tree, continue to prune excess growth until the end of July, allowing the latest growth to harden off before winter. If you don’t have a wall, use a fence using turnbuckles to tighten up the wire.

It can take a few years to get your espalier trained into just the right shape, then maintenance continues as long as the plant grows. In a hurry? Local nurseries often carry trees that are already trained.

In these days of high food prices, worries about pesticides and much smaller yards, espalier is an ideal choice for the homeowner/gardener.