Sometimes the simplest ideas are the loveliest. Take this arbour, for instance, whose quiet elegance caught my eye while I was on a Toronto garden tour a couple of years ago. Although the garden itself was large and quite grand, its landscape architect, Brenda Dinnick, didn't take the usual route by designing an arbour built from traditional materials to cover the outdoor seating area. Instead she opted for a light and airy living arbour, whose leafy canopy will fill in over time and change with the seasons. Once the arbour's yellow autumn leaves have fallen, the homeowners will have the pleasure of looking out at and through the arbour's interesting, intertwined branches, perhaps at times dusted with winter snow, to the garden beyond.
An added bonus: a living arbour is easier and less expensive to create than a wooden structure, for example, though it does require regular maintenance. Dinnick worked with Peter Lawrie of O.J. Muller Landscape Contractors, who made and maintains the arbour, but with the help of a friend or two, you can tackle the job yourself. Here are a few pointers.
To create the arbour's boundaries, Dinnick planted four littleleaf linden saplings (Tilia cordata, Zone 3), spacing them about three metres apart. (The spacing, and number of trees used, depends on the size of your seating area underneath. Err on the side of generosity, allowing for plenty of room to move chairs.) Willowy, rather than stocky saplings (you want them to be flexible) of up to three metres tall are ideal. The arbour could also be planted as a focal point to arch over a pathway.
Dinnick chose these lindens for their long, straight trunks and dense canopy of heart-shaped leaves (there are also small, pale yellow, delightfully fragrant flowers in summer-but be aware that they do attract bees). The saplings are underplanted with periwinkle (among which you could tuck in some spring, summer and autumn-flowering bulbs, such as allium, martagon lilies and autumn crocus-Colchicum autumnale).
Dinnick then devised a frame for training the arbour's canopy. This is basically a grid made from long, straight, harvested hazel suckers tied together with wire. However, you could use any kind of branch for the frame, even bamboo, provided that they're long, straight and flexible, and their colour blends in with the saplings. The grid is assembled as you go along, with the lindens' branches woven through and tied into the frame with sisal cord. Dinnick recommends sisal because it biodegrades after about two years, by which time the lindens' branches will be able to hold each other up in the direction you want them to grow. Do not use wire or any type of poly cord; it will girdle the tender living wood.