In about four to five years, the linden canopy will form a solid roof. In the meantime, you could consider a temporary planting of vines, such as clematis, to provide additional coverage while the canopy fills in. And, if you like, the hazel frame can gradually be cut away as the branches grow stronger.
Maintenance is straightforward: two prunings a year to shape and train the canopy, once in spring and again in fall. Though regular waterings are important when the trees are young, they don't need to be fertilized and are not more prone to disease.
If you don't want to tackle (or lack space for) a living arbour, you can easily create cozy, shady nooks for garden seats from willow. Plant long, straight willow whips in a semi-circle about 30 centimetres apart and lash them together at the top like a teepee. The willow will take root and leaf out. Canadian Gardening's horticultural editor, Anne Marie Van Nest, recommends choosing varieties of Salix viminalis (grows three to six metres tall if left unpruned, Zone 4) or S. tiandra (grows up to 10 metres if left unpruned, Zone 5) for their straight, long stems and pleasing branch colour. Both are available from Bluestem Nursery (250/447-6363; www.bluestem.ca).
These are also good choices for creating living arbours:
• Ornamental pear (such as Pyrus calleryana ‘Chanticleer'),
• Upright hornbeam (Carpinus betulus ‘Fastigiata'), Zone 4
• Maple (such as Acer rubrum ‘Bowhall'), Zone 3
• Gingko (such as Ginkgo biloba ‘Fastigiata' or ‘Princeton Sentry'), Zone 4
• Honeylocust (such as Gleditsia triacanthos ‘Shademaster'), Zone 4
• Japanese tree lilac (Syringa reticulata ‘Ivory Silk'), Zone 3
• English oak (Quercus robur forma fastigiata), Zone 4
Brenda Dinnick & Assoc. 416/929-1495.