The Surprising Things Trees Can Do For Your Garden

In honour of Earth Day, we look at a few of the magic tricks trees can perform in your garden.

MONEY WELL SPENT | In the landscape of memory, trees define the countryside. As the most prominent and long-lived of all vegetation (think giant sequoia), they are the one green symbol guaranteed to represent place. Mention Italy and Italian cypress come to mind. Images of southern France always include olive trees. The English landscape, that great affectation, is symbolized by large-scale deciduous varieties planted in “clumps” (by Capability Brown) that look from a distance like a single stylized tree. In the Pacific Northwest, iconic evergreens—Douglas fir, Western red cedar and hemlock—colour much of the landscape black-green, a situation that both pleases and perturbs me.

I have a love/hate relationship with these vertical giants. I love them unequivocally in the wild, but in the city, my feelings are mixed. They are messy for one thing, too thirsty for another. They can rob a tiny garden of sunlight, and turn otherwise amiable people in to axe murders. How many times have I read about someone topping or chopping down a neighbour’s evergreen—without asking permission—to improve his or her own view or to capture extra sunlight?

When clients ask me to preserve the large fir, cedar or hemlock on their site, I always try to do it. Rarely, however, do I choose to install these trees, and when I do, it’s usually to create a backdrop or a screen on a larger property where their height and mass can be viewed from a distance.

Most of the trees I specify are quicker growing deciduous varieties. I select them for their height and shape when fully grown; for their novel bark or branching or leaves (the majority of deciduous flowers are short-lived and uneventful); and for the work I need them to do.

What Trees Can Do For You

One of the things I love about deciduous trees is what they do in the sunlight. The leaves and branches of Victoria’s Garry oak, for example, cast a magical dappled light that is unique in Canada. The fat, flat leaves of the Sorbus aria ‘Lutescens’ (whitebeam) outside my studio window are grey-green on one side, ash white on the other. On sunny, breezy days, they shimmer the way waves do when they’re caught in a shaft of moonlight.

If you want to illuminate a corner of your garden where the sun doesn’t shine, a shock of coloured leaves will do it. I’ve used the acid yellow foliage of Robinia pseudoacacia ‘Frisia’ (black locust) to light a dark spot, but I wouldn’t recommend putting a lot of these trees in a small space; the overall effect would be off putting, too many trees screaming “Hey, look at me!”

I once had a client from Hong Kong who collected deciduous trees the way keen plantsmen accumulate perennials. No matter what quantity I specified, he asked me to squeeze in more. “I like trees,” he told me, “because they actually relax me.” Botanists might back him on that: Trees are the earth’s lungs, absorbing carbon dioxide and giving off oxygen; it’s not much of a stretch to think of siting a house in the woods as a form of oxygen therapy.

This may sound illogical, but if you want to make you garden feel larger, plant more trees, not fewer. The more trees you have, the easier it is to create the layered look found in nature.  Planting in layers contributes to the sense that a garden goes on indefinitely. It also means you are going to get more shadow play, which makes it more difficult to gauge boundaries; believe it or not so does leaf size. If you want to exaggerate the depth of a property, plant larger-leafed trees close to the house and smaller leafed ones in the distance, and use more of fewer species, but clump them together the way they would grow in the wild (like the vine maples pictured here).

How To Save Money When Buying A Tree

Trees are sold one of two ways: in pots or balled and burlapped (known as B and B). The price of a tree can jump substantially once it has been removed from a pot and and wrapped in burlap, a process that requires extra labor that can be reflected in the cost. It makes good sense to find the largest specimen in a pot rather than the smallest one in burlap. Once the smaller tree is in the ground it will make up for any size differential quickly.—Ron Rule

Ron Rule is a well-known residential garden designer in Vancouver. He is the founder and head of the Certificate In Garden Design program at the University of B.C.

Photo: vine maples, IStock