Garden Structures: The Pergola
Add architectural interest to your garden or backyard with a pergola — the perfect spot under which to set a dining table or catch some shade while reading a book. Dress up a pergola with flowering creeping vines for a fragrant, lush backdrop or a stunning garden focal point.
A pergola typically refers to a passage or covered walkway formed by two rows of upright pillars supporting horizontal beams or joists as the roof. A pergola’s roof is often flat and its joists can project beyond the support posts, creating an architecturally pleasing structure that’s also ideal for climbing vines or flowers to attach themselves to.
Although an arbor usually refers to an arch-shaped wooden or metal structure often the same size as a typical doorway, the terms “arbor” and “pergola” are often used to refer to the same type of structure.
Create a seating area by placing a simple arbor or pergola over a garden bench for a shady retreat. Pergolas can be bought ready-made and assembled on site, or for the DIY enthusiast, constructed from scratch. Either way, begin by planning the location for your pergola, taking into consideration where the sun is during the day, the pergola’s view from the house and whether the pergola is meant to be a focal point in the garden or simply a corner accent.
If space permits, think about creating extra outdoor living space by adding a pergola to your front yard. Or use one as a gate in your front yard’s entryway for a wonderful, welcoming touch.
A poolside deck is another great location for a pergola. A pair of comfortable lounge chairs perched below a shady vined roof is a welcome retreat on a warm summer day. Or use the pergola as shelter for a wet bar or barbecuing area.
A pergola can also visually extend the roof of an adjacent shed or porch, creating a perfect spot for an outdoor dining room.
The most common pergola material is wood: teak and cedar are both good choices. While teak is more expensive than cedar, both are very hardy, weather to a beautiful silvery-gray colour and will last for years. Pressure-treated lumber is another widely used material which also weathers well.
Metal is another option for pergola construction, although it is more often used for smaller structures. If purchasing a metal arbour or pergola, make sure that the metal is rust-proofed and won’t require touch-ups every year.
About pressure treated wood
The three chemicals used in the treating process of “CCA” pressure treated wood (widely found at home-supply stores) are copper, which acts as a fungicide; arsenic, which is effective against insects and animals like beavers; and chromium, used to keep the other two chemicals from leeching from the wood.
The chemicals are applied at high pressure so they can reach as far into the wood as possible. The reaction of the elements with each other and with the wood minimizes the amount of chemicals that might leech out of the material. Arsenic has lately become more of a safety concern to consumers, so you may want to consider cedar as a good natural alternative.