How to build a pergola
Posted: March 23, 2017
Categories: Garden Design
A pergola is a great way to support climbing and rambling plants. Pick the right plant (think of wisteria, honeysuckle and jasmine) and you could be walking through a tunnel of perfume as you stroll around the garden. Correctly positioned, a pergola can frame a particular view of the garden. Every garden usually needs to make full use of all available space – and that includes the vertical.
The trick to getting a pergola to last a long time is to use pressure treated wood - that includes uprights and cross beams. When planning you also need to ensure you have enough space to walk through the pergola without stooping or, worse still, banging your head. A clear seven feet usually does the trick. What this means, however, is that the uprights need to be sunk and concreted into the ground to a depth of three feet. It seems deep, especially when you are digging the holes, but the weight of the post plus the weight of the cross beams plus the weight of fully grown wisteria is considerable. And you really don't want to be repairing a pergola once it is erected. Do it once and do it right first time.
Uprights have to be just that – upright. Get help and always use a spirit level. Sink the posts deep and support them whilst the concrete is setting (some ready-mix packs say this can be as little as five minutes after mixing but allow a few hours or even overnight to ensure the concrete is fully cured or 'gone off'). Measure, and measure again, before any cutting. Place and fix the cross beams once all uprights are set solid.
Ready-made kits are available and it does make the job easier. All timber is cut to size and is treated with a 15-year guarantee against rot.
Once up, it is time to plant – remember the immediate area around the posts is concrete so any climbers will need to be leaned into the upright and tied in. But before long, anything you plant will be romping away to help create a stunning focal point or passageway in your garden.