Who doesn’t love the idea of a long narrow table, out of doors, gingham tablecloth, carafes of wine, delicious food and friends and family under a curtain of roses and flowering vines? Ok it is a cliché and repeated endlessly in films, especially those with a mafia theme, but really you can’t go far wrong with a pergola. They date back to the ancient Romans (who probably copied them from the Greeks, who in turn got the idea from the Persians). Pergolas fulfill a number of roles; they are really decorative, add a really nice vertical element to a garden, they provide support for climbing plants and make a great spot to put a table under!
You can make a pergola as big or small as you like; it can be more like an arch, or it can be used to link one part of the garden to another, or to create an outdoor room. Some people grow them purely to show off a few particularly good roses or clematis.
It is really quite easy to make a pergola, but very important to do the job properly and make it sturdy. There is nothing worse than seeing a windswept and bockety looking bodge job listing to one side after the first puff of wind. You also don’t want to be sued when a litigious acquaintance who has a crossbeam land on their head at your Italian-style al fresco lunch party.
A DIY job will be hard work but deeply satisfying. You can do it over a couple of weekends or a bank holiday. It will only take two half days of work, the rest of the time is to allow the concrete you set your posts in to set (or go off as we say in builder’s parlance).
How to do it:
Decide how big you want your pergola to be and choose your material. If you want to use brick uprights, which look great, use a professional, unless you happen to be super handy and good at bricklaying. Brick uprights make a much sturdier and long lasting pergola but they cost more.
If doing it yourself use pressure treated softwood – if it is not treated it will rot quickly – or a hardwood.
You will need:
- For the uprights – pairs of wooden posts, 85mm x 85mm x 3m (3.3in x 3.3in x 9.8ft) – you will need a post about every 1.5m (6ft) to make the pergola sturdy.
- As many wooden cross members (for the roof or top) as you like, 33mm x 33mm x 1.8m (1.3in x 1.3in x 5.9ft)
- Wooden beams to attach the crossbeams to 45mm x 95mm x 3m (1.7in x 3.7in x 9.8ft)
- Bolts to support the frame
- Stainless steel screws, countersunk
- Sand and cement or concrete mix
- A good electric screwdriver
- An electric drill
- A spirit level
- Measuring tape
- A plumb line (or piece of long string if stuck)
- A reasonably competent friend or family member to act as builder’s mate
- Choose as level a piece of ground as you can. If you are putting your pergola on a patio it will probably be level already which makes the job easier. You will have to lift up slabs where the uprights are to go.
- Using your mate, measure carefully where the uprights are to go and mark them out. Make sure they are arranged so they’re square with each another. The posts should also be far enough apart to allow a couple of people to walk side by side through the pergola when it is heavy with foliage and flowers and even wider if you want to fit a table underneath.
- Dig holes for all posts; these should be 30cm x 30cm (1ft x 1ft) wide and 60cm (2ft) deep.
- Prop a post upright in one of the holes, and then do the same for its neighbour.
- Put a cross member on top of these two posts, then place a spirit level on top to check they’re level; if they’re not, infill or backfill the holes as necessary until they are.
- Repeat this with the remaining uprights until all are level.
- Make a good stiff mix of concrete, using just enough water to bind the ingredients together but not make it sloppy. Have your mate hold the post steady as the concrete is poured into the hole.
- Compact the mixture around the post with a piece of wood, taking care not to move the post from its position.
- Make sure that the post is level using a plumb line. Repeat these procedures with the remaining posts.
- Leave the pillars propped in position so they don’t slide or list – use bricks or garden chairs or batons.
- If you have got the uprights in straight and they are solid you have done all the hard work. The rest of the job is pretty straightforward.
- Join all the posts at the sides with your cross members and bolt them into position – leave 30cm (1ft) or so hanging proud either side.
- To help you position the cross beams across the roof of the pergola and screw into position.
- If you want you can paint the pergola or stain it. You can also put trellis along the sides if you want it to be more closed. Otherwise just fix wires or plant supports where you need them.
When planting your pergola remember to dig your holes a good 30cm or 1ft away from the concrete around the upright posts and to dig in some compost. Don’t worry if it looks a bit odd don’t worry, you can train the plant up the pergola posts using wires or bamboos.
Plants to suitable to grow over a pergola:
Don’t be tempted to plant a solanum of any kind on your pergola, they are tempting as they grow so quickly, but are far too vigorous and unruly and you will deeply regret it in two years at most.
Actinidia deliciosa ‘Hayward’
Lonicera japonica ‘Halliana’
Rosa ‘perle d’azur’
Vitis coignetiae vinifera ‘Purpurea’