How to fit trellis to a fence

Video by Wickes. This guide is based on the video "How to Fix Trellis onto a Fence Panel with Wickes" from the official Wickes YouTube channel, which walks through the tools and fixings needed to attach trellis to an existing fence panel. Worth a watch before you start — the section on using timber battens to hold the trellis away from the fence face is the detail most people skip.

1. Pick the right trellis for the job

Diamond-pattern trellis and square-pattern trellis are the two main options you will find at most UK builders merchants and garden centres. Square pattern gives plants a wider grip point; diamond tends to look a bit more traditional and suits cottage-style gardens. Both come in treated timber or plastic — for most East Kent gardens, treated timber gives a more natural finish and takes wood stain well if you want to match the existing fence.

Check the trellis dimensions against the space you have. Standard panels run at 1.83 m wide and anything from 30 cm to 90 cm tall. If you are topping a fence, measure the fence width precisely — a panel that overhangs or falls short by 10 cm looks untidy. To be fair, a small amount of cut-down is fine as long as you sand the sawn edges and apply end-grain preservative before fixing.

2. Gather your tools and fixings

You will need a cordless drill-driver, a tape measure, a spirit level, and some 38 mm or 50 mm galvanised screws — ordinary steel screws will rust through within a couple of years, especially if clematis or roses are holding moisture against the timber. Pick up a bag of galvanised or stainless screws; it is not worth saving 50p on the wrong type.

For fixings to a masonry wall, you will also need a masonry bit and wall plugs. If you are fitting to an existing fence panel, batten offcuts are useful — you screw the batten to the fence first, then attach the trellis to the batten. That gap between trellis and fence is important; without it, the fence panel rots faster and climbing plants cannot get behind the trellis properly.

3. Mark out and fix the support battens

Cut two lengths of 25 mm × 38 mm treated batten to match the height of your trellis panel. Hold each batten vertically against the fence at either edge of where the trellis will sit, check it is plumb with a spirit level, and mark the screw positions. Use at least three screws per batten — top, middle, and bottom — and sink them into the fence post or frame rather than just the panel itself where possible.

On a brick or block wall, use a 6 mm masonry bit, plug the holes, and drive 50 mm screws. Check the battens are sitting flush and level before you move on. A batten that is even slightly out of plumb will pull the trellis off-true and you will see it every time you look at the garden.

4. Offer up the trellis panel and check the fit

With a second pair of hands, hold the trellis panel up against the battens and check the fit. It should sit roughly centred on the battens and clear the fence surface by 25 mm or so. Mark the screw positions on the trellis frame where it meets each batten — aim for at least two fixings per batten, one near the top and one near the bottom of the trellis frame.

Mind you, some trellis panels are quite flimsy across their width if you are spanning a wide gap. If yours wobbles noticeably when held in place, add a central batten as well. The extra fixing point makes a real difference once climbing plants start to add weight in summer.

5. Fix the trellis to the battens

Drill a small pilot hole through the trellis frame at each mark — this stops the timber splitting, especially near the ends. Then drive your galvanised screws through the trellis and into the batten behind. Keep the screw heads snug but do not overtighten; trellis frames are not thick timber and it is easy to crack them if you crank the driver up to full torque.

Step back and check the panel looks straight before the last couple of screws go in. It is easy to adjust at this stage, much harder once all the fixings are home. That said, small variations in the fence surface can make perfectly good trellis look slightly off — if the fence itself is not flat, there is only so much you can do.

6. Treat the timber and tie in your plants

If you have used untreated or bare-sawn sections, apply a coat of exterior wood preservative or fence paint with a brush before planting begins. Pay particular attention to end-grain cuts and any screw holes — moisture gets in fast through raw wood and shortens the life of the trellis significantly. Match the colour to the fence if you can; most fence paint ranges include a reasonable selection of browns and greens.

When planting climbers, set them at least 20 cm away from the fence base rather than directly underneath it — the fence casts a rain shadow, so plants right up against it can struggle for moisture. Tie new stems to the trellis loosely with soft garden twine, leaving room for the stem to thicken. Roses and wisteria in particular can seem delicate in the first year, but give them a season and they will find their own way.

When to call a handyman

Call Richard if the fence panels themselves are rotten or unstable — there is no point fitting trellis to something that will fall over in the next gale. Likewise, if you are fitting trellis to a high wall and need a scaffold tower or a decent set of ladders, it is worth getting someone in who has the right kit. Fixing into older brick with crumbling mortar also wants a bit of care around which type of wall plug to use and how deep to drill.