HOW TO RENDER RAISED BEDS (SUCCESSFULLY)
Here’s how I rendered the raised beds in my garden, plus how they’re holding up after their first winter.
(Post contains affiliate links)
When I was searching for a tutorial for how to render raised beds, the only thing I actually found online were horror stories and people saying not to do it. For lots of people, the render cracks and flakes off super quickly, even when it’s done by the professionals. The advice from landscapers online all contradicts each other, and there’s just threads and threads of forums of people bickering about it.
I had someone booked to both build the beds and then render them for my courtyard garden makeover, hoping for the best. But it was when there was a real shortage in tradespeople, and when the renderer cancelled, I thought I may as well give it a go myself and save a bit of money. Given it might all just fall off anyway whoever did it, I thought it was a calculated risk.
It sounds like the main problem is having rendered walls with flat tops, as the water can sit on it and then seep into the render and cause it to crack. But, I really didn’t want to have a coping stone on top of mine - absolutely not the vibe I was going for.
I got a little bit of advice from my builder (the lovely Chris at All in One Design), and went for a belts-and-brace approach to try and make sure they lasted for as long as possible. What I did might have been overkill, I have no idea, but they’ve lasted the first winter with not a crack or damp patches in sight, so regardless, it’s worked.
I’m not going to focus on the technique of applying the render in this little tutorial as you can probably find that better elsewhere anyway, instead I’m just going to let you know the steps I took as part of my rendered walls, so you can do it yourself or ask your landscaper to try.
Use an SBR
Once the raised beds were built, I used this Bostik Cementone SBR from Amazon and painted on a coat on the inside, outside and top. This is like a primer and a bonding agent.
2. Apply a scratch coat
After I’d stuck some render corner beads across all of the beds, I applied a scratch coat of render. We used this Tarmac One coat Ready mixed Render from B&Q mostly because you don’t have to worry about mixing up quantities. It was pretty good actually!
3. Push fibreglass mesh into the render
Once I had a first coat of render on, I pushed in this Render Fibreglass Mesh from Amazon. With this, you don’t need to do the actual scratching of the scratch coat, and it helps with strength and preventing cracking. I let this layer dry for a day or two, though you’re probably better waiting a bit longer.
4. Add your second coat of render
Next, I applied a second coat of render. This was the one I had to get looking good and smooth, so I spent my time on this one.
5. Use a waterproof primer before painting
I left this second coat to dry for about a week, more just because I was busy more than anything. Before painting, I used Zinsser’s Bullseye 123 Primer from Amazon to give the beds an extra waterproof layer.
6. Use an exterior paint
After that, I painted the raised beds with 2-3 coats of COAT’s exterior paint in Pampas (supplied as part of a previous paid collaboration).
7. Use an exterior varnish to finish
Last step, I finished off with my go-to-for-everything Polyvine Decorators Varnish in Dead Flat finish from Amazon, just applied with a paintbrush and roller. I’m probably going to reapply this every year, and only re-paint when I need to. The colour still looks fresh after a pretty grim winter, so I’m really happy with how durable they’ve turned out.
As I said, this is just my experience of rendering raised beds and doesn’t go into all the detail on the application and sanding I did in between, but given I couldn’t find a single useful article online that was honest about the risks of rendered beds or had a successful example of one done, I thought it was worth sharing on the blog!
Let me know if you try this out and if it works for you , or if you have any questions, by dropping a comment below.