Patio raised bed construction

Frank O\’Connell asked 11 years ago

I have constructed a raised bed using concrete blocks about 500mm high, with sand/cement mix as an external finish. Do I need to line the inside of this wall before filling with soil to avoid later damp/green algal growth on the wall exterior and if so, what should I use?

1 Answers

Gerry Daly Staff answered 3 years ago
It is very likley that water will leak through and could well give rise to algal growth, but even if you line the bed with polythene, it will be wet unless the whole thing is sealed as a tank, which sounds like a lot of bother.

Nutrients could well leak through too causing a white efflorescence on the wall. If you are concerned about this, and algal growth, perhaps a power wash every so often might tidy it.