I'm considering building a raised garden bed using paving slabs that are about 600x600x20mm. I'm not sure about the best method to keep them in place. Should I set them in concrete, or make a wooden frame around them to prevent shifting? Plus, has anyone else tried this?
2 Answers
Yes, those are the square concrete slabs you're thinking of! I’ve seen people use them half buried to create shallow beds. If they’re mostly underground, they tend to stay put better. Just a tip: make sure the ground is stable so they don’t shift over time!
I've watched folks build raised beds with these slabs, but there are some things to watch out for. If you live in a cold area, the freezing could crack the slabs because of the expansion in the soil. Another issue is moisture—if the slabs aren’t treated, they can wick moisture out of the soil. Some people use angle iron or wood to frame them, which can make a nice edge for the garden and gives you a spot to sit while you’re tending to your plants.
So it’s really the freezing of soil that cracks them, right? That makes sense!
I see your point! It sounds like that could definitely help keep them steady.