If you are planning on building your own raised beds then you have wondered if you can use decking boards for raised beds? well, let’s have a look and find out. Also while you are here you may find my really simple raised beds build guide useful.
Can you use decking boards for raised beds?
Yes, you can. And as you can see from the image above I commonly do use decking boards to make my raised beds.
So where does the confusion in relation to decking boards come from? Well as it turns out there is still some outdated information online telling you not to use decking boards for raised beds, so what gives?
Well the advice was sound at the time and still is in relation to old decking boards, what has changed is the decking boards themselves. Mainly I am talking about the treatments the boards receive in order to make them more resistant to the weather.
It used to be that all pressure treated timber had lots of pretty nasty stuff in it. Stuff like arsenic and high levels of chromium.
This has all changed now and the pressure-treating process now uses a copper-based treatment. The older process of using arsenic has been outright banned so you don’t have to worry about buying wood that has been treated in that way by accident.
What this means is that any new decking board is safe to use for raised beds but won’t last as long as old decking boards used to. The new treatment, while safer, doesn’t provide as much protection.
Extending the life of decking boards
if you do build a raised bed out of decking boards and want to extend its life of it then consider using a plastic membrane behind the boards.
This is just a layer of plastic sheeting that goes in between the decking board and your soil. It will stop the decking board from soaking up moisture from damp soil and make it last longer.
If you do this and also extend the plastic membrane across the ground to work as a weed barrier then make sure you put some drainage holes in it! You don’t want to inadvertently make a muddy pond.