I have a raised garden bed made of corrugated iron and wish to set it up in our concrete backyard.
It doesn't have a bottom, so do I need to do anything in terms of drainage/linings?
Welcome to Workshop @kay23 and thanks for your question. This is a popular topic so I'm sure Workshop members will be happy to share their thoughts. Let me tag @MitchellMc so he can start the discussion for you and share his advice.
What are you planning to grow? There's a popular discussion called What to grow in the garden in March that you might find of interest once you've set up the raised garden bed.
Please let me know if you ever need a hand getting the most from the site, or have any feedback about how we can make Workshop even more useful to you.
Thanks again for joining in the discussion,
Welcome @kay23, to the Workshop community. Many thanks for your question, I'd be happy to help.
If you would like to stop sediment escaping onto the concrete pad, I would advise lining the bottom of the garden with Pillar Geotextile Weedmat. It has fine mesh to stop larger pieces of potting mix escaping under the bottom edge. It will also help reduce the amount of dirty water being flushed onto the surrounding area after watering or rain.
There is a great Workshop article How to build a raised garden bed by experienced horticulturalist and community member @Adam_W that I would encourage you to read. Step six, where Adam uses drainage matting and advises to lap it up the sides of the bed, should be of particular interest to you. There’s also helpful advice in the beginner-level project How to build a simple raised garden bed.
Thanks again for your question. It's great to have you join the Workshop community. If there is anything else I can do to assist, please feel free to let me know.