Quikrete or concrete in raised bed construction

Hi Folks:
In my vegetable garden I use 8-10 inch high raised beds with hardware cloth underneath primarily to defend against voles.  Wood sides do not last but a few years in my woodchipped garden space.  I'm considering concrete sides as an alternative.  I have experimented with concrete blocks, but they are overkill.  Seems like I could make some thinner walls using a form and Quikrete or another concrete mix.  Should I be worried about contaminating my soil?
Thanks in advance for your thoughts!
Rob

Can you use steel, such as roofing iron cut to the height you want, and held in place with star or T pickets?
Also, quik crete would be very expensive to use and concrete mix to be good value needs to be mixed, and I guess you need a fair bit so bulk sand and screenings, bagged cement and a concrete mixer would be needed.
Why is 2" wood not good enough?

I don't think concrete is particularly a thing to be worried about in the garden. In my opinion the main problems with it relate to the manufacture and distribution of it as a material - high embodied energy and pollution of heavy metals near the manufacturing plants. When trying to find some useful information for you I found quite a few papers on using cement to stabilise metal contamination of polluted soils, which implies that the concrete itself would not be a problem.
You could check this thread out: https://permies.com/t/83626/Making-raised-bed-edges for other suggestions. One way to reduce the amount of concrete required is to use it to fix stones or reclaimed building materials perhaps.

(edited for grammar)

We've moved to large rocks and lime mortar for many of our beds. There's also the option of hypertufa, which is a sort of low-cost concrete. We make ours with crushed lime rock, lime putty, and wood ash. By making a stiff mixture, it can be either troweled on in layers, built up in successive days, or formed. My standard mix is 6 parts aggregate, 2 parts lime putty, and 1 part ash.

The finished product is a bit soft but hardens with time. In our climate it grows a nice coat of moss and liverworts. You can add a little portland cement to make it more durable and speed setting. When you demolish it, the pieces can be broken up and used for aggregate or as a soil amendment where calcium is needed.

Might I ask what type of wood you have tried in the past? I wonder whether some especially rot-resistant species like cypress or teak would be worth sourcing.

Hi, If you have access to lots of rocks then by making the chinese motar with sticky rice and lime it would be cheaper and more earth friendly.  

Hey Rob!
I struggle with this durability problem myself.
You might want to consider cement board, or large tiles, if you can get them cheaply.
I have used each of these to good effect.
Concrete in the garden should be fine.
For casting your own walls, there is this series of videos that go into great detail on various mixtures and how to:

Ditto what Nancy said.

Most cement is a mixture of oxides of Calcium, Silicon, Aluminum and Iron.  By itself, that is pretty benign stuff.  She is right about the embodied energy, but if you have some stuff laying around, why not use it?

Eric

Thanks for your suggestions folks!  Very helpful ideas!
To answer your questions, pine is the affordable wood in my area and it does not hold up in my humid environment beyond a few years.
Thanks again!  Rob