Hi we had a large decking area when we moved in 8 years ago, made with standard 'slatted' decking that the previous owners got from B&Q. We ripped it up & used the decking lengths to make 2 large raised beds instead. We lined the insides with heavy black plastic pond liner.
I was told recently that there may be a toxin problem with using recycled decking lengths - has anyone else done anything similar or know any more on this subject?
You often here about potentiual toxin problems from treated would used for raised beds or compost heaps etc. However, I think they are often exagerated. I bough a job lot of treated gravel boards (intended for puttina alonf the botom of fences) from Wickes about 10 years ago and have been using them for raised beds and compost heap bays etc ever since. I haven't noticed any problems as far as y plants are concerned. After a year of two out in the elements I would be very surprised if your decking boards are leaching out anything at all.
I wouldnt be too worries but I know from experience that older treatment techniques used a bunch of pretty nasty chemicals including arsenic.
Im sure that if you minimise the contact with the soil with the plastic liner any contamination would be very minimal.
Hope this helps
Thank you for the responses - the age of them is certainly a consideration in terms of 'nasties' but then again as you point out, there must be a point where there's v.little left in them (they were never looked after with extra treatments when they were actually used as decking).
I've also sent an enquiry to B&Q to see what they can tell me about the decking they were selling 10 years ago and what their advice would be in using it for raised beds - I'll post any reply I get.
An update - it took a month but B&Q finally sent this back :
"We don't hold records of decking treatments going back that far, however, since the use of CCA's in timber treatment has only become restricted in the EU within the past 10 years or so it can't be ruled out. It would therefore be advisable not to use this decking for the construction of raised vegetable beds.
Timber suspected of containing CCAs should not be burnt. Take advice from a recycling centre as to the best route of disposal."