Old decking (presumably treated) for raised beds

[Right Shed Fred]

I have just taken over a second half plot, and this time, I'm planning the layout more carefully, to ensure better and more efficient use of the space.
Raised beds feature heavily in my new plan, I've found them really useful for keeping both weeds and (my) children out of the growing areas...

So I felt pretty pleased when I bagged a whole bunch of old decking on freecycle, as I plan to use this to make the beds.

However, I am now concerned that my decking treasure I was so pleased with just 24h ago, might be treated in some way which would cause leaching of undesirable and potentially health hazardous preservatives/insecticides/fungicides into the soil.

Am I paranoid or is this a justified concern?!

Help!

[nickdub]

Personally I wouldn't worry about using it - but if you want to be super careful stack it up somewhere where the elements can get at it over the next 9 months, then put it in its final place next Spring.

[veggiechicken]

If you're really worried you could line the beds to keep the soil away from the wood.

[Right Shed Fred]

Ok, so I am perhaps being a bit paranoid. It's old stuff from a guy getting rid of his decking, so it's a bit weather worn already. It doesn't look like it had any other treatments recently.

Lining it is a definite possibility... I'll look into pond lining and similar... I think lining it might come down to how much energy / patience I have left once I've finished making the raised beds

Thanks!

[SarrissUK]

Hi there Fred! I love the name lol

I wouldn't worry too much about lining it unless you have spare plastic laying around that could be used.

[burnie]

I wouldn't be too worried, the only things that are now still creosoted are telephone/power line poles, all the rest of the stuff is usually wax based and little of that is applied. Pressure treated means pressure was applied when applying, you apply pressure on a washing up liquid bottle to get the stuff out and I think a lot of the wood treatment is applied in a similar manner, just squirted on

[bikermike]

I personally use pressure-treated wood. In my view, the increased in duration of the wood is worth it with modern chemicals that have limited toxicity.

Pressure-treating means the wood is put in a tank with the preservative and pressurised to force more preservative further in
https://www.gardenfurnitureland.com/...alized-timber/

Pressure-treating makes no difference as a process in contamination risk - it depends what it's been treated with. I don't think anyone has used properly nasty stuff like creosote for some time.

[Urban]

I lined my beds with weed suppressing fabric when I built mine. Although it's probably not necessary. Just wanted to keep the soil from touching the wood

[Baldy]

though weed suppressant fabric lets water through...

sounds like its been out in the wilds for a fair old time so I'd think that anything would have leached out -

however - I'd like to point out that I'm not a bio-chemist with regard to either statement made in this post

[Stan79]

As Urban said above, it's maybe worth sticking some plastic on the inside of the wood anyway to help lengthen the life of the wood. I've used compost bags cut up and stapled them to the wood in the past.

[Right Shed Fred]

Thanks everyone for chipping in. It is indeed quite "aged" stuff so I think I'll be ok. I will look into pond liner/recycling existing plastic bags *like that later idea) to both stop the wood rotting and as a bonus is might stop any remaining stuff leaching in.

[Aberdeenplotter]

If you're really worried you could line the beds to keep the soil away from the wood.

Buiders Damp Proof is ideal for this and it will also help prevent the wood from rotting.

[Stan79]

Lining it should also help retain moisture as the wood won't be drawing moisture from the soil and losing it as the wood is warmed by the sun...

[Jwood0123]

I lined my beds with weed suppressing fabric when I built mine. Although it's probably not necessary. Just wanted to keep the soil from touching the wood

same here, I used weed fabric to line my planters, everything inside seems to be happy. I think it might also help with allowing a small amount of air to flow and allowing even drainage.