[Hollyjim]

Hi all. Am new to the forum. This is my 1st post. Got my allotment after a two year wait last Thursday. I have a questions about raised vegetable beds. 1. Is it safe to use decking boards? I've seen articles saying it is fine and others saying defo not as there is high risk of arsenic and other contaminants. 2. If not deck boards what should I go for, price is an issue. And 3. If I used bricks 2 rows high. Or bricks turned on their end but didn't use any cement. Would this be fine and be able to take the weight of the soil or would it collapse. Thanks for any advice.

[AnneB]

Our next door neighbours on the plot have used decking for their raised beds, but it is quite shallow.  I have never heard of a problem with arsenic  before.

We have used recycled scaffolding planks from a scaffold company nearby.  Prices vary, but we paid £2 per plank.  Some are a bit beaten about, but fine for our purposes and quite deep.

I haven't tried bricks so can't comment on them.

[the Kergan]

I use sawn treated 6x2, two layers high to make a 12 inch high bed. The 6x2 does not bow out at the sides with the weight of the soil.

[shokkyy]

I've had four raised beds made from decking boards for several years now and they're absolutely fine. I could only think that references to harmful additives must be thinking of the old fashioned preservative methods for wood, as you'll find in most railway sleepers for example, but modern pressure treating methods are harmless.

[angelavdavis]

I used decking to surround my beds - they were £2.49 for 2.4m lengths from the big orange diy shop, compared with £1 per foot for used scaffolding boards locally!  I haven't heard about arsenic in decking, only problems with using pallets as some used for importing goods can have chemicals in their treatment or sleepers as shokkyy has mentioned.

I would rather have used recycled materials but they just weren't affordable for us.

The decking is still solid (I used it also in London for my raised beds and large planting troughs and it was still good after 6 years when we sold the house).

[Trillium]

The preservative formula for treated decking has changed in the last few years, about 10 years ago and the newer boards are safer to use for veg beds.  Prior to that, wood was treated with chromated copper arsenate, a fairly dangerous/toxic chemical. Both North America and parts of Europe decided it was too dangerous to use with human contact (handrails, play equipment, etc) so formulas were changed to Alkaline copper quaternary, a less dangerous preservative. It's safe for human touch, etc, but you still don't want to breathe in the sawdust when working with it. It's also the reason why previous treated lumber screws had to be changed because the new formula literally ate up the old screws, so new ones were brought out that were stable.

Treated lumber still gives the best duration for wood projects but you do need to use caution when you work with it. I choose a breezy day and stand upwind of the sawdust.

[davel831]

we are a big fan of raised beds. When we got our plot a year ago we found the main soil was terrible, we decided to put raised beds.

locating them was easy by ringing a scaffold company and they actually delievered for us as well. We treated them with ducksback to preserve them.

the only down side if you want to think of it as one is we had to ger 8 tons of topsoil delivered to actually raise the beds.

one of our neighbours uses decking boards but the depth isnt that great!

i think it is a matter of choicem and what you decide to do?

have fun

dave