Building raised bed - advice needed please
 

Hi,

I've just dug an 8 foot by 3 foot by 1 foot deep hole in my lawn. I intend to fill this hole with some of the soil that has been removed (broken up), compost, some sterilised loam top soil, manure etc.

My intention is to build a raised bed (raised by about 6 inches from the level of the lawn). I intend to employ square foot gardening in the bed.

Various web sites I've been to suggest using an untreated, rot-resistant wood such as red cedar. I've just enquired as to the cost of this wood and, unless my calculations are wrong, I'm looking at £320!! That's quite a bit more money than I want to pay, especially since I'll most likely be moving house in about 2 years.

Any other (much cheaper) materials I can use. Looking for something that will last 2 years minimum and not leak any dodgy chemicals into the soil. Will, untreated normal wood last that long outside?

Thanks very much

There are a number of ways you can go about it e.g.

1) Contact a demolition contractor and see if they have any old floor joist available.

Normally they will keep the best for re-cycling back into buildings but sometimes they come across stuff that won't be able to be used for such a thing, but would very suitable to your purpose.

This type of timber is generally well seasoned as opposed to much of which you buy today, so it should last for quite a few years.

2) You could use tanalised timber which as far as I am aware does not leech the preservative because it was placed by a vacuum process as opposed to painting or dipping.

A tip here would be to buy from a fencing supplier rather than a construction timber merchant, they use a lower quality wood, i.e. it will have some 'shakes in it and is probably be heavily knotted, which is OK for your purpose but not for construction purposes.

3) Then if you want to use materials other than timber you could use concrete blocks or path edgings.

The choice is your, but I would guess each of these suggestions are cheaper than cedar.

Hi Scotia, thanks very much for the advice. I will try a fencing supplier rather than a timber merchant.

Regarding tanalised wood, I've just found the following on the web:

http://files.recycleworks.co.uk/file...servatives.pdf

It states that tanalised or pressure treated timber is not safe around vegetable beds. Some of what it says (in relation to arsenic) is a little scary and it would obviously need cross checking but I think I'll play it safe and just use standard untreated wood - that web site reckons that even pine will last 5 years.

Cheers

Building raised bed - advice needed please
 

"borgs" wrote in message
...

Hi,

I've just dug an 8 foot by 3 foot by 1 foot deep hole in my lawn. I
intend to fill this hole with some of the soil that has been removed
(broken up), compost, some sterilised loam top soil, manure etc.

My intention is to build a raised bed (raised by about 6 inches from
the level of the lawn). I intend to employ square foot gardening in the
bed.

Various web sites I've been to suggest using an untreated,
rot-resistant wood such as red cedar. I've just enquired as to the cost
of this wood and, unless my calculations are wrong, I'm looking at
£320!! That's quite a bit more money than I want to pay, especially
since I'll most likely be moving house in about 2 years.

Any other (much cheaper) materials I can use. Looking for something
that will last 2 years minimum and not leak any dodgy chemicals into
the soil. Will, untreated normal wood last that long outside?

Is your garden the same dimensions as your hole, 8 ft by 3 ft? If so, it
matches fairly closely the dimensions of raised gardens I put in no so long
ago. I used garden sleepers, 100cm by 150 cm, which were seconds (they had
the odd gouge out of them or had bark strips). Being seconds they were about
1/2 the price of 'good ones'. I just happened across them and snapped up a
load there and then. They will last 10+ years easily and maybe longer. I was
looking at about 300+ dollars but got it built for 1/2 the price. If you go
down this line I guess the best place is to check out if someone locally
mills garden sleepers and whether they have seconds around for sale.

rob

We dug trenches all around the edge of the raised beds we built last year. Then we found some of the rigid log edging, about a foot tall, sunk this into the trench and used some metal fixings from local diy store to fix them together at intersections along the joins and corners.

Then we filled them with topsoil & planted.

So far they have stood the test of time well, although we are going to have to top the soil up slightly.

It was cheap to do, (we got the edging from a Homebase that was closing down so only cost us £1 each!, and easy to build.