Hello,

I am interested in making raised beds in the garden. I have not done
this before, so I have a couple of questions:

I am thinking of using wood due to cost, i.e. it is cheap. I see some
people use pressure treated decking boards like these:

http://www.wickes.co.uk/Wickes-Premi...-2-4m/p/101000

Is this the best timber to use?

Is there a danger of the preservative leaching into the soil? I was
hoping to grow some vegetables to eat and do not want to poison
myself!

Some web sites suggest putting a plastic sheet between the wood and
the soil to prevent this contamination but other web sites do not
mention it; is it necessary?

What is the best way to screw four pieces of timber together to make a
rectangular raised bed? I was thinking that I would need to sue a
piece of 2x2 in each corner and screw into these. Half of the 2x2
could be buried in the ground to anchor it.

However, is anchoring necessary: will the weight of the soil no hold
it in place?

Do I need to 2x2 at all, as I have seen some beds where the ends have
been butted together and just screwed through.

What is the best way of doing things?

Thanks,
Stephen.