"Tony" tmg124AThotmailDOTcom wrote in message
...
Hello all
My wench wants me to build a vegie garden this weekend, but she is
concerned
that treated timber will contain poisonous chemicals. I need to raise
the
vegie beds, so any suggestions on what to use.
Thank you.



I have been looking into this myself recently. It depends on how big
you want the beds, how long you want them to last and what you want to
spend in time and money. Here is what I've found FWIW.

Manufactured concrete blocks tied down with reinforcing rods are strong,
durable, available and look OK but they can become expensive unless your
beds are quite small or you can use recycled materials. An option
probably worth costing to see if it suits you. You can also get
specially made interlocking concrete wall blocks for gardens and
retaining walls but these are even more pricey. They look nice and are
easy to erect, if money is not an issue this may suit.

Sleepers are very heavy for this application and the size will cost you
extra - you don't need the walls to be that thick and they are hard to
handle alone. Also used sleepers might be soaked in stuff like tar or
creosote which I wouldn't like in my vege patch, I would check this
before buying. Their size will make sleepers last longer than lighter
timber, except if you have whiteants in which case you are just
supplying more food for the little buggers, unless the sleepers just
happen to be of the species that the ants don't like.

Untreated hardwood of the more durable species is my choice. I am in a
rural area and its available and fairly cheap. If you buy such stuff at
the suburban timberyard you will probably not have any choice in
species, it will just be 'northern rivers hardwood' or something like
that, so it could be a lucky dip as some species will last well in
contact with soil and others will not.

As for treated timber ... the argument rages. Various authorities will
say that the heavy metals that make them poisonous to organisms causing
rot are locked up safely and others will say that it leaches out
significantly and you are at risk with an edible crop next to them. A
google search will give you a zillion words of emotive prose on this and
as far as I can see no clear answer.

David