In message , K
writes
George.com writes


You can essentially put anything in from already made compost to the raw
ingredients, some mushroom compost, any turf from around the garden (put it
at the bottom so it won't grow up),

The previous suggestion of simply building on top of the lawn also
leaves a layer of turf to rot down to humus.

layers of straw and manure. There is no
secret recipe, at least in my experience, apart from making sure it is a
balance of nutrients (nitrogen etc). It all depends on how long you want to
wait before you plant.

The cardboard suggestion is a good one or old hessian floor underlay can be
quite acceptable at keeping grass out (an old house being renovated or
perhaps a carept layer

Wool carpet only

. Avoid new underlays, carpets etc as they may have
toxic crap in them which may, note I said may, taint your veges) It will
eventually rot away.

Obviously any carpet which isn't 100% wool or other organic matter
won't rot, nor will most underlays apart from hessian
I used to have one of those pretend Persian rugs that were in fashion 20
years ago on top of our compost. It was wool and lasted for years until
at last it developed mould and had to be thrown away.
--
June Hughes