Nick wrote in message
It's to protect the sleepers from rot (if needed) and to stop soil
getting through the gaps (they are cut and laid vertically so theres
gaps where the sleepers are not square).


Ah, they are to be laid vertically, that's different. Staple it to the
sleepers temporarily and then nail/screw on a piece of wood all along the
edge to keep it in place and stop any chance of dirt getting behind it. I've
just used staples behind some log roll I've used and once the soil is in
even if the staples rust away the plastic does not go anywhere.
Another poster did mention that sleepers are very long lived anyway and
would them being covered on one side by plastic sheeting help things? (other
than keeping the dirt in place.)

--
Regards
Bob

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