Andy wrote in message . ..
[...]
Maybe I could use cardboard as a mulch? If I was to cut it into
strips perhaps it would rot away after a while suppressing the
initial flush of weeds I'd get from an old plot.

I've tried this: the homeless slugs from three counties converged with
gratitude. It's also difficult to hold down. But, yes, it does rot
away; taking nitrogen with it, of course, as it's essentially wood. I
think it'll be great under old carpet, though.

Mike.