Thanks Hawkwalk Somebody else told me that lawn weeds may prove a problem but if the basket only contains annuals then I'm not too bothered. I'll give it a go.
Yes I believe it would be OK, I used to know an ex gypsy family who bought a small nursery, they would often talk about raking moss out of a lawn to line the hanging baskets they sold, in fact if they could get someone to pay them to demoss a lawn they were even happier, got paid twice.