The new generation of battery cages on commercial farms do give hens more space and nest to lay their eggs in but one thing they cannot do is provide a dust bath. This is a vital social activity. It's a chance to get rid of ecto-parasites by scratching dust and soil up into the plumage and shuffling it around. There is nothing they enjoy more on a warm sunny day. Animal behaviorists call it "comfort behaviour" one of those natural activities essential to animal welfare. In this case they destroy the flower bed at the same time.