I've let my lawn grow long this year, for the first time. It wasn't intentional: the cable to my lawnmower had frayed. Then it rained alot. But the garden looked really pretty. In desperation (it was getting pretty long) I went at the tallest grass with the garden shears ("these are old school" my shear sharpener told me), just a savage cut like a knife and fork before my neighbours started catching me in the drive :) Later, I did a high cut with the lawn mower. All sorts of other low growing plants with pretty flowers have started to appear. I think I prefer the meadow look.