I have been told that if I add half a cup of tomato juice to my two bitches meals, that this will stop their urine making pretty patterns on the grass.  Not that I have much grass left after all the rain but I'm thinking forward to the summer!  Has anyione heard of this working or know of an alternative?
TIA

IMHO messing about with a dogs biological functions to suit us humans is not necessary - most of the time simply emptying a bucket of water over your dogs urine will dilute it sufficiently to reduce damamge to the grass.