You could scatter some beagles in your garden...sorry, couldn't resist.
There are rodent repellents available at your local garden center...find one that's marked for bunnies, and try that. Some people will use fox or coyote urine on small sponge bits scattered around the area, but it may attract the foxes and coyotes (which isn't good for the beagles...oh, forget that, you don't have the beagles yet, do you...).