Try making a mirror mobile (I'm not kidding). They are mobiles made from a coat hanger, with several little square pieces of 1/8" plexiglass mirror. Put the mobile and each piece of mirror on monofilament fishing line & swivels, so they spin with the slightest breeze. Hang two or three in the back yard, or wherever your garden is. At night, they catch the ambient light (street lights, back yard spot light), and they reflect. Drives the deer nuts, because they can't figure out if it's a predator or not.
It also drives the rabbits and squirrels nuts. The crows, they could give a shit less. Since the City started the "crow abatement" program, they have all moved to my neighborhood, darned flying rats that they are!