One thing my mom used a LONG long time ago.. it *did* work for a while, was used kitty litter. This is before clumping litter. We used just regular clay litter & would sprinkle it around the perimeter of our garden to keep the bunnies out. It worked for bunnies, but not deer. The deer decimated the garden, but bunnies kept clear. Only problem is that it has to be replaced quite regularly as it will deteriorate & decay into the ground (the clay). I don't know about clumping litter.
I found this article when I did a quick search. I didn't know that beebalm could be classified as a bunny deterrent!
http://www.ifplantscouldtalk.r...
There are few truly rabbit proof plants. If the rabbit population is high and food is scarce, many plants will be on the menu. Some plants will be eaten when young but avoided once mature. There are some plants that rabbits and squirrels will avoid if there are alternative food sources. Some deterrent plants include the following:
Annuals such as Ageratum, Campanula, Impatiens, Forget Me Nots, Scabiosa and Cineraria;
Perennials such as Achilleaa(Yarrow), Amaryllus, Aqualegia(Coral Bells), Artemesia, Aster, Tuberous Begonia, Campanula, Cyclamen, Dahlia, Dicentra (Bleeding Heart), Digitalis (Foxglove), Echinacea (Coneflower), Ferns, Gaillardia, Hemerocallis (Daylilly) Iris, Monarda (Bee Balm) and Verbena.
Groundcovers such as Bougainvillea, Hedera (English Ivy) Lantana, Pachysandra, Solanum (Potato Vine) and Vinca
Shrubs and Herbs include Buddlea( Butterfly Bush), Boxwood, Camellias, Holly, Juniper, Lantana, Lavender, Rhododendron, Rosemary, Salvia, Mexican Sage, Lilac, and Viburnum