Outdoor cats often mistake gardens for their litter box. You don't want your neighbour's cat pulling out your roses or doing her business in the middle of your tomato plants. Fortunately, there are several herbs that cats find distasteful. If you plant these around the edge of your garden, cats will quickly learn to admire your plants from a distance.
Lavender is a light purple herb that grows in stalks similar to wheat. Many people use lavender for calming purposes; it tends to reduce anxiety and promote relaxation and sleep. Lavender has the same calming effect on cats as it does on humans--a cat who has been exposed to lavender tends to curl up and take a nap. Planting lavender on the edge of your garden may initially attract cats because of the smell, but they will become too relaxed to venture inside.
Rue consists of yellow leaves growing off of thick stalks. This herb looks like a miniature tree. Cats detest the smell of rue, according to "Garden Plants to Repel Cats" on gardenguides.com. If you plant rue along the edges of your garden, it discourages cats from venturing inside. If you do not want to plant rue, "Garden Plants to Repel Cats" says that you can achieve a similar effect by sprinkling dried rue leaves along the garden edge.
Coleus Calin (Scaredy-Cat Plant)
Coleus Calin is a hybrid plant created by a German scientist, according to "Keeping Cats Out of The Garden." This plant, also known as the scaredy-cat plant, strongly discourages cats from entering. It grows blue flowers and smells somewhat like schnapps. Cats dislike this scent and will avoid gardens covered with it. Plant this along the edge of the garden, alternating Coleus Calin plants and rue plants. The easiest way to obtain Coleus Calin is to order it from Germany online.