In the booklet Companion Plants and how to use them from Helen Philbrick & Richard B. Gregg 1966 I read:
Rabbits don’t penetrate through a plantation of onions. Every member of the onion family, even the ornamental Alliums, protects the garden against rabbits when they are planted like an edging around a border. This simple way of protection should be applied more often.
Well I can’t agree more. It works perfectly. Last year rabbits attacked my dahlias. They are still, but not in the beds where I planted onions around.
More tips from the booklet (which I’m going to try):
Slugs can be kept in distance by oak bark chipping or oak leaves. An extract of absinthe (Artemisia) sprinkled on the soil in spring or autumn keeps them away because of the bitter smell. Wood ash causes them to exhausts themselves or even kills them.
Mint planted next to the front or back door keep ants from going inside. Common Tansy around the house or on shelves in the cupboard has the same affect.
Euphorbia lathyris (also called mole plant) keeps moles and mice at a distance.
There are a lot more interesting subjects in the booklet. Most of them have to do with cultivation in combination (as the title suggests) for the kitchen garden. Please tell me if you want to know something. I’ll look it up for you!!!