We're visiting relatives in California, and something is devouring their basil, geranium, and lemon balm--in other words, plants with aromatic oils. Could this be a rabbit?
Ask them what critters they have and what the damage looks like for a decent diagnosis.
Nonetheless, if I were to plant basil in front where the rabbits roam, it'd be gone in one night. Since we don't know what kind of geranium, I can't comment on that. I would expect Melissa to be rabbit resistant.
Slugs and snails eat lots of things.
One of the things I enjoy about the Front Range that drove me crazy in CA was the slugs and snails. But surely there can't be anything but WAGs for this question. Could be anything with the paucity of info provided. Surely far up on the list for lack of info.
may be it's the japanese bettles. They almost finished my basil plants last year.
Actually, despite my "paucity" of information, rabbits is a good WAG. They have seen a rabbit skulking around. I just wasn't sure whether rabbits eat basil--they've never eaten mine in NJ. FYI, the geranium is 'Brookside,' or cranesbill geranium.