Warning, Soapbox Alert:
I'd stay away from mothballs. They are usually composed of the chemical para-dichlorobenzene. It isn't as nasty as some but still, it's a carcinogen and mutagen and once it seeps into your soil, may stay there for a while as it is not particularly water soluble. It is not a rodent/rabbit deterrent and is not marketed as such. It is manufactured as a clothes moth repellent. Many people are susceptible to its fumes (it is highly volatile) which in high concentrations can lead to liver and kidney damage.
Always, always, always read the label on any chemical you use in your garden or your home. Never us a chemical in a manner other than recommended on the label. If in doubt get the Manufacturer's Safety Data Sheet (MSDS). You can find them easily on the internet.
You're planning to eat the stuff in your garden, why add unnecessary poisons to your food, your garden, and your living environment?
And Marigolds deter insects, not furry animals. They are natural insect repellents because they manufacture pyrethrins.
Mechanical barriers against rabbits are the safest for you and your family and, in the end, the most effective.
"The only thing I have to eat is Yoo-hoo and Cocoa puffs so if you want anything else, you have to bring it with you."