hmmm was thinking of a good response for this, my natural instinct would be a bassat hound dog, this dog could guard your plants and keep away any rabbits or animals that could be harmful to your girls
however after deep consideration, if you have a dog tied up to this location, it may attract people/persons to play with the dog, which in the end makes your security situation a problem...
last but not least and i feel this strongly will help in your aid to keep away humans/rabbits/other harmful creatures to your location, would be to simply buy a lion, people can get past a dog, but NOBODY fvcks with a lion