Your biggest problems will be wildlife, and insects / bacteria. Then maybe the strain if its a toss up, make sure to scan for hermie's, even outdoors (if you can get to it, i know most guerrillas cant get to it everyday like us indoor folk, or people who otherwise have it close by). I recommend killing an animal and putting the carcase a few yards / meters away from the garden, and leaving it to rot. It will deter many vegetarian animals from venturing near by (the predators of marijuana grown outdoors, ESPECIALLY DEER) . The bigger the better, if it stinks too bad, put vicks or some vapor rub on your upper lip before tending to the garden, it works for the morgue, so it works for that too, lol. Also because it is outside, and subject to pests daily, I would spray them once every week, or two with something to irritate bugs, and kill on contact. Alcohol + soap + water is a good one. It fries a lot of larvae and smaller insects (at least indoors i know for sure.)
Hope some of this helps friends.