As long as it's not on your property it can't be linked to you, or proved to be linked to you, unless the police get a photo of you watering the plants or something. I don't mean plant them about 2 feet outside your back yard or something either lol, they'll know it's yours then. Always make sure you have a reason for being in the area where the plants are like take a bird watching book and some binoculars or something with you when you visit the plants. Finding a good outdoor spot for growing is pretty difficult, it has to be perfect. It has to be well hidden by bushes/trees but be open enough overhead to let the sun in. Plant somewhere were nobody walks like hikers or whatever, watch the area for a couple of weeks and see if anyone goes there. Never make a trail to the plants by flattening the bushes, if someone sees a path they'll walk down it just to see where it goes. The most important thing is don't tell anybody. No matter how good of a friend you may think they are they will still fuck you over. They'll either take it themselves or go around telling people about it. Trust nobody.
Check the soil in the area you want to plant in, it may be good enough to grow in. Growing in the ground means the roots have no limit to how big they can grow so the plants will grow big. Plants grown in pots will eventually become pot-bound, stunting them. If the soil is not good enough you can always dig in some quality soil/compost of your own with some sand or grit for drainage.
About helicopters- NEVER PLANT IN ROWS. This stands out like a sore thumb from above, especially in the middle of overgrown weeds and bushes etc. Plant in odd places, never make any kind of pattern, be as random as nature.
Good luck and be careful.