A 7-8 foot tall plant, grown by the sun into a large bush, will have to be planted in the ground, unless you plan on watering it every day or are using a small swimming pool as a planter.
Cannabis leaves are a distinct color green. It may not look like it to us or to the inexperienced, but observers from the air can tell the difference easily with training. Plant placement is critical, and planting other plants nearby can certainly help, though I'm no outdoor grower and don't know for sure what kind of cover plants to use.
Good luck with it!