I would think that covering your outdoor plants with some sort of black plastic or whatever opaque material you intend to use would greatly increase your risk of budrot. The plants transpiration process will probably build up water/dew inside the bag and have no way to evaporate. Indoors you can still run fans and ventillation so it's not a problem, outdoors you would basically be suffocating the plants. I wouldnt risk it for just a little extra resin production, you could end up pullin that bag off and seeing a poop brown fully rotted plant and all your time and efforts will have been wasted.
I would focus on actually getting the plant to mature properly and walking away with a harvest before I would start foolishly experimenting !
good luck though, Peace