Is it true that if, at a certain time, you cover a plant with contractor bags it makes bigger buds Sent from my iPhone using Grasscity Forum
Probably the opposite. You're depriving the plant of light. It'd probably cause the plant to stretch a bit, too.
I did that years ago when growing in Pa. It would force the plant to flower and give me a few extra weeks in the flower stage.
Also, if it's really hot, you could "cook" your plant if you leave the bag on during midday! The black bag traps the heat quite effectively.
Williams wonder a strain from the ealry 1990s, needed to be forced flowered as this for 10-14 days or so or better grow in a pot and switch of the light earlier, I know of no other strains needing this