Dont top them. You can tie them down if you like but the tops of the plant is where all the growth cells and hormones are. Mix some peat moss in with the soil if you can not pick up bails of promix or farfred. Use like atleast 80 percent peat so they can breath. I grow in 22 gallon container and well they are 7 feet wide and 7 feet tall. You can surround them with ferns. ( some grow 3 to 4 feet high. My plants produce pounds. So I dont get faking it out. Winter is here. "You mean force flower it? I would put it in 24 hour light. once you want to flower outside, to keep it short, for one to three weeks inside give her 14 hours of darkness. This will force flower her nicely and end the cycle sooner so she will finish smaller. You can supercrop aswell by working out the stem. It makes it thicker and slows the plants from growing up. You can twist(START SLOW) or bend her. or tie her down making a loop in the stem. That should keep her short. It may reduce yield as apposed to free growth but some plants get real tall depending on style light and genetics.

Hope this helps

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