plants to big bloom room not ready. please help

I have some plants in veg that are already to big. About 30 inches tall and in 3 gal buckets. I have 7 feet of vertical grow space, my bloom room is full and will be for 3 more weeks. any Ideas on how to slow these down on height. I veg under a 1000 watt MH and bloom under 1400 watts of HPS.

Lower the lights if you can, or tie em down

If you have a significant enough time for them to recover from the shock, its a great chance for you to do some major trimming. While we all know people mixed feelings about how much and how often to trim. Basically all my branches are stripped to just the bud sites and the closest attached fan leaves. After I tie down all the side branches to the side of the pot. I also put a couple in a screen to try that out on a couple plants. It seems very extreme, and you'll be super shocked at how the plant looks, and how many leaves are on the ground, but I assure you we actually do this trim every run a few weeks before we go to flower. After an initial shock it creates some intense growth around the bud sites, and cleans up the plant for good air flow. It also allows plenty of light to get to the smaller perhaps formerly ignored smaller bud sites.