it takes an averaging 8-10 weeks time after switching to 12/12 for the plants to be done. the size of the plant at the time of the 12/12 switch determines how big. the plant will usually double in size once light has been switched. so if you flowere when the plant is 12 inches tall. it should be 24 inches tall when done 8-10 weeks later. hope this helps
As scratchrc said, it usually takes 8-10 weeks for a plant to finish flowering. How long you veg it is up to you. You can tell when a plant is sexually mature as the nodes start to alternate. This is a great time to start flowering. Plants will also start to show preflowers, which is great for weeding out the males before you start flowering. Alot of the first timer grow journals I've read through usually veg for 3-4 weeks before switching to flower. It's just dependant on how large you want your plant to get.
ive heard that switching to 12/12 before signs of preflowering can result in hermies. is this correct?
