yes you can use the tops of your plants for clones
you can flower her anytime depending on what size you wanna end up with. personally i put mine into 12/12 when they reach 9-12". Usually end up with a 3 foot plant depending on strain. I also don;t take my cuttings until they've been in 12/12 for a week or so. The stems are thicker and root faster than the weak, flimsy cuttings from a plant in full veg. Did I mention I use hps from start to finish ???? Yuuup. Gotta MH but HPS makes for a fuller, stronger plant.I'm growing from seed, meaning, i have to wait 6 weeks before i can cut clones. Does this mean i have to wait 8 weeks in veg before i can flower?