This is the biggest one with a few not far behind. My space now isnt an issue as I have my home to myself. Ill be making my grow box on fri. But I want to flower fairly early since its my first grow. I want to learn to manage a small flower before I invest too heavily. So what size is safe to start flowering? I read that my plant will roughly double in size while flowering. That true?
i think the air is too dry in your grow room your plant is drying up. Mist it with a spray bottle a few times a day or try to get the humidity up in there, might even try putting a small plastic dome over the seedling after watering. CFL lights can be placed close to the plant... i use them for veg work fine fore me. For a flowering light i would recommend something like. this
http://www.homedepot.com/p/ViaVolt-...-White-Grow-Light-V150/203288965?N=5yc1vZc9h4
As far as your growing space, I find 4x4 to be a nice manageable size to grow in. also depends how many plants you have
Depending on your canopy spacing, plants placed too close together that don't get good air flow will run into moisture issues and that can lead to powder mildew/rot... that stuff shows up one morning out of the blue no warning and can wipe out your whole crop.
I find 3-5 hours after lights on if your fan leafs have water droplets where the leafs over lap (dark hot spots) condensation forms. This is GOOD. it means your moisture levels are right. you DONT want that moisture build up staying around all day tho that means it's a bit too moist in your room (even the fans aren't drying the moisture out). If at ANY time you have water droplets/condensation forming on the bottom of leaves this is a bad sign. BTW all this come at post week 2-3. right now your plant is just a seedling don't need to worry about what i mentioned but when it's got 4-5 nodes, watch humidity levels.
Your plants stretch during flower is all gonna depend on genetics, nutrients, growing conditions, light cycle, growing methods. If you have a heavy sativa leaner your plant is gonna be quite tall. if you have a heavy indica you'll have a shorter plant, generally. Hybrids vary in size. I would consider topping your plant(s) and feeding organic nutes using a K.I.S.S approach.
All the best