and why do you suggest only doing 2 or 3? i dont understand because i have a mate that did 3 under a 65w cfl in a smaller box and like i said it got me high as a kite
so i dont get why i can only do 2 or 3 even tho ive gone for a better light and setup.
thanks for the reply
He did 3 under 65W of fluoro and got 10g per plant? You have nearly 4x as much light. Your plants will grow much bigger. With a 250W MH over 5sq feet of canopy should yield 60g per plant! The rule of thumb is 0.5g per W of light. That's for MH. cfls yield less but I dont know how much.
The final size of your autos will depend greatly on how much light you put in. Another rule of thumb is that for every sq ft of canopy you need 50w in your MH bulb (I dont know the equivalent for cfls). It's what I have in my grow and my autos wanted to finish in 12L and 20L pots! Each plant needed about 20" x 20" of floor space. Your plants should be a lot bigger than the ones your mate grew.
Canopy is the surface of green leaves that the plants present to the light. If you imagine looking down at the plants from the light buld you will see a mat of green. This is the canopy. The maximum size of the canopy is determined by your bulb. In your case 5sq ft. Outside of that area the intensity falls away rapidly. Experienced growers try to train and manipulate their plants so that this area has few gaps and branches are not obscuring each other. Once you have your canopy filled adding more plants will not increase your yield.
You have 3' of height? Allow 9" (at least for the pot), another 9" (at least) for the light and the clearance above the plants. You are left with about 18" of height for the plant itself. If your plant wants to grow taller then that you are going to have train her to control the height which means she will spread out more requiring even more area.
Now what happens if you grow three plants and you run out of canopy space in the middle of flowering? What happens if the plants become pot bound and you need larger pots? The pots can't be much taller than 9" so they have to be wider. If you take out a plant, where are you going to put it? You may find it a struggle to manage just two in that space?
You've never grown under a 250 MH ( true? ), never used this cab and never grown autos before, in fact, never grown at all. In light of that, I suggest you play it conservatively and leave yourself some room for things to go wrong. Just my opinion. It's your grow. IMO three plants is dodgy at this point. I would recommend two on the first grow.
If you were growing photos, you could control their size by the length of the veg period and pruning. With autos the plant decides.
heres an idea and heres some of my plants from my cfl grow
but im still not 100% sure im doin the rite thing