plants growing too slow

I am on my 3rd try to grow indoors. I have a custom built grow box 2x2x4 with mylar sheeting on all sides and the ceiling. I have two plants, one Indica @ week 3, pic 1, and one Sativa @ week 2. I have 6x 100 watt Daylight CLF that hang about 4-6 inches from my plants. I tried using some food on my 3 week old with nutrients 3-1-5 and saw that it burnt my leaves starting at the bottom that made the tip of my leaves brown and crumble when i squeezed it. I only fed the plant one time with the nutrients a week ago but i didnt do it again because I thought it was too young to receive a lot of food. I think its better now but does anyone know when I should start using food? My main question is, why havent my plants grown a lot more? Is it because Im using CLF? I figured for how much Im using that it would grow faster but its not. With only growing 2 plants will a 100watt metal Halide or 150 watt? Is Sodium better or MH for how much it will cost to keep on? My soil is normal with not a lot of nutrients, below 1% each but is concentrated liquid food better or high nutrient soil. I will only transfer once, into a 5 gal pot but does anyone have suggestions on what to use on my next repotting?

Cfls are only good for cuttings and when you Veg very little. I would say get atleast a 150 or 250 hps brother. Also I highly recommend Advanced Nutes Carbo load. It will help fatten your plant even w/ a weak light system.

those are not growing *too* slow. Those "100" watt cfls are not actually 100 watts, they are 26. that is number that matters.

I cant say this enough Cfls really are not for flowering. Even if you had a ton of real 150 watt cfls they would not compare to an Hps or Mh.

I havnt tried hps to be honest, but I do honestly believe that good results (maybe not as good as that of a hps) are obtainable with cfls when properly deployed. I've had good results.

I dont hate on Cfls bro, I use Cfls in my veg room(cuz I dont veg very long) but nothing compares to a Hps or Mh cept the sun. Every true expert in here will tell you that.

This is an easy one, your lights are too far away. they effectiveness of the light really plummets as it moves away from the light source. get them about 1-2 inches from the plants. What strength did you mix the nutes at? what kind?

drewabu said:

I dont hate on Cfls bro, I use Cfls in my veg room(cuz I dont veg very long) but nothing compares to a Hps or Mh cept the sun. Every true expert in here will tell you that.

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yeah, I know that the pros will tell me hps or bust, but honestly, comparing the outdoor grows (yes, the got much bigger than the indoor cfl grows) to the cfls grows, in terms of quality of bud (consistency, potency, yeild numbers based on amount of plant material etc) the cfl is a force to be reckoned with. You just have to use a shit ton hahahaha.


I agree, your lights can be closer. you could also use more of them.

I used a full tsp as the bottle said and mixed it in a gallon of water. I think I need to reduce the amount of nutrients, probably half a tsp or less than that.

what about the temp in my box. it can get hot in there from all 6 bulbs but i do have a hole on top with a fan blowing in cool air but also I have a screen between the fan and hole to keep bugs from flying in. Whats the hottest i can have my grow box without hurting my babies or when they get older

Ive read that during veg you use daylight with 6500k that it puts out and then use CLF's with 2700k for heat. Is that right or does keeping the daylight bulbs the whole time ok?

Use a mixed spectrum, during both veg and flower. During veg have mostly blue spectrum and a bit of red spectrum, when you start flowering switch out some bulbs so you have mostly red spectrum with a bit of blue. for example-during vegging you should use like 1 red spectrum bulb out of every 3 bulbs you have(so if you had 3 bulbs total you'd want 1 of them to be red spectrum). for flowering have one blue spectrum out of every 3 red spectrum. temps shouldnt go over 90f, under 85f would be better. I would get a 250w hps if i was you. hell, with a force air cooled hood and remote ballast(the ballast put out alot of hps's heat, keeping it outside the grow area makes it so all you have to worry about is the heat from the bulb, and the air cooled reflector will take care of that. 400w shouldnt be a problem, youll be able to keep the light nice and close to the plants too. 4-6 inches away from the tops instead of 12-14 really makes a difference.

Water 'em. I'm willing to bet the if you give them a nice heavy watering, that you'll see a noticeable growth spurt, within 2 days.


Yes, they need more light too, I agree with that completely.

You want to use the fan as an exhaust and have a passive intake, do you have a fan inside the box blowing on the plants for proper stem development? full does is too much, cannabis need you to start small and work your way up. i start at 1/4 strength at 3-4 weeks, depending on if i think they are ready or not.

Is that a mirror in your grow area?

Want some real advice brother? Dont flower with cfls.Even a 250 hps would be worth it.

my fan sits on top of my box and i made a hole that about 1ft wide and between the hole is thing with holes to keep small bugs passing through the fan but it still reaches down enough to make my lights swing a bit and my plant just a little. Should I put it inside? I did try that but it was too hot in the box.

its mylar reflective sheets.

you need an exhaust fan, go find a 4 inch duct fan or muffin fan or pc fan.

Drop your lights down with your hand above the plant until you can feel the heat and tie it there... Also with the fan blowing air in from the top cut another hole in the bottom some where and put a screen there so that the blowing air has a way to escape therfore causing a perfect fresh ait cycle instead of blowing air in a box with no exit... The air inside would try to come out where it is being forced in creating a mild pressure inside your grow bow... Makes sense....