400 watt mh slow grow.

Discussion in 'Growing Marijuana Indoors' started by CheesyPeace, Oct 14, 2007.

  1. I was just wondering if a 400 watt mh is actually enough light to grow vegetatively because my seedling are 18" away from the light and growth is VERY SLOW.They are 8-9 days old very small and green so hopefully things will pick up a little...

    I am going to flower with the mh also maybe add an hps to help but if i dont if I just use the MH for flower Will it provide sufficient lighting for good bud production?

    Any comments please.
  2. From what i have read "im no expert!" MH's will be just fine for vegging. but your going to want something with a bit more umph to flower those babies. if you arent happy with the mh try some CFL's cheap to run and quite low on heat. give that a shot if you arent happy with the results of the MH's. With 400w MH you should be just fine for vegging. Apparently HPS are going to provide a more dense and abundant bud. That could be speculation but it seems the general consensus is HPS's for efficiency when flowering.
  3. show some pics. i have a week old seedling under about 300watts of cfls and its 3rd node of leaves (including cotledon) are showing 400w mh should b fine
  4. how many plants? what size grow room? Using any mylar or reflective material? What type of grow, Soil? Hydro? And what set-up? Sorry for all the questions, just like to know what other people are doing and how they're growing the sweet cannabis.

    I am not an expert by any stretch of the imagination, but you should be fine with the 400 watt MH for your veg, keep light as close to plants as possible (you should be fine with your current distance). Make sure your grow area isnt overheating, and think about ventilating your hood, just for good measure.

    As for flowering, I dont recommend MH for flowering, I would go strictly HPS, better light spectrum for flowering (closely matches the sun's output in the fall for outdoor growing). Also depending on the amount of plants, i would upgrade to 600 or 1000 watter for flowering. It'll really increase your yield per plant, and the buddz will be more dense and potent.

    I have a similar light set-up. I have a 400 watt in my 6x6 room for vegging, and i am gonna upgrade to 1000 watt when my babies are ready to flower.

    Check out my thread if you get a chance.
    "Hydroponic Paradise"

    High Always,
    Lavander Dro
  5. i have it all mylar covered and the light hangs 2 1/2 feet above the tray with a reflector. the grow area is about 4x3 and 2 feet high so relatively small which should equal a good amount of lumens but the little rockwool cubes are getting pretty wet at the bottoms and sides i am wondering if this is slowing growth.... anyone know the answer to this??/
  6. It might be that the rockwool is to wet. or it is just the strain
    what is the light cycle on I use 18/6 so it gets some dark. If they are
    seedlings they dont need much.Yes you can use the MH for flowering
    but the HPS works better

Share This Page