Question about yield with T5 and how to maximize it.

Discussion in 'Grow Room Design/Setup' started by SC45, Jul 27, 2009.

  1. Hi everyone I've been browsing this site for a few weeks now gathering information for the grow I will start when I move and first of all I would like to say that this website is a wealth of information and thank you for all of those who take the time to browse the threads and answer questions like the ones I have as well as posting all of y'alls tips and tricks. That being said I have a couple of questions I would like to ask concerning the issue of lighting using T5's that I would really appreciate some answers for.

    1) How much yield can i expect to harvest under 8 4' 24 watt t5's in a reflector and how can i max out my harvest? By this I mean how many plants would be ideal for this light set up and should I use LST, SCROG/SOG, or fim/top or in what combination in order to max out my yields. I ask the second half of this question because I read on Kamel's guide that LST is best for maxing yield with CFL's

    2) Will this also be the best way to minimize harvest time because for my first round time will be a factor.
     
  2. #2 Dilandau, Jul 27, 2009
    Last edited by a moderator: Jul 27, 2009
    I started my first grow about two months ago, under similar conditions as you. I started with a 4' 4-bulb HO T5 (Sunblaze) with some bagseed I had. Here is a rough run-down...

    -Started with 7 plants in smaller, 8" (1 gal, i think, pots). 4 ended up being male. When they showed their gender, I moved the females to 3 gal (12") pots and threw out the males.
    -All 4 bulbs were 6500K, blue lights.
    -It took about 5 weeks to go from seedling to where I was comfortable starting flowering. Each of my plants were between 12" and 20" tall by that point (The females were all the shorter ones, but stockier).
    -I used MG potting soil, and never had to add any nutes during the Veg stage...as it had a lot of N in it. Worked fine for me. Never had any issues with my plants. I literally just kept the lights a few inches away from them, watered every 3-4 days, and they were happy.

    I started flowering 3 weeks ago, and I'm impressed with the results so far. As I was able to see the gender of each plant within days of switching my lights over to 12/12. Couple things I changed up besides just tampering with the light schedule:

    -I started adding blooming nutes every third watering (by this time, I was watering every 2-3 days, as my plants just sucked the water up). The MG soil I had was low in other nutes, so needed to supplement, I felt.
    -Added 1 tbsp of unsulphured molasses per gallon of water once per week.
    -Switched 3 of my 4 lights to 3000K bulbs (the red ones).

    I did not LST my plants, and one issue I am running into is light penetration. The lower buds were just not getting enough light, and were small compared to the buds on the top 1' of my plants. Seems these fluoros just don't penetrate deep enough down. So I found a 4' x 8 bulb Sunblaze for sale (with all 8 working bulbs, too) for $120...and I can tell already there is a LOT more light. And I am thrilled to have scored such a nice grow light so cheap...had to brag. :)

    And this brings me to the point of your light...are you sure yours are 26w? Try and get the 54w kind. And you'll eventually need both 3000K and 6500K spectrum bulbs, too. You're only going to be putting out about 100w in a 4'x2' area. Which is gonna be about 10,000 lumens total...which comes to about 1.25K lumens per sq. foot. You're gonna need more. With the 54w bulbs, you'll get at least 20,000 lumens in that area. Enough for veg'ing, but you may want more when you get to flowering to up your yield. That is basically where I was...and I started out with twice the light you did. I think you want at least 3-5K lumens per sq foot...and if you can get more, even better.

    The only change I would do is next time LST my plants. From eyeballing the bud growth, about the top foot of each plant is doing well (about 18 - 20 buds / plant)...below that, not all that good. Hoping the more light will change that and give me more buds, and make the ones on top bigger.

    Best.

    Oh...and as for time. It was 5 weeks for veg'ing for me...and I figure flowering, although highly dependent on the type of plant it is, is gonna take around 60 days. Then about a week for drying / curing. So you are looking at, earliest, 14-15 weeks. You gotta be patient.
     

Share This Page