how many plants under a 400w light
- Thread starter milkjug
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sunny747
Well-Known Member
400 watt hps is approx 54,000 lumens.. For flower u will want between 5000 and 10,000 lumens per sqft.
With a 3x3 footprint you are at 6000 lumens.. If you have good reflective material and you train them you can go 3x3 per light. Stick as many plants in that space as you like.. Yield will be probably .75 g per watt no matter how many plants you have. Four 3 ft tall plants in #3 pots would probably work well. Either that or one real good scrog plant vegged for 10 weeks..
For veg you could probably get away with 4x4 depending on the reflector..
With a 3x3 footprint you are at 6000 lumens.. If you have good reflective material and you train them you can go 3x3 per light. Stick as many plants in that space as you like.. Yield will be probably .75 g per watt no matter how many plants you have. Four 3 ft tall plants in #3 pots would probably work well. Either that or one real good scrog plant vegged for 10 weeks..
For veg you could probably get away with 4x4 depending on the reflector..
sunny747
Well-Known Member
Something like this would rock your Veg area...
http://www.htgsupply.com/Product-Growshop-Outlet-4'-4-Lamp-T5-With-Grow-Bulbs
http://www.htgsupply.com/Product-Growshop-Outlet-4'-4-Lamp-T5-With-Grow-Bulbs
gardengardian7
Well-Known Member
You can do 5-6 plants depending on how long you veg and according to your Gspace. But as a strategist over all... I do 4 of the most beautiful with a nice lst excercise under the 400w hid with a really good cool tube HOOD!...
Smootherpete
Well-Known Member
4 plants, mainlined to 8 colas in 3 gallon pots should be good. Veg 2 months keeping them low by mainlining to 8 colas...kinda like what I've done here but with a 600 W MH/HPS combo. Tomato rings help keep those heavy colas up in late bloom. I used to do 2 - 5 gallon pots but figured I was wasting precious space so now I started 4 - 3 gallon pots...this harvest is gona rock!
Smootherpete
Well-Known Member
Scrogs sucks for perpetual grows if you ask me...by growing 4 plants mainlined to 8 colas, I can start flowering 4 plants while still trimming my harvest. Scrogs have to veg in the grow tent a while. I have a homemade veg box made out of plywood wired with 6-26 watt cfl bubls. When I harvest, I transplant the ones from the veg box to the 3 gallon pots in the tent.
sunny747
Well-Known Member
Can you show me a pic of your rings? Hard to see. Wondering if it's the tomato cage type setup.
Alienwidow
Well-Known Member
I like four plants under a four hundred. All at different stages equals a constant supply of weed and the bottom stuff will get light if the space isnt crowded.
Tone5500
Well-Known Member
I didn't realize you were doing a perpetual grow sorry
auswolf
Well-Known Member
4 per light works well, get a reflector with good spread.
Start to mainline ASAP, keep plants short with a big canopy, keep your light close.
Here's a pic of my current grow 10x5 tent dual 400w hps at around 4 weeks.
My plants are not mature yet, still need a few more weeks to fill out my canopy aswell.
But by the time I flower I will have hundreds of main colas lol.
Start to mainline ASAP, keep plants short with a big canopy, keep your light close.
Here's a pic of my current grow 10x5 tent dual 400w hps at around 4 weeks.
My plants are not mature yet, still need a few more weeks to fill out my canopy aswell.
But by the time I flower I will have hundreds of main colas lol.
Smootherpete
Well-Known Member
There is not even 10 days growth between top pics and bottom one! Had to veg these ones for like 10 days or so in the tent before switching to 12-12 cause they were cloned a little late. I also like to keep the MH for the first 2 weeks of flowering to keep them bushy, I find they stretch more if you switch to HPS too fast.
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Thanks for all the replies. I'll try four on my next grow. I have five under it now and they seems a little slow. I'm not sure what mainlineing is but I will look it up. I have already successfully tried topping them all twice. They all look happy and healthy just not growing as quick as a buddies are under cfls. Thanks again for the advice.
