Is 2- 40W 4 foot wide spectrum gro-lux tubes going to grow 3 or 4 plants?

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Dec 24, 2005
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this is my first grow and im trying to make it to the harvest with this one...i need to know if 2- 4 foot 40W fluorescent wide spectrum lights going to grow 4 plants? or do i need to get some new lights? and also is a grow box that is 4 1/2 foot tall and 2 1/2 foot wide going to fit 4 fully grown plants inside of it?

Please Help
You get a freebie here Ferg, after this you're gonna have to read a grow book.

Marijuana requires 6,000 lumens (at least) per sq/ft. for optimum growth. Watts & lumens are usually printed on each bulb and/or the package they come in.
Flo's emit 75 lumens per watt, so 4 x 40 x75 =12,000, or enough for 2 sq/ft.
(HPS kicks out 125 lumens per watt).

You can grow marijuana under flo's, but growth will be slow and you'll only get 1/3 the yield vs. HPS.

You only gave 2 diminsions of your grow box. If it's 2.5' x 2.5', your only gonna be able to get 2 pot plants in there. Have you ever seen a pot plant?
Good luck getting 4' flo's in there.
that is what ganga meant when he said good luck getting 4' flos in there . ferg. might've meant just setting them on top with no roof. that would be the only logical explanation for it anyway.
i said that my grow box was 4 and 1/2 foot tall, 2 and 1/2 foot wide, and 2 and 1/2 foot deep.
ferg...the point everyone is trying to make..."You can't mount 4 foot fixtures into a 2.5 ft box.", "if" you could, they would probably be sufficient to veg a few seedlings or cuts, for a few weeks.
hee hee frosty. I don't think "subtle" was registering..
hes gonna have a mess trying that anyways. the lights are still gonna be 4 in a half feet away from the plants .hey ferg walmart sells the 2 in a half foot and the 18in. floresent grow lights and there only 7 bucks a piece . even if you cant afford that you better atleast make your box 4 foot wide so you can fit your 4 ft. lights down in there real close to them if not like hick said you may have 2 weeks max . because they will grow skinny and tall and fall over on you being 4 in a half feet away from the light unless you have them on a shelf up close to the light within 2 inches or less or your wasting your time and ours .
my bad , walmart sells the 18 in and 24in . ferg what is confusing me is how is your box 2 in a half foot deep and 4 in a half tall unless you have a shelf inside?
ok since i moved my shelf down it is 4 and 1/2 foot tall, 2 foot wide and 2 and 1/2 foot deep but the shelf is cut to where i can slide my 4 foot light in the corners. i got some pics ill just show you what i mean.
here are the pics i took of my grow box and of how i can fit 4 foot tubes into my grow box. i planted 9 seeds in 9 seperate plastic cups with holes and gravel at the bottom for drainage. enjoy.










i know this is way off topic... but im baked. "I have that same desk lamp!!" Sorry about that.
are you trying to grow roses,cordylines or philodendrons, cause that sure in the heck dont have a marijuana setup. you were walked through with what you needed to do and your not paying att. ganga told you that you needed 6000 lumens per sq.ft them 2 40 watt fl. are only 1900 a piece now you do the math. also i told you they needed to be atleast 2 inches away from the light. people in here will just plain quit answering your questions if you dont bother to listen to them .
Well.. Lets be fair about it too. Yes Ferg didnt really heed to the advice from you more experienced growers but as for the lumens situation... Not everyone can drop $250 on a400w hps light. So if you dont have the money, ferg you can stick with the flos.
Although I'm pretty sure I've heard GanjaGuru say about 50 times that even a cheap 150w hps will triple your harvest.
But i do agree with skunk, dont bother asking for advice if you aren't going to, at least, attempt to follow it.:eek:
ty. ps the only way he is gonna be able to grow with them is if he builds the box 4ft 2 inches wide and get 2 more bulbs to match the lumens .and set over top of the plant like i told him.
i dont have all that much money to go out and get all this expensive stuff for my grow, i would like to get it but i am just working with what i have for right now untill i move somewhere so that i can grow it outside all year long...i have payed attention to what you have been telling me i just havnt had time to make adjustments yet...i have saved $20 so i can get some new lights, money is just really tight right now. that is why i am trying to grow marijuana. so i dont have to buy drugs and be short on rent and bills. i am trying but i just need some time to get the shit i need and install everything. i will try to get a light next week. but i hope that you guys dont think that i am ignoring the things that you tell me, i just havent gotten the things that i need...i will keep you guys posted. later
Ferg, Go to ( and check out the lights they sell.You can get a 400 watt system for just a little over a $100 plus shipping.I've had excellent luck with there products and you won't find anybody cheaper!
thanks for the advice, they got some low prices. ill be out of town for a week but keep an eye on my grow, thanks again man. later

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