flourescent for vegatative stage followed by hps for flowering

would there be a big problem running flourescent lights for your vegatation stages and then switching to hps for your 12/12 cycle? im trying to find a way to not kill my electric bill.

i havent really heard of anyone doing this but a friend suggested it would be a good way to get around a big grow. lets say 400 plants in 2 20x20 grow spaces. they would be light-isolated from eachother during the flowering stages. you would be 24 hours on during veggie stage for all 400 under the flourecsents and then when you were ready to flower you could have half on half off in an alternating cycle.. sounds like a good idea but im not too keen on the whole veggie stage being under some weak flouresents. for 400 plants you would be looking at about 20 1000 watt lights..

what say you?

Thats a quite common procedure, actually, and perfectly logical and correct.
Plants veg very nicely under fluors, but most people find they flower much better under an HPS.
Though I'm not sure people would bother about swapping lights for a grow the size you're talking of.

if it were a perfect world i would just run hps thru the whole grow but it comes down to the ability of what the building can safely handle. there are going to be 20 hps 1000 watt lights in there.

you must be a rich man, to have 20 1000watt hps,

sounds to me, you need to do alot of research in what your doing.

Fluorescent lights are actually less efficient for plant growth than MH or HPS. They are nice though, because they're cheap and you can put them right next to your plants without having to worry about burning them.

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Originally Posted by ebsters

you must be a rich man, to have 20 1000watt hps,

sounds to me, you need to do alot of research in what your doing.

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rich? no. not even close.

sounds to me like you make too many assumptions. pardon me, but i am pretty sure that by asking a question in a cultivation forum, I am doing research. but maybe thats just me. but thanks for your input its been extremely valuable. while we are at it, What are your feelings on the current trade deficit plaguing third world nations like India?:wtf:

I just feel that HPS during veg would yield faster growth and more than likely a better end product.

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Originally Posted by khronik

Fluorescent lights are actually less efficient for plant growth than MH or HPS. They are nice though, because they're cheap and you can put them right next to your plants without having to worry about burning them.

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That is the exact aspect I was wondering about. when you refer to efficiency youre talking about lumens per watt right?

First, before you get all snotty with the person asking about your 20 HPS lights, you should be aware that it is BEYOND stupid to talk about a grow of that scale (commercial) on the internet.

Also, be aware that this forum is geared towards people growing on a personal or med use scale.

But if you want to stick your neck out there, here's my input....

HPS in veg isn't as efficient as MH in veg for the simple reason that the plants use the light spectrum in the BLUE range during vegetatinve growth.

Flouros (tube shop lights or agricultural T5 fixtures) are very nice in veg under a couple conditions: 1) Lights must be very close to plant tops 2) Plant canopy must be VERY even and not too thick because there is little penetration. It sounds like you are planning on cashcropping- the method you will find most effective will be to take a shitload of clones, stick them under your veg lights as soon as they are rooted but not keeping them there very long, like less than 2 weeks, and throw them into flower as soon as it is apparent that they are indeed giving a bit of vertical growth.

Have you ever grown before? Do you have ANY idea of the risks associated with what you are planning? Do you have a space to safely absorb 20,000 watts of HID, a few thousand of flouros, and THOUSANDS of watts of climate control?

flours/ by type

these are not exact numbers but is what i can remember off the top of my head, after looking at soooo many types of cfl's, hps's, and flours.

t12-60-70 lumens a watt
t8- 65-75 lumens per watt
t5-70-80 lumens per watt
t5 ho- 92-100 lumens per watt.

while mh bulbs are 120-140lumens per watt
and hps bulbs are 140-150lumens per watt.

and what i was refering to is that 20 1000 watt hps, is enough to have a garden that is enough lights to cover a 150'x150' ROOM. You will have to watch out for Light burn, as if you setup your lights wrong, some will get to much light. Adding co2 to your setup would help alot with this problem but will not solve it. Not to mention that to add co2 to a space this big would costs some serious $$$$

i a moving to humboldt next month.

doin it with the clinics in mind. with papers, all legal. just had a question about that single aspect..

peace.

Quote:

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Originally Posted by ebsters

flours/ by type

these are not exact numbers but is what i can remember off the top of my head, after looking at soooo many types of cfl's, hps's, and flours.

t12-60-70 lumens a watt
t8- 65-75 lumens per watt
t5-70-80 lumens per watt
t5 ho- 92-100 lumens per watt.

while mh bulbs are 120-140lumens per watt
and hps bulbs are 140-150lumens per watt.

and what i was refering to is that 20 1000 watt hps, is enough to have a garden that is enough lights to cover a 150'x150' ROOM. You will have to watch out for Light burn, as if you setup your lights wrong, some will get to much light. Adding co2 to your setup would help alot with this problem but will not solve it. Not to mention that to add co2 to a space this big would costs some serious $$$$

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thanks. and sorry if i bit your head off earlier. the room is 50 x 60 or so.. maybe 50 x 70. I sort of thought 20 would be too much in there too but i havent taken measurements yet.

If I was you, the first thing (and I DO MEAN FIRST) I would have done is measure the room? Yeah, that makes sense to me. 20 1,000 watt lights IMHO will be too much for your room, though like you said, you haven't measured it yet. Way to go, stick your neck out there talking about a 20 light 400 plant grow that is going to happen, when you don't even know that it will fit!? Anyway, I am not being rude buddy, I (and president teddy roosevelt) am just saying this :

Speak softly, and carry a big [weed] stick, you will go far.

I mean - tell no one, and be ready to do "battle" when the time comes. By battle, I mean arm yourself with knowledge of your local laws regarding plant numbers, as well as any other information you can get your hands on. Obviously, please don't go outside and actually get a tree branch to hit someone with, but be aware of the dangers out there. Good luck bro (or bra), and peace!!

PS - I wanna see pictures of 400 plants being harvested ha! My hands are hurting thinking about all the trimming that would be involved.........:jointsmile:

general rule-of-thumb coverage for a 1000-watt HPS is a 10' x 10' area, but I'm sure you could add more wattage/sqft if you desired ... an old Rosenthal growbook claims maximum results are obtained at 60-watts per square foot, anything more is probably wasted ... I don't know how true that it is, as different types of lamps differ in lumens/watt ... :smokin:

Is 3500-5000 lumens p sq.ft accurate?

all i have to say is running 20-1000 watt hps is going to rape your electricity bill costs, not to mention to extreme amount of attention you will have to give 400 plants. it is hard to grow 40 plants, let alone 400.

Yup- my max was around 200 and hand watering all those bitches was, quite frankly, a bitch.
I'm much smaller these days, and more efficient to boot.

Well has anyone seen the new water cooled tube lights?Liquid Lumens But $400.00 a light is way out of the budget.Water and electric I dont know if thats a good idea.If theres no heat this would be good for small grow spaces.What do you all think? PEACE
:rastasmoke:

I think it's a great idea. Just waaaay to expensive for me.