How much light is enough light?

I am doing my first grow and I have four plants each in a 12x12 bucket. They take up 4 ft^2 and I am only running two 23 watt compact fluorescent bulbs for the entire area. They are 8 weeks old and only about 9 inches high. Do I need a lot more light or what? I'm kind of a energy conversationalist so i would like to avoid using a ton of energy but I also want to give the ladies as many lumens as they need. Any help would be great.

thanks

greenkeeper said:

I am doing my first grow and I have four plants each in a 12x12 bucket. They take up 4 ft^2 and I am only running two 23 watt compact fluorescent bulbs for the entire area. They are 8 weeks old and only about 9 inches high. Do I need a lot more light or what? I'm kind of a energy conversationalist so i would like to avoid using a ton of energy but I also want to give the ladies as many lumens as they need. Any help would be great.

thanks

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Hi, I hope I can help even though I'm relatively new to growing myself. But I've found from my research that Marijuana likes between 2500 - 3500 Lumens per sq. foot. Now, if you have 2 of the 23 watt CFL's, those will only put off about 2000 lumens each and in the long run will probably not be enough.

I had a couple of buddies grow a single plant under a 65W CFL and it took nearly 5 months to grow and harvest. Right now I have a 100W CFL and a 70W HPS beaming on 3 plants. And I just added a 30W CFL to the center of the pots so the stem leaves will get some light.

I would recommend if you're trying to be energy efficient and cost effective at least get a 100W CFL, it puts out about 10,500 lumens and seems to be doing me really well (even though HPS is generally better) I really have not seen much of a hit on my electricity bill. Cheers!

hey I suggest this its kind of expensive but so worth it dude your first grow is expensive but thats what you need I really recomend this http://cgi.ebay.com/400-watt-HPS-GROW-LIGHT-400w-High-Pressure-Sodium-Lamp_W0QQitemZ180136925188QQihZ008QQcategoryZ42225QQcmdZViewItem anything under this your going to just yield a enough for a blunt

you can get a 6500K 2 foot 54 watt T5 high output with ballast for under 30.00 online. that with a couple of 100 watt equivlant (26 watts each). thats a total of 108 watts, just about the same as a 100 watt regular light bulb and will be more than anoughf for three plants.

i vegged 12 plamts under 2 four foot t5's and 4 26 watt (100 watt equiv) and the grew fast, thick and strong.

keep in mind, cfls and t5's only put out 12 inches of usable light spectrum. so when they get over 12 inches keep the t5 just inches above them and lower the cfls beneath the canopy so you are getting 100% light penatration. you veg them 24x7 or to save energy keep your lights on a timer, 18 on 6 off. all light spectrums for veg state should be 6500K

when you are ready to flower you can switch to 2700K CFL's and a 2700K T5 bulb for $10.00 but you would be wayyyyy better off with a250 watt HPS. the light cycle changes then to 12 on 12 off so 250 watts for 12 hrs isnt much more than 108 watts over 18 hrs.

i know you wanna save electricity, but cfl buds are much smaller and fluffy while HPS buds are dense and much bigger. for the slight difference in your power bill you will get a much larger yield.

you can get a 250watt hps for well under 150 shipped on ebay or HTG supply.

HTG has a 150 watt HIGH PRESSURE SODIUM (HPS) GROW LIGHT that produces 16,000 lumens. In a 4 ft^2 area, that would be 4,000 lumens per ft^2. Isn't that about twice as much as I need?

Intensity is inversely proportional to the square of distance to the light source. So, no, it's not too much.

A 250 HPS is right-sized for 4sqft.