Square feet and Watts.............?

[puff4twentynow]

What is the amount of watts you want to have per square foot?

Example Question: Is one 400w HPS enough to grow two plants within 4 sq ft.?

puff4twentynow Reviewed by puff4twentynow on 04-24-2005. Square feet and Watts.............? What is the amount of watts you want to have per square foot? Example Question: Is one 400w HPS enough to grow two plants within 4 sq ft.? Rating: 5

[Zandor]

The magic number is 50 watts per sqft. More light equals more buds and light from the top and light on all sides will grow more bud then just one light above. The problem with top only lighting is penetration to the lower branches. With top lighting only you will only get bud from the top 1/3 to 1/2 of the plant.

Yes 400w is fine for 2 plants. Use Mylar on your walls to increase the light to the lower branches it does help.

[puff4twentynow]

how many grams per watt should grow with 400w HPS for 4 sq ft @ two plants flowering for 60 days?

Can anyone answer that?????

[llamaman666]

Depends on veg, strain and all sorts of other variables. if you veg like 30 days it would be something around 3.5 ounces a plant. that is a little under 100 grams

[BILL THICK]

The magic number is 50 watts per sqft. More light equals more buds and light from the top and light on all sides will grow more bud then just one light above. The problem with top only lighting is penetration to the lower branches. With top lighting only you will only get bud from the top 1/3 to 1/2 of the plant.

Yes 400w is fine for 2 plants. Use Mylar on your walls to increase the light to the lower branches it does help.

Maybe you can help me decide on some lighting connsidering the factors
120 square foot room I was planning 1000 watt MH and 1000 watt hps from what you just explained would I do better breaking them down into several smaller watt lamps ? What might you suggest the best lighting arrangement ? thanks Bill Thick

[Zandor]

Bill
Light requirements can change with how you grow and your budget. I would be happy to help you but I need to know how are going to grow, the room size and height?

Will you be growing with soil or go hydro? If you are choosing hydro what method are you using?

How about budget?

Last what yield would you like to achieve?

In truth it takes about 3 grows before the equipment is paid off so budget for that. Saying you can upgrade later is one thing but you need a good base foundation to start. Good light, good nutrients, good air flow, cool temperatures, and a controlled environment.

[BILL THICK]

Bill
Light requirements can change with how you grow and your budget. I would be happy to help you but I need to know how are going to grow, the room size and height?

Will you be growing with soil or go hydro? If you are choosing hydro what method are you using?

How about budget?

Last what yield would you like to achieve?

In truth it takes about 3 grows before the equipment is paid off so budget for that. Saying you can upgrade later is one thing but you need a good base foundation to start. Good light, good nutrients, good air flow, cool temperatures, and a controlled environment.

Thanks for the response Zandor. I have a 10 ft X 12 ft room with an 8' ceiling(insulated attic above that). I am directing my efforts towards hydro, ebb and flow. Budget is not a major strain at present although could become one shortly down the road, but I prefer making every effort to produce a favorable harvest on the first crop, (however impractical it may be for my first grow-lol). Therefore I feel I would best be served by getting the proper equipment and necessary tools and nutrients.
My initial supposition leaves me considering 2 1000 watt high intensity light systems (1- mh 1 hps). But as I continue to absorb information and read opinions of those who are experienced I am leaning now to thinking I may want to break these into more lights with less wattage. thus I come to the point of asking your advice.
Also curious about distance(spacing) between plants . Any time and effort you may afford me would be highly appreaciated . peace

[rapid88]

Another way to have light reach all of your plant is to tie them down, as this exposes all the branches to equal light.

[Zandor]

What yield are you looking for? How much dry buds do want to grow for your needs?

If you want an easy start into Hydro Aeroponics or drippers are about as easy as it gets. You can build most of the equipment yourself.

So what is the number of plants or how many dry buds (total weight) do you want to grow?

[Beeblebrox.420]

The magic number is 50 watts per sqft

Disagree slightly. The number of watts per unit area will depend on the type of lighting, its efficiency and watts drawn per lamp. You want to shoot for about 10-15,000 lumens per square foot, which approximates typical direct summer sunlight. Lumens are more important than watts when it comes to grow lighting. Bear in mind that the lumes per watt figure for a given lamp will increase with higher wattages - in other words, the higher the wattage of a given lamp, the more efficient it generally is. I give typical lumens per watt figures for some common lighting types below, in order of efficiency:

Incandescent: 10-20 lum/w
Fluorescent: 35-100 lum/w
Metal halide: 80-120 lum/w
HPS: 90-150 lum/w