when youre talking energy efficiency, usually LED is the way to go, not to mention no mercury risks like with CFL.

Lumens being the measurement of amount of light that something is putting off--i would go with that. Since plants basically mostly just use red and blue light (red for flowering, blue for foliage growth), a lot of LED bulbs out there have been designed specifically for plants, and have just red, and blue colored diodes.

So just ignore watts and look for most amount of lumens? Whats a good amount of lumans I would need for a 3x3 bed and a 4x4 garden bed?

HPS for flowering and metal halide for veg growth will give you better bang for your buck than either CFLs or LEDs once you get past seedling stage.

Go with LED. They use about 1/3 the power of HPS/MH and wonâÂÂt heat up your grow tent. They are cheaper to use in the long run because of their 50,000 hr life span. You'll spend a fortune buying replacement bulbs for HPS/MH never mind the cost of the required ballast.

For a 4â x 4â tent, you would need a full cycle light pulling at least 350 watts from the wall. Some grow light companies to look at are Platinum LED, Advanced LED, Intelligent Gro, Hydro Grow, CA Light Works, Kind, Spent some time learning about LEDs. 5 years ago LED technology was not advanced, but not there are 3, 5, and 10 watt LEDs out there.

Lots of YouTUbe videos to watch too.