IME, the effectiveness of LEDs depends on the color they are emitting. I have four panels, three that use 226 3mm bulbs and 13 watts of power and one that uses 112 10mm bulbs and 45 watts.
Of the three 226 bulb panels, two are more heavily dialed to the red spectrum while the other is far more blue. Placing them about two inches from the plant canopy, I get about 800-3,000 lumens depending on where the meter is placed. LED lights are very directional and moving the light a half-inch can make a big difference. The 45 watt lamp is much brighter, obviously, producing nearly 7,000 lumens two inches away.
I prefer how the plants grow under the LEDs vs. CFLs or regular Fluoros. The intranodal length is much less, even less than those plants in sunlight in the garden. The leaves are also much thicker. Total height seems to be about the same, except for an eggplant. The one under the light (and growing in a hydroponics system) is double the size of the ones in the garden, though it was transplanted about four days later.
As soon as I get another 45 watt panel, I plan on germinating a tray of seeds and charting their growth over a 10 week period then comparing them to how other other lights produce. AJ has said he will try using shop lights with T12 fluoros, if anyone wants to use CFLs or HIDs your participation would be appreciated.
Mike
Of the three 226 bulb panels, two are more heavily dialed to the red spectrum while the other is far more blue. Placing them about two inches from the plant canopy, I get about 800-3,000 lumens depending on where the meter is placed. LED lights are very directional and moving the light a half-inch can make a big difference. The 45 watt lamp is much brighter, obviously, producing nearly 7,000 lumens two inches away.
I prefer how the plants grow under the LEDs vs. CFLs or regular Fluoros. The intranodal length is much less, even less than those plants in sunlight in the garden. The leaves are also much thicker. Total height seems to be about the same, except for an eggplant. The one under the light (and growing in a hydroponics system) is double the size of the ones in the garden, though it was transplanted about four days later.
As soon as I get another 45 watt panel, I plan on germinating a tray of seeds and charting their growth over a 10 week period then comparing them to how other other lights produce. AJ has said he will try using shop lights with T12 fluoros, if anyone wants to use CFLs or HIDs your participation would be appreciated.
Mike