Well, it's NOT simple. Because even the ones sold commercially don't seem to work.
Yeah, it is that simple, because I've done it along with a lot of other people :huh: Once it again it seems we're basing technology on the basis of what's available shipped from China in container ships.
I've talked to the "hydroponics" shops in town.
I'll give you the skinny on these guys because I did the same thing and was also greeted with the same attitude. However, some dude making $8.50 an hour at the local hydro store doesn't qualify as a pinnacle of science in my book.
Hydroponics stores are
retailers and in the business of selling products, and make nice mark-ups on old tech growth engines. These guys still think full spectrum fluorescent bulbs are the highest tech growth technology, etc. One actually still preferred Vita-lights. Mine actually do sell UFO lights and other stuff, but only because over half their business is a nudge-nudge-wink-wink towards dope growers.
One thing I do agree with them about is these hydro guys tend to prefer linear lights over dense panels, and high powered linear LED growth lighting has only just recently been getting popular. Pretty sure Photowave was working on a product like this. I also build insanely high powered rails, but only for friends and legit purposes.
So, don't expect un-biased comments from hydroponics stores because they want to cater to their market which isn't exactly above ground. They sell products.
All of these panel type LED products discussed here are pretty much orientated towards dope growers, which explains their color ratio and tightly packed LEDs. Not exactly something that would work well on a row of houseplants against a wall or on your counter. Fluorescent fixtures do work better for this, and you don't have to worry too much about R/B ratios because a plant will take what it needs from a white light source.
Otherwise, fluorescent lights sources aren't neary as efficienct as narrow band light sources like LEDs or HPS when it comes to growth radiation, and using 'lumens' as a measurement is bad because plants don't care about visual lumens or green light. Basic science, and we've bantered it in depth here and it's been proven by NASA research, etc. You could probably get away with half if not less energy used with LEDs than T5's to grow anything, but the difference between 30watts of fluorescent -vs- 15 watts of R/B LED just doesn't matter to most people. Plus, the purple glow of +20watts of R/B LEDs gets to be annoying after awhile. I did this over the winter with various houseplants and huge amounts of red light, and after awhile even my cats got sick of it. Plants however grew at insane rates. Faster than sunshine.
When it comes to big agriculture these guys use Metal halides and HPS, and that's pretty much it. Dope lights don't do it for them, and they are really skeptical of LED given it's rather narrow 'vocational use'. They do have a valid gripe, but for the wrong reasons. Blue light just isn't that critical a light source and comes from pretty much anywhere. Longer wavelengths required for fruiting, veggies and stem length are handled by 400 or 1,000watt HPS, and even though LEDs pump more energy at 630 or 670 nm, it's just not practical trying to replace that big a light source with red LEDs. If I were to design a green house from the ground up I'd certainly use low flying LED rails though, and my power bill would be less.
