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"Many forms of plants".... yeah, right (LOL!!!!)

I estimate this to be the equivalent of a 15 watt HID light. Which won't do hardly anything.

A 300W HID outputs:

- 80% infrared heat (not helpful for photosynthesis)
- 10% green / yellow (reflects or is weak photosynthesis)
- 10% red / blue (primary photsynthesis)

That means maybe 30W of energy is usable to plants isn't a standard white grow light. LEDs change the game. NASA has been researching this for over 15 years. You will find dozens of white papers saying the same.

There are many ways to grow fuel, food, and drugs. Using efficient LEDs is a better way than standard grow lights.

I've been growing peppers and cucumbers with LED lamps as part of my experiments to find the perfect spectrum (or rainbow as some call it) for plant growth. With the current power of LEDs, I'm not sure we can make say that 30 watt of LEDs = 300 watt HID. I would say it will be there in 2-3 years as efficiency keeps on improving. My current lamp prototype is using 60 watts. And if you look at the smart lamp from Theoreme Innovation, they compare their 275 watt LED light with a 600 watt HPS (http://www.theoremeinnovation.com/revolution-en.html) but their spectrum is too limited in my humble opinion and those who experimented with it.

Best advice I can give you : YOU NEED WHITE LED TOO (warm white is better) ! even if a plant maximize the usage of red and blue light for photosynthesis, it's not the only function mediated by light in a plant. A plant still need some green, yellow, orange and far red light to be healthy. Without some "complete spectrum" complement, most plants will have a lot of problems grown only under red and blue.

Also keep in mind that by only using the standard "hi power" red led at 625nm, you're missing the 660nm required for phytochrome (mediator of flowering and other functions). Some warm white LED will provide that missing part of the spectrum in the red / far red or you can also add some 660nm. Since a good part of the output of white LED is also in the blue spectrum (The main source of a white LED is a blue LED with phosphor coating that "down convert" part of that light to other wavelength), you could simply replace some blue LED with white one. And it's usually in the 455nm, very important for cryptochrome (if you are only using 470nm light, you might have an etiolation problem, both 455 and 470nm are important). Cree white warm (mounted on star) are a good choice, and I would add some cold white in the mix. If you're looking for 660nm power LED, the only suppliers I found so war is Eddison in Taiwan (they produce 1 watt 660nm LED in a "luxeon package") and Norlux with their HEX 660nm (my choice so far).

That's my 2 cents. Good luck with your experiments !

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