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LEDs and Vegetative growth
Kenny

I own a 90w UFO, my experience with it: I am not convinced, I am using it 16 hours a day as a supplement light (2 feet above my plants) in my solarium, I am living in Ottawa, Canada, the days are short and dark. Two months passed, I didn't see any improvements on my plants at all. I mean not at all with or without the LED. The plants are simply blind to the lights.

Then I moved some plants down to my basement with a MH light bulb, they exploded with new growth. One of advantage the LED vendor rave about is the no heat, well I think plants need the warmth to grow. The leaves need the vaporation.