grow lights
What is the effect of grow lights on plants?
I know that if you have plants indoor, grow lights are supposed to provide what the plants should be receiving from the sun, if planted outside.
My question is, if I put grow lights on crops that are already planted outside (for example tomatoes), will this extra light have a good or bad result? perhaps reduce the time needed to harvest the tomatoes?
Theoretically, if you use grow lights on your plants at night, you could make them bigger, since they will be able to photosynthesize for more hours, gathering more energy. Foods grown far north, where there is virtually no night time this time of year, can grow huge.
As an example, the large vegetables that the hobbits were holding in the "Lord of the Rings" movie were grown in Alaska.
But trying to provide the extra light through grow lights on outside plants is pale compared to the photos provided by the sun. Plus - your electric bill, especially if you're doing more than a couple plants, would make the endeavor pretty expensive.
Might be interesting for a controlled experiment - but impractical for general production.
A look at what is currently available on eBay
 Grow Lights LED - lot of 2 US $50.00 
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 (2) 90 UFO LED Grow Lights 7:1:1 Hydroponic 660nm 630nm US $359.99
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 Quad-band 450 LED Grow Light Panel Hydroponic Plant Lamp Blue Red Orange White US $65.95
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