Now that the days are shorter with much less daylight, how much advantage is there adding supplenental lighting over the growing benches. How much light is needed and for how many hours? Each bench is 4' X 10' and there is three of them. Will a two tube fluorescent fixture over each bench be enough? How much will it shorten the growing time? Thanks for the advice
The answer to this depends greatly on where you are at and how much light you are getting. Obviously the more like you get with lettuce the better, but the cost benefit of supplemental lighting comes down to:
1.) How much natural light do you get? To see a map that gives you a general idea of the available natural light outside check out...http://www.extension.purdue.edu/extmedia/HO/HO-238-W.pdf
2.) Then figure out how much electricity cost you.
3.) Then look for the most efficient light sources you can find.
4.) Then determine how much "light" you want to make up for the day.e
5.) Then determine how much that will cost you based on the amount of time you need to run your lights.
For sure lighting will provide you an advantage. Lettuce loves light! The question is what is the best for your business. Good luck.