To answer several questions we’ve received on grow-lights, I will combine several points into one article.
1. There are many opinions on what kind of lights to use, but based on research and experience, it is apparent that plants will do well under a variety of tube combinations, with the best results probably coming from a combination of one warm-white, and one cool-white or daylight tube in each fixture.
2. Buy shop lights with cords already attached. The cost difference is almost nothing, and you don’t want to be doing electricians’ work for several reasons. Use a #12 or #14 (heavy gauge wire) extension cord and 6 outlet surge bars, to give you enough plugs and power capacity.
3. The ideal distance lights should be from the plants has been said to be everywhere from 1/2″ to 6″. I recommend you maintain the lights very close to the seedlings (1-2″) to maximize the light intensity. Since fluorescent bulbs give off very little heat there is no danger of burning the tender leaves.
4. Use 2 sets of shop lights for each shelf, giving you 4 bulbs totaling 160 watts. A 4′-long shelf can provide light for 4 10″ X 20″ plastic trays. Move the trays around and turn them front-to-back regularly, to assure even light distribution to all plants.