|MadSci Network: Botany|
If you use one or more 4 foot long shop fixtures with cool white fluorescent bulbs you should get substantially more light than natural sunlight on a windowsill at that time of year. Run the lights 16 or 18 hours per day to maximize light and keep the top of the plants a few centimeters from the bulbs. The cool white bulbs are low in far red wavelengths so plants are often a bit shorter than with sunlight. That is usually an advantage because seedlings grown indoors tend to get overly tall. The lights also provide some heat which can speed growth. Reference Hershey, D.R. 1995. Plant Biology Science Projects. Wiley: New York.
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