John Thomas wrote:

For what it's worth, Scientific American had an amateur scientist column
c. 1969, since reprinted in collection of the columns, on what sort of
lights work best with seedlings and mature plants.

I have been taught by the experts that the "gro-lites" are a waste of
money. The best grow lights are a mixture of cool white and warm white
fluorescent tubes. On a 2 tube fixture, use one of each. On a 4 tube
fixture, alternate with 2 of each. This combination the highest lumens
per watt and spans the optical spectrum best.
--
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