It has been my experience that braod spectrum flourescents are adequate
(Your normal, every day flourescent) as a supplemental light. It is also
my experience, however, that supplemental lights should only be used in
conjunction with daylight. Extending the "day" with artificial light
screws up the plants natural cycle, unless it is done "scientifically" for
a desired effect. (It can inhibit flowering.) My solution is to match the
right kind of plant with the available light.