We're in a house now where the sun only comes into the plant stand area in
the winter. So 6 months a year they depend only on the grow light above.
I just got a nice new fixture with 3 T8 32 watt tubes instead of the two
40 watt T12's that used to be there. They even have a polished mirror
reflector, so they put down even more light. But the tubes I got with them
are purplish grow light tubes and the gloxinias are forming buds now but
then they shrivel away and don't bloom.
I think someone here awhile back was saying that these kinds of plants
need yellow to bloom? Should I replace one ( or two? ) of the grow lights
with a T8 warm white, that has yellow?