Color of light for gloxinias to bloom???

[Mama Bear]

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?

[beeky]

I see this sort of thing on my gloxinias that are outside in natural light so I don't think it is related to the amount of yellow in the light. I think the shriveling is caused by heat and/or low humidity. I have also observed that there seems to be a critical period during the beginning of bud development when the slightest lack of water will ruin the flower buds. Once the buds get to be the size of a pea they seem to be somewhat resistant to my poor watering.

--beeky

Mama Bear wrote:

[Mama Bear]

It may vary then, but in this case it's not dryness or lack of water. They used to bloom fine in the old house with some afternoon sun and in this one with winter sun.

[Steve]

Don't Gloxinias need to go dormant at some point? I grew some from seed (really, really tiny seed!) many years ago. I would grow mine for 9 or

10 months. Then they would start growing poorly and it was time to let them go dormant. I would let them dry and after a while the leaves and stems would dry leaving only the tuber (?). Two or 3 months later, I would see little fuzzy growths starting. I would bring them back to the light and water them. They would grow right up and bloom beautifully again.

Steve

[Mama Bear]

Yes, after mine bloom, the leaves droop and turn crummy looking. At that point I cut the whole top off and let them start over.

Yep, they're sweet little things. :)