I give mine bright, indirect Sun. Not sure about your light set up, I'll let someone else comment on that.

I'm not sure whether you can get a really good blooming Sharry under HIDs. I have HIDs and in fall when they are on, it is very hot down there. It doesn't really cool off in the light room until the winter has set in.

Just not sure that several months of daytime highs of 95= is the way to bloom them. They might set spikes in winter after it gets a lot cooler. Also, the plants tend to be tall, so the lights are at least 2 feet away, maybe more. Light drops to 1/4 that at the source at a distance of 2 feet. So could be not quite enough light for a lot of blooms.

But I've gotten many, many spikes on mature Sharries, that bloomed on over more than 6 months by the simple expedient of keeping them outside in late summer and fall as the days shorten and the cooler weather comes on. I got the best bloom of all the year I kept them out until the temperature went well below 40 in late October. They burst into bloom almost the minute they were brought indoors. At least a half-day of sun.

Sharries can bloom at other times of the year, but the orgy of spike setting is in the fall. Either long nights or cold nights seems to stimulate the spikes. Worth a try if you have a spot to set them out in.

Your temperatures should not be a problem. I grow hundreds in Florida heat and it has been pushing 100 all month. Even winter is in the 70s. What happens in high heat is the plant protects itself by growing shorter leaves too conserve moisture. Forida Onc will be 20% smaller than those grown on Hawaiian mountainsides. They still flower well.

Inadequate light is probably the problem. They need 2500 foot candles of light to set buds. Phals set buds at 1000-1500 so you can easily get good blooming phals and no Onc.

mehitabel was correct in suggesting setting them outdoors in the fall. It gives the lower temps, shorter daylight hours, and more light - all genetic factors in blooms. Once the spike starts the light level is no longer important and the buds will open and flower back inside.

Your Dens and mini-cats need even more light about 3500 foot candles of light. Inadequate light is the reason for 90% of hobbyist's failure to bloom.

I did put in a fresh HID bulb and it's a lot brighter, and I also added some shelves to get the plants closer to the bulb. But I don't think I'm at 3500 footcandles. Bummer.

I never grew Dens under my HID light but I did grow catts and got them to bloom. You are correct the fc's aren't 3500 but you run the lights for an extended time to make up the fc difference.

Brooke

I have seen a number of views that lights are more constant than daylight and the numbers for flowering can be less with artifical lights.

It would be an interesting experiment.