Light level for Phalaenopsis

[Havoccity]

Specifically for Polychilos. I know that most Phals can bloom well under "low" light conditions. But would they bloom better under high light conditions (burning aside)? I've read conflicting info on this; I sometimes hear that too much light is detrimental, but I've also heard (eg, from Dimitri Ravot) "to push the light as far as it will go" for Phals. For now I'm growing a bellina directly under the light. Its growing well vegetatively but I'm wondering if the brightness could negatively affect blooming.

[Dimples]

Some people suggest moving phals to lower light (~1000 foot candles) once a spike has initiated and grown a bit. I don’t have the room to move mine around like that, so they get what they get, and that’s usually long duration natural daylight from a south/southeast facing bank of windows. The phals get ~2,500 fc at peak intensity and they all bloom well. I wouldn’t worry about it too much.

[Ray]

Such phals are deep understory plants that live in deep shade, with some, but minor wintertime light increase due to the loss of leaves by some of the deciduous trees making up the canopy overhead.

As the chemical reactions that occur within plants are significantly affected by temperature and light levels, and if we accept that these plants have evolved to function optimally under those conditions, it seems logical that forcing them to grow under constantly higher light levels would be counterproductive.

I have found that to hold true with my own plants, with those grown constantly shady producing spikes carrying more flowers that last for longer time periods.

That said, if you’ve been growing brighter and decide to shift the plants to shadier conditions, be prepared for them to take some time off from blooming so that the chemical balance can be reestablished for the new conditions, but when it “comes back”, the show will be superior.

[Dalachin]

Most Phal hybrids seem very tolerant of different lighting conditions, as long as their leaves don’t burn. However there is a pool of different genes from different Phal species in these plants, and they can have different needs— some may bloom under low light, while others might need higher light to bloom regularly. Personally I’ve found little downside in giving them pretty high light (led) as long as the plants are not showing stress. If you grow Phal species, some of these species preferences show up more strongly, for example I have a Phalaenopsis celebensis that struggled until I gave it a shady place.

[estación seca]

Eric Goo in our orchid society bred Polychilus Phals. for many years, and received many awards. He is adamant about not going above 1,000 foot candles except perhaps for a few weeks in late Fall. You can read the notes I took from speaking with him in the forum Phalaenopsis - Hybrids. It's a sticky thread near the top.