This is a question that comes up quite a bit. “Can I run my LEDs 24/7? Won’t that give me more growth” or “Can I leave my lights off during the day because I have supplemental lighting and run my LEDs at night?” These are pretty much the same question. What is really the question is “Can I have my LEDs on during the night?
First we need to look at orchids and their physiology. Orchids do their photosynthesis during the day. However the unique thing about orchids is that they complete the photosynthesis process over a 24 hour period. That is they are photosynthesizing during the day, but their stomata (the mini pores that allow the exchange of gasses between the leaf and the atmosphere) only open at night. So while the orchid is photosynthesizing during the day it takes the night cycle to complete the process. During the night the stomata open and oxygen is released and carbon dioxide is taken in.
Leaving the LEDs on 24/7 or only at night can interfere with the completion of photosynthesis. I would NOT recommend leaving your LEDs or any other lights on for your orchids at night.
What I do recommend is like I have said in my “Smart Plug” blog is to put them on a smart plug and run them from morning to night. Or a set amount of hours like 12-16 hours and then have the smart plug shut the lights off. In my opinion this will give you optimal benefits while not stressing your orchids. Happy Growing!