Something I have wondered as well. From what I found on the Internet, Adeniums use C.A.M https://en.wikipedia.org/wiki/Crassulacean_acid_metabolism

where the plant opens its pores at night to take in carbon dioxide, then closes them in the daytime to save water.

Well I looked up the weather in their native location. I have grown a few six foot plus plants in my grow tent using 18 hrs of light using about 500w of t5's.

I don't recommend it. If you went without sleep, you would die. If you only ate and drank but never excreted your waste, you'd die. They need a day/night cycle in order to remain healthy.

I run my lights 24/7 every single winter. Everyone here has recommended against it. They bloom all winter, and grow fine. Three years and running.

Check out this thread: https://www.houzz.com/discussions/what-are-the-consequences-of-leaving-lights-on-24-7-dsvw-vd~2006260

Thanks for your comments, right now I use 20/4 and I'm thinking to try 24/7 for a few days/weeks.

i keep the spare bedroom/plant habitat room cool …. 65 degrees and run lights 20/4 starting about now to wake them up ...

What do these numbers mean ( 20/4 , 24/7 ) ?

24 hours, 7 days a week (= all the time).

20 on and 4 off (per day)

And as Martin said 24 hrs a day/7 days a week

Charles basing on your CAM theory does that imply that foliar feeding will only be viable if done at night when the pores are open?

Never thought about that. I wonder if water and mineral intake is through the same pores that let in CO2 and let out O2. It could be, or the water and minerals might just permeate through the cell walls of the plant leaf.

jedobaTX9b says he has good results with 24 hour lighting, so I guess my idea doesn't hold water, or air, or anything else. I just was wondering. I have a lot to wonder about.

Edit: Wikipedia knows : https://en.wikipedia.org/wiki/Foliar_feeding

I am no plant expert in any way. I've been reading all of this posted information, and I must admit, that when I initially put my lights on full-time, I had different types of lights.

When I started, I used florescent with two small LED panels (very weak first-gen panels, and had only a few plants. Initially, my reason for always on was that florescent last longer lit full time.

While my plants seem fine, and bloom, I wonder if I am depleting some resources stored in the plant over the much longer times I have them outside. My plants are usually outside 9 months, and inside 3.

Most phyto laboratories run their lights at least 16 hours a day or more. Some do run them 24/7 with great results. Obviously it can be done without hurting most plants and they grow faster. So I think it's worth trying since others here already do it. I prefer to only have mine under lights in winter and outdoors when it's warm enough since I do not have enough lights of enough high output to compete with sunlight.