Good question. I'm not an expert but I'm prone to experimenting with adenium plants because I want to see the amount of neglect they will tolerate.

Adeniums are tropical so they don't really shut down the same way temperate plants do when it's cold and days are short. They slow way down though. If they are kept at around 15C to 16C, they lose their leaves but you'll notice they will try to put out leaf buds. If you keep them warmer than that, they'd still lose their leaves and try to grow. Without lighting, they'll etiolate.

Having said this, i've seen individual mature plants do strange things. I have one that has never gone dormant. I put it right against the window glass and it gets maybe 4 hours of sun there. In the basement, i've succeeded at coaxing two adults into some kind of dormancy for the past two winters. Both plants lose their leaves after about a month in low temperatures, even under LED grow lights. So I remove them from their LED spots and put one in some dark corner in the basement. The other one I put in a similarly dark spot upstairs where it's warmer. Two weeks later the one upstairs has leaf buds on every tip. This year, I switched and still, the one upstairs just went back to growing when it got warmer.

That sounds to me like they respond first to temperature and only second to light.

Since these two are mature plants i just leave them unlit. If they insist on growing, I prune them in spring.

The other thing I was planning to do this winter was to prune one or both of these plants to remove the growth. Then just leave them in the closet or something. But they dropped their leaves first before I got to them. I guess letting them get cold was enough.

Seedlings less than two years old are a different matter, though. If you do not want to bother providing extra indoor lighting, don't sweat it. They'll probably etiolate but so what---just prune them in the spring if you want to keep them compact. And do not fertilize them much if they are getting very little light---they'll just grow weak, lanky branches.

Pagan

Pagan-

Thanks for the cultural details, and for the interest. All this Adenium growing is still a big mystery to me. However, with all the expert help from forum members, I think I can keep my few plants alive until the warmth and sun return to NYC....hopefully.

Frank