You can indeed bring it indoors, if you have room for it in a sunny window.

Trim it back to a reasonable size, realizing that it will likely grow during the winter, although not as rapidly.

Clean it really well before bringing it inside. I have found that they are susceptible to aphids, and/or white fly. Hose it down really well; spray with an insecticide of some sort including the top of the soil; let the insecticide do its thing for a few hours; and then hose it down again. I would also let it dry in the garage before you bring it inside.

Ihope it works for you. They are a beautiful plant.

Yes, the only times I have not succeeded is when I did not get it cleaned well enough & eventually lost it to infestation. Other years, no problem, did not even keep it in a south window. Good luck.

So how's the mand. doing lary?

I brought my mandevilla in over winter and it doing great, want to try to get some starts. also brought my gerba dasies in and have a fungus gnat problem. Any suggestions on getting rid of them.