Living in a non-tropical area such as I live in, where there is no humidity and 3 feet of snow on the ground during winter, I had to think of some way to keep my tropicals actively growing.
So, on a forum I frequent I was told by a member that aquariums are great for holding humidity and higher temperatures. I decided I would give it a try.
I set up an aquarium next to a big bay window. I placed an ultrasonic humidifier inside of the tank and covered the top with plastic. I had a problem with water that would accumulate on the bottom of the tank due to the humidifier. I then placed gravel on the bottom of the tank so that the water was no longer a concern. And of course, there is a light on top of the tank with a warm and cool bulb.
The trees grow non-stop. They also push aerial roots like crazy. Look in the photos section for pictures of the technique.