Many plants use this poorly lit season as a resting phase. They stop growth and bring down metabolism. Indoor plants prefer a slightly warm surrounding, while people usually like to have a very warm indoor temperature. For a lot of plants it is enough to place them further away from the heater. If you locate your plant in front of a window, you should make sure that it does not get a cold breeze. You also have to watch out that the leaves do not touch the cold window, otherwise the plant will get a thermal shock and its leaves will get brown and fall off. The root ball of your plant should neither stand at a cold nor at a too warm floor. Sensible plants will react with losing their leaves. Preventatively, you can place a piece of styrofoam, a cork tile or a plant dolly under the pot.