Pay Attention to Temperature
Most plants, like people, are comfortable in daytime temperatures between 65 to 75 degrees F. and nighttime temps above 50 degrees F. To provide that for your plants, keep them away from both cold drafts and sources of heat, like radiators, ovens, fireplaces and electronic devices. Fluctuations in temperature can be just as damaging as prolonged periods of heat or cold.
Low Humidity
Low humidity is probably the biggest hurdle to overcome during winter. The humidity level in heated homes can drop to 10 - 20% in winter and plants prefer a level closer to 50%. If you have a humidifier in your home, move your plants to a spot where they will enjoy its benefits. If you do not have a humidifier, you're going to need to raise the humidity level by other means.Start by clustering your plants in groups. Plants naturally release water through their leaves by transpiring and grouping them together will put that moisture to good use. If you have room in the bathroom or kitchen, these are the best rooms to congregate your plants, other than the one with the humidifier in it, because they accumulate the most moisture from showers and boiling water.