Along with light and water, humidity is an essential component to grow healthy and thriving house plants. In general, most house plants need a relative humidity of 70 to 80 percent, which is hard to maintain in a home, especially during the winter months. Fortunately, there are many techniques that help increase humidity. While one method may be sufficient, often several methods may need to be combined to increase humidity to the ideal levels.
Group house plants together since plants let off water vapor. The more plants that are grouped together, the higher the humidity in the area.
Put pebbles in a tray of water. Set the house plants on top of the pebbles and refill the tray with water as necessary. The water will evaporate and increase the humidity. Do not set the house plants directly in the water, which will cause your plants to absorb too much water and could lead to rot.
Place your house plants near the kitchen or bathroom where humidity tends to be higher. On the other hand, keep the plants away from fireplaces, wood stoves and other dry heat sources.
Run a humidifier. Alternatively, put pots of water on your hot stove or radiators. The heat will cause the water to evaporate into the air which will increase the humidity.
Turn down the heat. Higher heat usually means lower humidity.
Mist the plants. Do so sparingly since moist leaves can lead to fungi growth. Plants in a sunny area can tolerate more misting--especially in the morning--since the leaves are more likely to dry.