How Often Should I Water a Boston Fern?

The Boston fern (Nephrolepis exaltata) makes a good indoor house plant or can live outdoors in U.S. Department of Agriculture hardiness zones 9 to 11. Like most ferns, it loves wet, boggy soils and high humidity.

Curling and browning fronds indicate a water deficiency.

Watering Needs

Water the fern when the soil becomes damp. Do not allow the soil to dry out. This may mean watering twice a week or daily in hot weather. The frequency will change depending on the temperature and moisture in your home. Add enough water so that it flows out the drainage holes on the bottom of the container.


Boston ferns require a high degree of humidity to thrive. Place the container in a bowl filled with rocks so that it rests on top of the rocks. Pour water into the bowl to increase humidity. Mist the fern daily, using a water sprayer, to keep the humidity high.


If a Boston fern isn't getting enough water, the tips of its leaves will begin to turn brown. Increase the frequency of watering and mist the fern fronds daily to protect against browning leaves.