What Type of Water Is Best for Watering Plants?

Room-temperature water is best for plants.

Water softeners, which replace the magnesium and calcium in your water with sodium, are bad news for plants. Magnesium and calcium are essential nutrients for plants, whereas high levels of sodium in plant soil may cause brown leaves and damaged roots.

Source

The best water for plants is natural, untreated water. Rain water, melted snow or pond water are all excellent choices. In the absence of these, water from your tap is an acceptable option for most plants, provided it has not gone through a water softener.

Temperature

Whatever your water source, let water stand until it reaches room temperature before watering plants. Water that is either too hot or too cold could damage your plants.

Misconception

Houseplants suffer more injuries and fatalities from improper watering than any other factor. However, they are usually related to the amount of water plants receive rather than type of water. Excessive watering and insufficient watering may both result in plant roots dying.

References

• University of Missouri Extension: Caring for Houseplants; David H. Trinklein; April 2010
• North Carolina State University: Watering Houseplants; Erv Evans
• University of Minnesota Morris: Soft Water for Houseplants; Feb. 2005
• Penn State Cooperative Extension: Houseplant Care in Winter; July 2009