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What Are the Benefits of Rain Water When Growing Plants?

By Lisa Dorward
Rainwater: health food for plants.
Image by Flickr.com, courtesy of John Morgan

It’s not an old-wives' tale; rainwater really is better for growing plants than water from a hose. What makes rainwater better is not just what it doesn’t have, such as harmful chemicals and treatments, but also what it does have: vital nutrients.


Evaporation of ocean water forms clouds.
Image by Flickr.com, courtesy of LASZLO ILYES

Rainwater is formed by the evaporation of the oceans and inland bodies of water. When the moisture condenses, it collects sulfur, which is essential to the formation of plant amino acids.

Essential Elements

Rainwater makes photosynthesis possible.
Image by Flickr.com, courtesy of Anita Martinz

Rainwater is high in nitrogen, a key constituent in chlorophyll, the greening ingredient essential to the production of carbohydrates through photosynthesis.

Chemical Process

Lightning plays an important role.
Image by Flickr.com, courtesy of Ethan Hein

When lightning strikes during a rainstorm, it causes nitrogen in the atmosphere to combine with hydrogen, creating an important fertilizer for plants that is then carried by the rain into the soil.

Other Processes

The miraculous process of rain.
Image by Flickr.com, courtesy of Bùi Linh Ngân

Rainwater captures the dust carried on air currents and delivers it to the soil. This dust contains important minerals and microorganisms that contribute to the breakdown of organic compounds into plant nutrients.

The Alternative

Tap water: fast food for plants.
Image by Flickr.com, courtesy of Donald Macleod

Tap water contains salts, chlorine, fluoride and other chemical treatments that are harmful to plants.


About the Author


Lisa Dorward was a corporate financial executive and business consultant for more than 15 years before becoming a writer in 2003. She has B.A. degrees in both history and creative writing and earned her M.F.A. in creative writing in 2008, specializing in novel-length historical fiction.