Marc Debnam/DigitalVision/Getty Images
Plants can be picky about the nutrients they consume to grow. Plants rely heavily on water, as you know if you've ever neglected to water a plant. Not all water sources have equal benefit for plants. Different plants may also have different specific water requirements to grow well. Rain water has some advantages over tap water for some plants.
Chemicals in Tap Water
Tap water contains ingredients added as softeners, such as sodium, or for human health, such as chlorine or fluoride. While most plants tolerate tap water, fluoride may injure plants with long, slender leaves, such as the spider plant. Leave fluoridated water out overnight at room temperature to let fluoride evaporate before watering plants, horticulturist Erv Evans of North Carolina State University suggests. Do not use softened water for watering plants, he also suggests. Excessive salt in the soil prevents the roots from absorbing water. A moderate sodium content of less than 200 milligrams per liter will probably not cause harm, the Water Quality Association reports.
Filtered or Distilled Water
Reverse-osmosis filtered tap water, deionized water or distilled water will not contain the chemicals that could interfere with your plant's growth, making them a better choice than tap water for your plants. You can buy distilled water or make your own by leaving tap or rain water in a clean container for two days before using it, which allows the chemicals time to dissipate.
Rain Water and Acidity
Rain water doesn't contain added chemicals such as sodium that can damage your plants. However, rain water can be more acidic in some regions than others. Contact your local extension service or university horticultural department if you are concerned. Very high acid content can damage plants. As long as your rainwater isn't overly acidic, collecting rainwater in a clean bucket or barrel gives you a good and cheap supply of water for your plants.
No matter what type of water you use to water plants, use it at room temperature. Water straight out of the tap may be hot in summer and cold in winter; either extreme can shock the plant roots. For potted plants, use containers that allow excess water to drain, since standing water can damage the roots. Don't over-water. Over-watering actually kills more houseplants than under-watering, according to the Guide to Houseplants. The soil should not be soggy, just slightly moist.
Alternate Ways to Divert Roof Rain Water
The Effects of Organic Fertilizer on ...
Why Should You Use Filtered Water in a ...
The Calcium Content of Spirulina
Why Does the Hair Fall Off of Your ...
4 Different Ways to Use Water Wisely at ...
How to Use Sea Salt for Canning
How to Store Contact Lenses Without ...
How to Cook Mixed Greens
Can Peanut Shells Be Used for Compost?
Potassium Permanganate to Wash ...
What Are the Benefits of Water ...
Does Canned Soup Go Bad?
Are the Nutrients Lost in Slow Cooking?
Nutritional Value of Dehydrated Green ...
How Do I Clean Water Cress?
What Happens to the Alcohol ...
How Much Water Should I Drink With a ...
How Long Does It Take to Steam a Yam?
How to Gargle With Sea Salt
- North Carolina State University: Watering Houseplants
- Water Quality Association: Should Softened Water Be Used for Watering Houseplants or Sprinkling the Lawn or Garden?
- Washington University in St. Louis: Acid Rain
- University of Missouri Extension: Caring for Houseplants
- Guide to Houseplants: Watering House Plants
A registered nurse with more than 25 years of experience in oncology, labor/delivery, neonatal intensive care, infertility and ophthalmology, Sharon Perkins has also coauthored and edited numerous health books for the Wiley "Dummies" series. Perkins also has extensive experience working in home health with medically fragile pediatric patients.
Marc Debnam/DigitalVision/Getty Images