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The Effects of Tap Water on Plants

Whether pumped from treatment plants or pulled from a home well, tap water can contain a range of contaminants that harm plants. Watch for signs of impure tap water to prolong plant life and promote stronger growth.


Tap water with excess salts can prevent roots from absorbing enough water and nutrients. Tap water treated with chlorine and fluorine produces leaf spots, singeing and curling of leaf edges.


Plants poisoned by tap water may die very suddenly after many months of apparent good health.

Other Indications

The formation of white residue on soil, leaves or clay pots indicates the use of tap water with too much salt.


Tap water from home wells may be softened to reduce mineral content, introducing many salts that will injure roots and leaves.


Gardeners can remove some harmful chemicals from tap water by allowing it to sit for a day before being used.


Some plants are susceptible to being damaged by water that is too hot or cold. Only water plants with tap water that is close to room temperature.

Effects Of Tap Water On Plants

House plants need two basic things: water and light. The best water for your plants is free of impurities such as minerals and chemicals. For many people, straight from the tap is fine. Others have tap water loaded with minerals or chemicals that can harm plants. Use clean, empty milk jugs or soda bottles to hold the water while it "breathes." These minerals are bad for your plants, so you shouldn't use hard water directly on them. You also shouldn't use hard water that's been run through a household softener; the salt used in softeners is also bad for the plants. This is visible as a thin, whitish crust on the surface of the soil. If you get this buildup, flush your plants once a year. Far more houseplants are killed by over-watering than under-watering. Stick your finger about an inch down in the soil.

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