Water Quality and Plant Growth
Water Quality and Plant Growth is how the stuff mixed into water changes the way plants grow.
Salt added to a glass of water changes how a plant grows in it. Tiny salt particles crowd the water and block the roots from drinking. Clean water has fewer particles, so roots can pull it up easily. More particles in the water means less water gets into the plant.
Explaining water quality and plant growth by grade level
Plants need water to grow. Clean water helps plants grow big. Dirty water can make plants sick. Some water has things in it that help plants. Some water has things that hurt them. You can test this with seeds and cups of water.
Projects that explore water quality and plant growth
Stuff mixed into water can hurt plants. Detergent adds harsh chemicals to water. When plants get this water, they can die. This project shows what happens when you water plants with detergent mixtures.
Different water sources contain different dissolved substances, and those substances change how plants develop. Tap water, mineral water, and seltzer water each deliver a unique mix of minerals and dissolved gases to plant roots. In this experiment, seltzer water produced the tallest radish plants, while mineral water produced the heaviest, showing that what is dissolved in water shapes both height and mass.
The mineral content of water does not always change plant growth — but it's worth testing. Hard water has extra calcium added to it, while soft water has minerals removed by a water softener. This experiment places 20 black-eyed Susan seeds on cotton in each of three beakers and tracks how many germinate each day over five days. By the end, the totals are nearly the same across all three types of water.
Recycled water may carry dissolved minerals that act like mild fertilizer. This project compares radish growth across distilled, tap, and recycled water over four weeks.