Going Green?: Will plants watered with greywater containing an environmentally friendly detergent be healthier than plants watered with greywater containing a conventional detergent?
Clare Sully-Stendahl
Stratford Hall
Floor Location : M 232 L

Greywater is used by many households as an environmentally friendly way to reduce water consumption. Greywater is water collected from locations around the home such as showers, baths, sinks, and washing machines, and is used, among other things, to water plants. One of the most common places to collect greywater is by removing water from a washing machine. However, this water does contain laundry detergent, which may or may not affect the health of the plants watered with it. This experiment tested whether Polka Dot plants are healthier after being watered with greywater containing an environmentally friendly laundry detergent, such as Seventh Generation, or a conventional laundry detergent, such as Sunlight. There was also a Control group of plants being watered with tap water. It was hypothesized that the plants being watered with the Seventh Generation detergent mixture would be healthier than those watered with the Sunlight detergent mixture, but this hypothesis was proved wrong. The Sunlight group of plants were much taller, and had more leaves, than the plants in the Seventh Generation group. This is largely credited to the fact that Polka-Dot plants prefer a more acidic soil, and the Seventh Generation laundry detergent was more alkaline than the Sunlight laundry detergent. This created a more alkaline soil for the plants in the Seventh Generation group, thus affecting the overall health of the plants. Though the Sunlight plants were almost at the same level of health as the Control group, the Control group ended up faring the best, according to hypothesis.