SYRACUSE — Locally, gardeners are accustomed to using the soil to grow plants. There is another method of growing plants that is not so common locally, but is used elsewhere and on a global scale.
Wawasee High School students are learning about hydroponics, as well as aquaponics, in a unit of the advanced life science plants class taught by Joan Harden.
Hydroponics can simply be defined as growing plants without the soil. Aquaponics is the combination of hydroponics and aquaculture, or raising fish.
Beginning in the previous school year, students designed a tower system consisting of something similar to a long post sitting in a large bucket. The post has openings that protrude from it for the plants to be placed inside.
The plants are surrounded by clay pellets, noted student Gynnae Hochstetler. Before the plants are placed in the tower, they are grown elsewhere in the greenhouse and the roots washed off, she noted. The tower system is also located in the greenhouse.
From the bottom of the bucket water is pumped up through the tower and eventually falls back down. “We are hoping the plants will use the water,” Gynnae said. Plants being grown include tomatoes, green beans, radish and others.
“We are experimenting to see how you can grow things without the soil and how plants will take the hydroponics,” she said, and the project will run until the end of the school year.
For the aquaponics portion, students also designed a system in the classroom consisting of a fish tank on the bottom with plants in a container above. And above the tank and container are lights to help the plants grow.
Gynnae noted the waste from the fish is pumped and then filtered into the plants and it is hoped the nutrients can be used. Then the roots of the plants will provide some clean water to pump back into the fish tank. Plants being grown here include onion, pepper, lavender, tarragon and others.
Harden said hydroponics is not done so much locally or statewide because land availability is typically not a problem, therefore soil is used for growing. But in areas where the soil is not conducive to growing or heavy urban areas, hydroponics would be more common.
She was with some students at a conference in Indianapolis and heard a man from the Dow Chemical Company talking about a hydroponics experiment to grow corn in the Marengo Cave in southern Indiana and the yields turned out to be high.
Hydroponics tabletop systems can be purchased online and herbs and more can be grown in a home, Harden noted.
Students are applying biology and chemistry principles previously learned and are learning how to adjust nutrients as needed, as well as seeing the interactions involved in growing plants. “The students can actually see the roots and how big the root mass is,” she said.
And the students need to continually add water because it evaporates out of the system and fertilizer must be added too.
Learning about hydroponics and aquaponics began in February.