If you’re one of those folks lacking a green thumb, space and time for a garden, a researcher and a teacher on the Big Island have an answer for you.
It’s the best hydroponic system with everything needed to grow plants without dirt.
“You can get yourself a nice little hobby and something you can eat,” said the inventor, horticulturist Bernard Kratky of the College of Tropical Agriculture and Human Resources, University of Hawaii-Hilo.
J. Patrick Sager, a ninth-grade physical science teacher in Hilo High School, uses the kits to teach chemistry and mathematics.
Sager has established a company, Home Hydroponics Systems, to market the kits. He hires high school students to assemble them. Right now it’s a “garage business,” but he’s building a new home with greenhouse facilities.
The UH has received a patent for the kit and the UH Office of Technology Transfer and Economic Development grated a license to Sager to make and sell the kits.
A percentage of all sales goes back to the UH for research, Sager said.
Kratky, who looks for better and cheaper ways of growing vegetable crops, said he got the idea during a 1985-86 sabbatical leave in Taiwan.
“My boss there started work on hydroponics. I got interested in it because it solves some of problems we have here in Hawaii-soil- related problems, the worst of which is not having any.”
Other gardeners battle soil diseases and nematodes, requiring chemical control methods, he said.
The kit basically is a floral tube, 8 inches long and 1-1/2 inches in diameter, with extra holes drilled into it, he said. Potting medium, seeds, pre-measured plant nutrients and instructions are included.
He originally planned to have a bucket and lid in the kitchen, then decided buckets are hard to move and bulky to sell and most people already have them.
“So we made sort of a universal lid, about 1 foot square. It fits anything from a 3- to 5-gallon bucket. Also, it’s good if you have an aquarium,” Kratky said.
“You can grow fish in the bottom and lettuce or a crop on the top.”
Sager said beans grow well in kits atop aquariums. “I have them growing at school–beans crawling up trellises. Fish swim around on the roots.”
Now he’s looking for food the fish will digest to refertilize the water and re-nutrify the plant.
Kratky pointed out that traditional hydroponics involves circulating or aerating water, which requires pumps and electricity. His kit does not needs any of that.
Just fill a bucket two-thirds with water so the bottom inch or two of the tube, held by the lid, is in water, he said.
In the case of lettuce, he said, you put a couple teaspoons of special blended hydroponic fertilizer in the water, mix it a little and walk away from it until it’s ready to harvest.
The kit must be placed where it gets sun and no rain because rain raises the water and level and drowns the plant.
The kits are ideal for classrooms, Kratky said, because no one has to worry about watering on weekends.
Sager uses the kits to show students how plant food breaks down into elements.
He said he teaches students about volumes and circles because there are a lot of water catchment systems in the Hilo area. They learn how to calculate water so they can calculate it in their tanks at home, he said.
“It gives them reality-based science. And they can eat their experiments.”
Kratky said several commercial growers are using the system to raise gourmet lettuce and other vegetables.
With sugar plantations closing on the island, alternative agricultural enterprises are needed, Sager said.