New life is springing from Albuquerque’s recycled materials.
A new partnership between the city of Albuquerque and Growstone, a subset of Santa Fe-based company Earthstone, has landfill glass waste being turned into a hydroponic gardening tool.

“Glass makes up about 8 percent of municipal landfills,” said Patrick Beare, Growstone’s vice president of sales. “And it takes about 4,000 years for glass to decompose on a landfill.”

The city of Albuquerque landfill pulverizes glass bottles, which Growstone then grinds to a powder and runs through a kiln, said Andy Hernandez, Earthstone director of operations.



“Seventy-one minutes later it comes out — it’s like baking a cake!” he said.

Hernandez said the growstones are cut from pieces of baked powder to form hydroponic stones that are used in place of soil.

“The roots of the plant actually grow around our material,” he said. “What happens is our material absorbs the water and when the roots get thirsty, they draw from our material automatically. What that means is less water, and more consistent water, but no soil.”

Maria Colbert, an Albuquerque Hydroponics representative, said the store has carried Santa Fe Earthstone products for two years, and they are useful.

“They hold a lot of moisture as well as they are really airy. For people who want to use it as soil, you can use it instead of perlite. It has got multiple different uses that you could utilize it for,” she said. “They are a local product. The people that are trying to support that — it definitely helps out.”

Beare said the company foresees the product becoming popular in the future, as it is one of the first hydroponic growing media in a long time.

“A lot of people think that just because they put glass in this recycling bin that it is actually being made into something else, and that is not always true,” he said. “We are able to take this glass and use it and make it into a product that you can actually grow things from.”
Beare said glass is difficult to recycle because it has to be sorted by color.

“We as a country only recycle between 28 to 34 percent of the glass we produce,” he said. “Many cities will only sort out the glass because it takes up so much room in a landfill that they crush it and then bury it. It takes clear glass to make a recycled clear jar.”
The stones have benefits over soil and other hydroponic mechanisms, Hernandez said.

“Our material is so lightweight,” he said. “It weighs 12 pounds per cubic foot, so it can be used on rooftops and high-rise buildings. We had several tests done at the University of Arizona versus our competitors, and what they found was that our product uses less water and provides a sweeter fruit.”

Beare said Growstone has plans to process other landfill waste.
“Eventually we will be using the methane that is being produced from the landfill to run our kiln,” he said. “Also, we don’t use water to produce our product. It is a dry process, so that is another reason why our product is so green.”