Bay Shore, N.Y. ? In one area of their landscape recycling yard were pile upon pile of mulch, much of it being dyed black, red and brown. In another area were piles of crushed concrete and asphalt. Much of it was, well, doing nothing but piling up.

“We saw this demand for landscape mulch,” says Billy Zorn, who, with his brother, Michael, runs Hubbard Sand & Gravel, a landscape and mason supply, and North East Recycling. “We were dyeing it and seeing it go out of the yard almost as fast as we could get it ready.

“And we kept thinking, ‘What can we do with the crushed aggregate, the concrete? Is there something we can do to make it popular as a ground cover, like mulch?'”

After nearly five years of research and development, the Zorn brothers finally have their answer. It’s Zorock decorative stone, a color-rich, manmade landscape cover that’s making noise in warm-weather climates such as Florida and a few other Southern states.

The Zorn brothers say they believe Zorock, made from recycled material, can replace mulch in many landscape applications. For one, Michael Zorn says, it’s nontoxic. Also, it’s taking a waste material and making it a colorful, long-lasting product. “Children or pets could get a rock in their mouths, and the coloring won’t harm them,” he says. “And unlike mulch, which has to be replaced every few years or even sooner, Zorock lasts and lasts.”

And with Zorock, unlike some mulch, there is no threat of insects, such as termites.

Zorock starts out as chunks of concrete and asphalt ripped up from roads, driveways and parking lots. It goes through an extensive process in an automated system – washing, shaping and coloring – before it is packed into 50-pound bags. The brothers invested about $1 million in automation to produce the stone, including designing their own coloring machine. Zorock prices range from $5.50 to $9 per bag, depending on the distributor.

Recycled aggregate has but a few uses. Primarily, it’s used as a base for concrete and asphalt paving and the installation of paving stones and other bricks. Some larger paving companies grind up old driveways on the job site and redistribute it as base. It’s an extremely efficient way to pave. But only larger companies have such grinding machines; smaller companies must dump old concrete and asphalt. And if it’s not reused for base, often it heads for landfills.

So, Billy Zorn asks, what could be better than turning it into a landscape stone? Here’s a recycled product with environmentally friendly – let’s call it green – features.

Spreading Zorock, which comes in six colors, can be a do-it-yourself project or can be done professionally by landscape contractors. Either way, it’s relatively easy to get, easy to install. A porous landscape fabric is rolled out to cover the planting bed, walkway or design area, and the rock is spread on top, usually to a depth of 2 inches. There is some maintenance; a sealer should be applied twice each year (from a pump sprayer) to maintain the product’s color.

Michael Zorn says the cost of the sealer – $20 a gallon, which covers 200 square feet – is comparable to replacing colored mulch every spring or so.

So far, Zorock has been a commercial hit. Michael Zorn has been making forms for clients, so company emblems can be displayed as “lawn plaques.”

“The next step is getting it in the hands of homeowners,” Billy Zorn says.