You don't need good soil or backbreaking labor to produce a bounty of vegetables this growing season. All you need is some old straw.

That's the gospel one local landscaper is preaching to community-education classes throughout Minnesota and Wisconsin this spring.

It's called straw-bale gardening, and it's basically a variation on container gardening, according to Joel Karsten, the Roseville horticulturist conducting the classes. The bale acts as the container and the decomposing straw within the bale serves as the "soil."

"The plants draw all their nutrition from the straw bale," Karsten said.

Straw-bale gardening has many benefits, according to Karsten: The bales retain moisture, reducing the need for watering. "There's more airflow, less disease and no weed seeds like in typical topsoil," he said. It's an ideal method for gardeners with physical limitations, because there's less bending and heavy lifting than with traditional gardening. And at the end of the growing season, the straw-bale garden can be composted.

It's also a solution for those whose soil isn't rich enough to nourish plants. "Often in new developments, if you lift the sod, you'll find rocky construction dirt that's deficient for growing a garden," he said.

Although straw-bale gardening isn't widely practiced in the Twin Cities, it's nothing new. "My dad was a nurseryman, and he used to put potatoes in straw bales," Karsten said.

And Karsten isn't the method's only promoter.

"It's a very viable way to grow plants," said Rick Abrahamson, a former University of Minnesota Extension agent who posted an article about straw-bale gardening on the Clay County Extension website several years ago. Abrahamson did add one piece of advice: "It works better on old straw than new. It's best to find straw from the year before, that's starting to rot."

Karsten's classes focus on straw-bale vegetable gardening, but those who want to beautify their bales can plant plugs of flowering annuals in the sides of the bales, he said.

For more information and a list of classes, visit www.strawbalegardens.com.