"Lasagna-style" composting

By Denise Ruttan

Photo by Tamara Hill-Tanquist

Leaves are one material that can be used in the "brown layer" of a lasagna garden.

Unlike its name suggests, "lasagna gardening" is not about pasta.

Also known as sheet mulching, it's a no-till, no-dig gardening method that turns materials like kitchen waste, straw and newspapers into rich, healthy compost.

"It uses up stuff that you would normally put out at the curb to say goodbye to and makes it valuable to grow on," said Larry Steele, a master gardener with the Oregon State University Extension Service, adding, "It's for the lazy gardener. You don't have to move compost. It's already there."

Steele uses lasagna gardening at his home in Millersburg and also built some lasagna-style beds in the master gardener demonstration garden in Albany.

The vegetable garden at the historical Brunk House in west Salem also features examples of this technique. Lee Ann Marsaglia, formerly an Extension-trained master gardener in Polk County, established the beds years ago. Today, Marsha Graciosa of Salem is one of the master gardeners who tends to them.

"It's really the only way to go," Graciosa said. "Once you start using it for a couple of years you won't do it any other way."

You can start making your lasagna any time of year.

"We usually layer it up in the fall as we are putting the beds to bed," Graciosa said. "We cover it up with plastic. When it comes time to take off the plastic, we have great new compost and plant on that."

To get started, Steele advises spreading 1 to 2 inches of a mix of high-nitrogen "green" material on the ground such as vegetable peelings, grass clippings, fresh manure, coffee grounds or plant cuttings without seeds. Then top that with 1 to 2 inches of a mix of high-carbon "brown" material such as leaves, straw, black-and-white newspaper, cardboard, sawdust, tea bags or wood ash.

Alternate the green and brown material. The pile could grow 2 to 3 feet high but continually shrinks as it turns into compost. It doesn't matter if green or brown material makes up the last layer, Steele said. Unlike hot compost, you don't need to turn the pile. You can cover the pile to protect it from rain with more mulch or black plastic, but do not cover it too tightly.   

A word of warning: this method of composting is slow. It takes anywhere from several months to a year for finished compost to form. The compost can form through the growing season.

For a visual explanation of how to do lasagna gardening, check out the following comic book created by some of Extension's master gardeners in Polk County: http://bit.ly/WfyAWf. />

If you want to see an example firsthand, stop by the gardens at the Brunk House on Highway 22 near the junction with Highway 51 in west Salem. The demonstration garden in Albany is at the Linn County Fair and Expo Center and features lasagna-style gardening, although the beds are older and planted with perennial flowers. Both garden sites are open to the public.