It's nearly spring and time to confront a common gardening problem: How can one create healthy soil while keeping the weeds at bay?

By sheet mulching -- putting down layers of organic material that stimulates the microbial community and improves the biological and physical texture, according to Jason McKenney, agricultural manager at Hidden Villa in Los Altos Hills.

Simply said, if you are looking for an easy way to add nutrients to your soil, improve soil structure and suppress weeds, sheet mulching is an effective, chemical-free and no-dig gardening technique in order to help accomplish this goal.

The basic concept is to place layers of nitrogen- and carbon-rich materials on top of the soil, allowing them to break down naturally over time.

McKenney, who's been managing the farm since 2008, will be teaching a class as part of Hidden Villa's "Home Farm" series on Feb. 16.

He works with three full-time interns and plenty of volunteers to farm the 9 acres of prime, arable land. One of his duties and responsibilities is teaching different types of gardening classes to the local community.

Noting that healthy plants need a strong, very diverse and high volume microbiological community, McKenney is a big supporter of sheet mulching.

"What we are trying to do is find the ways that good soils are made in nature and mirror this natural process," he said.

Class participants will go over the process of sheet mulching, learning the biology of it step by step. After the theoretical part, attendees will then get hands-on experience by doing some sheet mulching of a few areas at the farm.

McKenney explains that shovels, rakes, worm compost, pile compost, cardboard boxes and lots of wood chips or leaf mulch are all that is needed.

Compost materials, including worm castings, will be made available to class participants. "If they want to take a bag of our compost to use in their garden, they are welcome to," he added.

One key use for sheet mulching is transforming a lawn into an adequate garden bed within several months. It is an easy, sustainable farming practice that lets nature do the work to replenish nutrient-poor soil, he explained.

Hidden Villa is offering this class in winter because it is an excellent time to put down a layer of sheet mulch and to allow it to decompose in the rain.

"With rain or irrigation you'll have a steady decomposition of those materials, and an enrichment and even enhancement of the microbiological community," McKenney said. "After three months of sheet mulching in an area where there was lawn, you will have friable useful soil underneath the mulch."

Then the garden should be ready for planting by about mid-May.

The great advantage of this technique is its user-friendliness. It is great for any gardens or plants and soil, especially vegetable gardens, he said.

A graduate of Brown University with a major in biology and environmental studies, McKenney, 43, worked as a biology teacher on an organic farm, later establishing his own farm in Half Moon Bay.

Just as McKenney was forfeiting his land lease there, former Hidden Villa farm manager Andy Scott was transitioning to retirement. Perfect timing for McKenney to make a fresh start.

Now, the music lover spends up to 60 hours a week during the high season -- which is fall -- working on the educational farm.

When McKenney has a free minute, he enjoys cooking with his fiancée who also works at Hidden Villa, as well as building and remodeling.

Editorial Intern Marion Hohlfeld can be emailed at mhohlfeld@paweekly.com.

What: Home Farm Workshop: The Winter Garden

When: Sunday, Feb. 16, 1 to 3 p.m.

Where: Hidden Villa, 26870 Moody Road, Los Altos Hills

Cost: $40

Info: Hidden Villa or 650-949-8650