FIMBY: Make your own compost; save money and water

This is the latest installment of our Food in My Back Yard series on edible gardening.

Healthy soil makes for healthy plants. The right environment for roots not only produces more and bigger tomatoes, it saves water (and money), too.

But how do you turn bricklike clay into a plant-friendly paradise? Start with banana peels, coffee grounds, dried leaves and other “green waste.” The result is garden gold.

With a wealth of organic material, healthy soil retains moisture while creating a happy home for microorganisms, which convert those decaying leaves into nutrients that roots can absorb. Adding compost to soil and topping with mulch mimic nature’s way of recycling leaves and other plant products to feed all those hard workers underground – and benefit the plants, too.

Placer County master gardeners Mariellyn Schoenhoff and Richard Huntley recently presented a mulch and composting workshop hosted by the San Juan Water District in Granite Bay. They showed participants how to turn kitchen scraps and yard debris into rich compost and mulch.

People also can see composting in action at local master gardener demonstration gardens such as the new Loomis Demonstration Garden at the Loomis Library, Sacramento County’s Fair Oaks Horticulture Center, and the Sherwood Demonstration Garden in Placerville.

“Before I became a master gardener, I had no idea what was going on (in the soil),” says Schoenhoff, who lives and gardens in Auburn. “I didn’t really think about it.”

Now, she sees the benefits of compost and mulch daily in her own garden. “Both definitely help soil health a lot,” she says. “Adding compost helps open air pockets and lets roots have more air and water access. The soil is not so compacted. As the compost and mulch break down, it supports microorganisms. It maintains moisture so you use less water.”

For her home landscape, Schoenhoff uses a three-bin composting method. Fresh kitchen scraps and green waste go into the first bin. As it ages and breaks down, that material is transferred to the second bin where it further “cooks” and decomposes. When ready, the compost is moved to the third bin, where it awaits use in the garden.

This method takes time; it’s usually three to four months from kitchen waste to garden-ready compost. “Hot method” compost – with temperatures over 140 degrees F. – breaks down in about half the time, but kills worms, Schoenhoff notes. (It also can catch on fire.)

Composting is like cooking; it requires a mixture of certain ingredients, monitoring and occasional stirring for success.  And as with home cooking, you know everything that goes into that compost -- no awful surprises such as herbicides or plant pathogens.

In the first bin, put layers of “greens” and “browns,” Schoenhoff instructs. “Greens” aren’t necessarily green in color; the same goes for “browns.” Instead, it refers to freshness and moisture level. “Green” is moist and fresh (like newly cut grass); “brown” is dry (like fall leaves).

“For my ‘greens,’ I use a lot of vegetables and kitchen trimmings, grass clippings, eggshells, citrus, banana peels,” she explains. Also add other kitchen waste such as coffee grounds or tea bags. “I have a compost bucket on my kitchen counter. I cut things into 1-inch pieces so they’ll break down faster.”

Never use dairy products or oils, meat, chicken, fish or bones; those ingredients will attract pests and need higher heat to break down safely.

For “browns,” Schoenhoff adds “a fair amount of dried leaves, woody trimmings from my shrubs, shredded paper, cut-up cardboard, rice straw and shavings from my chicken coop.”

To speed the process, she cuts all those ingredients into small pieces, less than an inch square. She uses no wood bigger than a pencil width.

“Compost needs water and air,” she adds. “You want to keep the compost pile moist like a wrung-out sponge. (She adds water with a hose as needed.) Then you turn it with a pitchfork to aerate regularly (every few days).”

When finished, the compost can be dug into the soil or spread around plants as a nutrient-rich mulch.

Mulch is like a blanket that maintains soil moisture while also keeping plant roots comfortable during summer heat. It’s vital around trees and shrubs.

“You don’t have to water as much,” Schoenhoff says. “It also suppresses weeds – which cuts down on work – and maintains soil temperatures, helps prevent erosion and improves soil structure.”

Schoenhoff’s favorite mulch: Wood chips.

“Native wood chips are considered the best because they are native,” she explains, noting native incense cedars, pines and oaks – including chipped into mulch – support native wildlife. “I approached a local company trimming trees in my neighborhood and told them, ‘I’ll take your wood chips!’ And they gave me a great big pile.”

For mulch to be most effective, Schoenhoff suggests layering it with compost underneath. “Water the soil, apply a 1-inch layer of compost, top with 2 inches of mulch, then water again. That way, it will retain soil moisture a lot longer and you’ll be ready for summer.”