Good time to prospect for black gold

One of the easiest ways to get your garden ready for the potentially dry summer is to start adding compost to your beds now.

Compost is black gold to a garden. As a soil amendment, it is a rich source of the nitrogen, phosphorous and potassium that plants thrive on. It makes even the driest sand or gummiest clay beautifully crumbly, friable soil that’s able to hold water better. As a 2-to-3-inch surface layer of mulch, it also helps slow evaporation from the soil and blocks weeds from seeing the light of day and sprouting.

You can buy compost or make your own. Compost can be purchased in bags or in bulk from a number of local sources. Most nurseries and garden centers will have bags containing up to 3 cubic feet of compost. This is fine if you only need a small amount but can get expensive if you have a large area. Be prepared to pay a fair price, and please do remember you get what you pay for.

For large amounts, consider ordering it by the cubic yard from landscape supply companies. According to Lawrence McKinley, owner of Moore Landscape Materials and Fuel in north Spokane, most bulk compost is a blend of several different types of organic material and soil. Moore’s mix contains rotted bark and sawdust, sandy loam and black dirt. Other blends can also contain manures and animal bone and blood meal; all good sources of soil nutrients. Good composts like Moore’s are independently tested to ensure uniformity of the mix.

The cost of a cubic yard of compost in the Spokane area ranges between $17.50 and $30.00 depending on the company. The material can often be delivered, though some quantity and delivery restrictions can apply. Or you can pick it up in smaller quantities at the various vendors.

How much is a cubic yard? It’s about as much as will fit in the bed of a standard pickup truck.

Before you order, measure the length and width of the area you want to cover and plan on putting down at least 3 inches of material. A cubic yard spread 3 inches deep will cover about 108 square feet of ground.

Making your own compost starts with “green” and “brown” plant material, a little water and a space to set up your pile. Green plant material comes from fresh green garden trimmings, lawn clippings, weeds (without seeds) and kitchen vegetable trimmings. Brown material is basically dried and dead plant material from leaves, spent plant material from the vegetable garden and dried weeds and grass clippings. Even a limited amount of pine needles can be used in the mix. Do not use grass clippings treated with herbicides as the residue can affect the plants the compost is ultimately put on.

A compost bin can be made of any material that will hold up a 3-feet-by-3-feet square pile and is porous to let air through. It can be made out of something as simple as wood pallets, found for free near industrial areas, or as sturdy as wire mesh or as complicated as barrels mounted on a frame that can be rotated periodically or a commercially designed product designed to look “pretty” (and usually expensive).

Coarsely chop all the material, other than grass clippings, using a shredder or a lawn mower. Mix the materials in a ratio of two parts green to one part brown. This can mean two pitchforks, buckets or wheelbarrows of green to one of brown. As you mix, water the pile so that the mix is as wet as a wrung out sponge.

Mixing the green and brown material together gives the microbes the best possible source of food to work on. And they work fast. Within a few hours, you should be able to feel some heat if you put your hand into the pile. Within two days, the temperature inside the pile should reach 140-160 degrees, enough to make the pile steam on a cool day and cook most weed seed and bugs. This happens because the bacteria start eating the material and generate heat in the process. As the temperature rises, different bacteria join the process. Once they have eaten all the available food, the pile will begin to cool down, usually after five days or so.

When the pile temperature drops to about 100 degrees or the pile feels lukewarm, it’s time to turn it. Fold the outside layers of the pile into the center of the new pile. Moisten the pile as you turn it. If you do everything right, you can have a finished batch of compost in about a month to six weeks. That means that by the time the hottest summer weather hits in mid-July, you could already have made two batches of compost.