Landscape and Turf - Choosing a Compost

I just finished a class where we went over soil amendments and fertilizers. One of the best ways to improve a turfgrass or landscape area is with additions of compost. The following is a table from Penn State University on general guidelines in choosing a compost.

Appearance, size, and odor

Color: Brown to black
Size (surface applications): ¼ to 3/8 inch
Size (incorporated): ¼ to ½
Odor: “Earthy”

Physical appearance

Moisture content: 30 to 50 percent
Organic matter: Greater than 30 percent
Ash content: Less than 70 percent

Chemical properties

Carbon : nitrogen ratio: Below or equal to 30:1
Nitrogen: 0.5 to 3.0 percent
Phosphorus: Greater than 0.2 percent
pH: 6.0 to 8.0
Metals: Determined by state and federal agencies
Soluble salts: Depends on species, type of salt, concentration, and application method. Consult test lab or other expert to determine how this will affect the turf or landscape plants.

Use this information only as a general guide. Some composts have properties that do not fall within these guidelines yet are acceptable in certain situations. Others, though they may fit these criteria, may have serious drawbacks.

Reprinted from Using Composts to Improve Turf Performance by Peter Landschoot, Associate Professor of Turfgrass Science, Department of Crop and Soil Sciences, and Cooperative Extension. For the full article go to http://turfgrassmanagement.psu.edu/composts.cfm.