Turf - Topdressing Compost to Improve Turf Performance

Compost is an excellent amendment to improve turf performance. The following is a short article on the subject.

Surface applications of compost on established turf

Composts are frequently used as surface applications (topdressings) on established turf. This practice provides a means of gradually incorporating organic matter into the soil without causing extensive disruption of the surface. The two most limiting factors associated with this practice are finding suitable application equipment and working the material into the soil.

Since compost is light and bulky, a spreader with a large hopper is preferred. Modified manure spreaders with conveyor belts and brushes mounted on the back are ideal for spreading compost over large areas. Conventional tractor-mounted fertilizer spreaders have been used successfully, but may require many refills. If spreaders are not available, compost can be applied to the surface by spreading piles into a thin layer with a York rake or a grading blade. For applications over small areas, the compost can be spread with a shovel and worked into the turf with a leaf rake.

When applying compost as a topdressing, it is important to apply a thin layer (about ¼ inch) and work it into the soil. Successive applications of thick layers without soil incorporation will result in a build-up of organic matter at the soil surface that may cause rapid drying of turf roots and form a layer that restricts rooting into the soil. The best way to incorporate compost into the soil is through aeration. A good method of incorporation is to apply the compost first, followed by several passes with an aerator equipped with hollow-tines and a heavy drag mat attached. The drag mat will break-up the cores and mix the compost with the soil, dragging some of the mix back into the holes. This operation is best performed during cool/moist seasons when grass is actively growing. Aeration and dragging can be stressful to the turf during hot, dry weather.

Extracted from "Using Composts to Improve Turf Performance" by Peter Landschoot, Associate Professor of Turfgrass Science, Penn State University.