Topdressing is the practice of placing soil, similar in make up to the existing soil, over the top of turf to promote growth, improve drainage or level low spots. Sanding is primarily used to level low spots in bermuda turf. However, an excessively deep layer of sand or soil can cause the turf to die in that spot especially where Zoysia is concerned. Sand and soil layers should never be applied thicker than 1″ for bermuda and 1/2″ for Zoysia. If additional leveling is required then topdressing with a soil/sand mixture should be the method used as excessive applications of pure sand will result in areas of turf which dry out faster than the surrounding turf (we call these hot spots). These areas can become severely compacted. You will also need to water more frequently to maintain sufficient soil moisture for the roots and aerate at least twice per year.
Home lawns are not designed to be maintained like golf course greens and therein lies the problem. Because golf greens are constructed with a very specific soil mixture they can be maintained at short mowing heights. Compaction is also a problem on the course but the greens are aerated multiple times each and every year to reduce the problem.
When sod is installed at the house the sub soil is not properly constructed. Just adding “top soil ” to the yard before sodding is not the same thing as completely constructing a specialized subsoil structure just for the turf.
If the lawn is then top dressed with sand, compaction levels increase even more. Subsequent short mowing with a reel mower, in some cases, can further increase compaction. Root depth becomes shallow because the soil is too compacted for deep root growth and the turf cannot produce adequate food because the leaf blades are so short. Subsequently the turf is not healthy and is more susceptible to winter kill, heat injury and attack by fungal disease pathogens.« Back to Glossary Index