The Secret to Good Lawns, Good Soil

Dr. Kevin W. Frank
Assoc. Professor & Extension Turf Specialist

I recently rode along with a landscape services provider to visit what he called some difficult properties.  On these visits I usually only bring a couple items, camera and soil probe.  The first home lawn we visited was indeed difficult.  Upon arriving at the site first impressions were a lawn that was thinned, stressed, and not surviving the recent heat spell very well.  Walking the lawn it quickly became evident that soil moisture was not the problem, well actually it was the problem, too much water.  To this point it’s been a very wet summer and any irrigation a homeowner might be adding when it’s not needed can easily push a lawn from adequately watered to soaking wet.  As I started to probe the soil in various parts of the lawn it became obvious the underlying soil was not helping the lawn.  In most areas no matter how hard I leaned on the probe I could only force it into the soil 2-3 inches.  This was the typical example of turf trying to grow on compacted clay.  Sometimes on visits there’s a moment of truth, on this visit it was looking at the neighbors picture perfect patch of green next to this struggling lawn. 

When I pushed the soil probe into the neighbors lawn the probe went down about 10 inches easily.  Bottom line, growing turf on compacted, high clay content soils is a challenge.  As the story was slowly revealed, the area of the lawn that was really struggling was heavily trafficked and compacted following a recent pool and deck installation.  Following construction, it was not clear if any efforts were made to break up the compacted soil before sodding, my soil probe would say no.  Best solution of course would be to start over, bring in 4-6 inches topsoil and sod or reseed the lawn.  For most homeowners this is an unrealistic solution based on cost and pain.  The less disruptive solution is to put the lawn on a regular core aerification and fertilization program and to monitor watering closely to avoid a saturated, waterlogged soil. 

The second visit I wouldn’t have found on my own.  My inclination when traveling to a neighborhood to visit a lawn is to look for the bad lawn and stop there.  On this visit we drove right by the bad lawn and stopped at a lawn that from curbside appeared to have few problems.  As we walked the lawn in silence I found some small areas with dollar spot and a couple areas with necrotic ring spot that appeared to have been successfully managed to avoid turf loss or the sunken ring.  Both of these I considered minor blemishes considering the hot stretch of weather we just went through.  Finally I basically raised my hands and said, what’s the deal here?  My host for the day replied with, they just don’t think it’s as good as the neighbors, not as uniformly green.  There were some patches of fine fescue in the lawn that some could find objectionable if they want a perfect Kentucky bluegrass lawn but it seems unnecessary to me to start this lawn over or kill off those patches.  We’ll write this one off to unrealistically high expectations.   

High quality home lawn with equally high homeowner expectations.