Under Drought Conditions, an Occasional Flush Maybe Warranted
One of the oldest rules for irrigating turf, primarily lawns during the summer is “one inch of water a week”. The concept behind this rule of water heavy infrequent is to provide water to the soil that is lost through evapotranspiration and to keep the turf in a more “hardened off” state that helps provide protection from heat and moisture stress.
Although overwatering is a major problem on most golf courses, severely reducing the amount of water over time on a sand rootzone during an extended drought period can be detrimental. On putting greens and other highly maintained turf, watering tends to be light and frequent or as infrequent as possible to maintain as firm a playing surface as possible. Over an extended period where rainfall is absent or drought conditions persist, materials like salts, minerals, dust, etc. can start to accumulate in sand rootzones. An occasional flushing or an “inch of water a week” idea may help remove salts and minerals that accumulate in the rootzone.