Turf - Heat Dormancy

Hot, dry conditions are with us across the state leading to heat dormancy in turf. Some information on this phenomena.

Cool season turf species - fescues, bluegrasses, and ryegrasses - all will be going into heat dormancy in areas that are not irrigated at this time. Hot, dry weather triggers this dormancy. This is a natural survival mechanism for these plants and once cooler, more moist conditions occur, they will green back up.

While these plants survive by going dormant, it is critical to avoid traffic and other stresses during these periods. Reduce mowings and avoid heavy usage to reduce the risk of long term damage and stand loss. Summer weeds such as crabgrass can grow rapidly in head dormant cool season grasses and must be controlled.

Irrigation can counteract heat dormancy and keep the grass green and growing. In lower maintenance areas, you should consider eliminating irrigation and allow the heat dormancy to occur. This will reduce maintenance costs considerably and does not harm the grass at all.

Gordon Johnson, Extension Horticulture Agent, UD, Kent County