What do I do if my lawn is drought stressed?

Moisture is an essential element in maintaining a vigorous, healthy lawn.  Given that most grasses are made up of 70% to 75% water, losing more water than a plant is taking in can cause over-stressed lawns.

Several factors can make a New Jersey lawn more susceptible to drying out, other than general lack of moisture.  Grasses such as centipedegrass, bentgrass, and annual bluegrass are more prone to drought stress than grasses such as tall fescue and bermudagrass, which both have a higher tolerance for low moisture conditions.  In addition, the type of soil is key to maintaining a healthy lawn.  Clay and sandy soil both impede turfgrass’ ability to hold moisture.  Lawns in New Jersey with high thatch content, as well as lawns mowed shorter than recommended for the particular grass type can both make a lawn more prone to drought stress. 

Symptoms of drought stressed lawns can be seen by most homeowners soon after the lawn is under stress.  The first and most obvious symptom is that the turfgrass will change in color from bright green to a gray or blue-green color.  Also, grass will not spring back as quickly from footprints or lawn mower wheels.  When the grass becomes tan, this indicates that the grass has gone into dormancy and steps must be taken immediately to prevent permanent damage.

Since drought stressed turfgrass can be easily damaged, lawns with such symptoms should not be mowed.  Not only is this type of grass not growing, but its lack of moisture leaves it less able to protect itself from collapse and permanent damage.  Weeds will still typically grow during drought periods, resulting in an uneven appearance of a lawn and a homeowner’s desire to cut the lawn.  However, mowing should not take place in these conditions, because even mowing at a higher height can still result in lawn damage.  The weight of the mower will most certainly leave stripes of broken grass where the wheels have been.

To manage drought stressed lawns, action generally needs to be taken immediately, once lawns begin to wilt and discolor.  Sufficient watering is necessary, but when not possible, lawns should be watered with at least a half inch of water every week.   This will at least keep the plant alive, even if it remains in dormancy.  Do not mow the lawn when it is obviously drought stressed.