I have not seen any figures, but I bet the gardening/land management activity most often practiced by landowners is mowing. When the early English noblemen began the practice of running a few sheep in front of their mansions to keep the grass short, they started a custom that has become synonymous with being a homeowner—mowing the lawn.
With the spread of suburbia and the marketing departments of John Deere and Scotts and Toro, the practice has become almost mandatory. In fact, many municipalities require homeowners to keep their grass mowed. But do lawns really make sense? And is frequent, close mowing good for the grass? What about the use of water?
It is important in any discussion of lawns and mowing to make a distinction between two different types of grass. Lawn grasses are what are called turf grasses and naturally grow short. Most have stolons (runners) above ground and rhizomes below ground that cause the grass to spread out and cover an area. The non-native turf grasses most commonly used in this area are St. Augustine and Bermudagrass. Native grasses that grow similarly are buffalograss and common curly mesquite. Most other native grasses are referred to as bunch grasses and they grow taller and in clumps.
Lawns in general, but especially grasses like St. Augustine and Bermudagrass, use an inordinate amount of resources. First, St. Augustine requires many times more water than we usually get in a normal year, so lots of watering is required for it to survive. Bermudagrass requires less, but still requires frequent watering. These nonnative grasses also require frequent applications of fertilizer which uses lots of resources to manufacture, and lawn mowers are some of the most polluting gas engines around. Furthermore, monocultures of these grasses are poor habitat for anything except perhaps grackles. In short, these lawns are not very environmentally friendly.
One could minimize some of these problems by mowing less frequently and with the mower set as high as possible. Doing this allows the grass to shade the soil better and thus allows the soil temperature to be lower. This not only reduces water evaporation from the soil but keeps the soil microorganisms more healthy. One of the easiest things homeowners can do to reduce the impact of lawns is to mow less frequently. During droughts, I have seen folks running a lawnmower over short, dormant lawns where nothing was sticking up to mow and instead they were raising a huge cloud of dust. Just because it is Saturday and it is your usual mowing day doesn’t mean you should mow if the grass doesn’t really need it (actually the grass really never “needs it” for its own good, it is just our sense of aesthetics that seems to require it).
Not catching the cuttings but allowing them to be mulched and kept on the lawn, at least some of the time, returns nutrients back to the soil and thus reduces the need for fertilizer, plus it reduces the amount of waste going to our landfills.
Obviously the biggest saving of all of these resources would be to not have a lawn, or to have one of native buffalograss. Buffalograss requires far less water than the two non-native grasses discussed above, and it requires no fertilizer at all. Once established, it can live without water—going dormant in droughts and greening up after a rain. Buffalograss also usually needs mowing only once or twice a year. Reducing the size of lawns and replacing them with vines, other ground covers, or perennials all help mitigate some of the problems discussed above.
For those folks that don’t really have turf grasses, but keep the native grasses mowed short, it is important to understand that mowing bunch grasses frequently and too low will eventually weaken and kill the plant and it will be replaced by various weeds and grassburs that tolerate frequent mowing. The best times to mow native bunch grasses, if it is required, are in late June or July and again in December or January, and most do better if they are mowed to a height of four to six inches.
I can tell you from personal experience, that giving up the weekly suburban ritual and instead allowing native grasses to grow and mowing them only twice a year has sure freed up a lot of my time, and I don’t miss the mowing one bit.
Until next time… Jim Stanley is a Texas Master Naturalist and the author of the book “Hill Country Landowner’s Guide.” He can be reached at <jstmn@ktc.com>.