A reader of Susan Harris’ recent post about the display of Synlawn synthetic grass at the National Building Museum in Washington, D.C. asked about the relative environmental merits of synthetic versus real grass.

The short answer, I think, is that while lawn, especially as presently cultivated, is a poor environmental solution, this synthetic grass is far worse.

When I went to the SynLawn website, I found its fine print revealing.  For instance, while the headlines trumpeted the synthetic grass as plant based, a careful reading of the articles included reveals that that is only partially true.  Apparently, materials derived from sugarcane and soy beans are used to replace “up to 60 percent of petroleum-based polymers.”  Clearly, a lot of petroleum products are, in fact, used in the manufacturing of this landscape treatment.

However, it is true, apparently, that plant products are also used.  The first notable point about these materials, in my opinion, is that they are not plant wastes or agricultural byproducts.  They are foods.  In a world where many people go hungry, what are the ethics of using foods to create faux grass?  I’ll let the reader decide that.  Rather, I’ll point out that neither sugarcane nor soybeans come without an environmental price tag.

Cultivation of sugarcane requires large inputs of nitrates, which are manufactured from natural gas, a fossil fuel.  Sugarcane also has a big appetite for phosphates, and the runoff from the canefields promotes water pollution and algal blooms wherever sugarcane is grown.  Soybeans have their own special costs.  The on-going boom in global soybean production is second only to cattle ranching in driving destruction of savannahs and tropical forests.

No environmental services

What do we get in return for these costs?  Not much, aside from a vista of “clean and green.”  Live turf, if properly cultivated, will help somewhat to filter the water that falls on it, can sequester substantial amounts of carbon in the soil, and helps cool its environs in the summertime.  Synthetic turf offers none of these services.

Installing faux grass does end the need for mowing and the air pollution that creates, but Synlawn won’t renew itself like a living vegetation does.  A quick web-check turned up estimates of the lifespan for artificial turf ranging from 10 to 15 years, at most 20 to 25; the Arizona distributor for Synlawn offers a 15-year warranty.  At the end of that time, the synthetic grass will have to be removed and replaced.  The resulting waste is theoretically compostable (according to Synlawn), but my bet is that it will go to the landfill.

Real turf sequesters significant amounts of carbon in the soil to help combat the greenhouse effect

If you are concerned about wildlife, you know that even a weedy lawn provides relatively little support for pollinators.  A synthetic lawn, however, provides none.

If you are really tired of mowing and want a more environmentally beneficial groundcover, I suggest you consider planting a meadow.  That’s what I’m going to do in my back yard this fall.