The Climate-Friendly Gardener

The Climate-Friendly Gardener
A Guide to Combating Global Warming from the Ground Up





[Excerpt] Scientists have yet to reach a consensus on the impact lawns have on global warming, but here are some tips for making yours as climate-friendly as possible:

Minimize watering. Added water appears to play an important role in increasing nitrous oxide emissions from lawns,57 and in some locales, considerable energy is required to pump water from its source to homes, resulting in CO2 emissions. There is also the fact that outdoor water use, which represents 50 to 75 percent of total residential use in most of the United States, puts pressure on available resources.58 If you must water, do it during the coolest part of the day to minimize losses from evaporation.
Fertilize carefully and leave grass clippings on the lawn. Grass clippings can increase carbon storage in the soil by as much as 59 percent,59 while also substantially decreasing your need for fertilizer. Mulching mowers create fine clippings automatically.

Mow high for healthy, less-thirsty roots. Taller grass shoots mean deeper, healthier roots that require less watering, so set your mower blade to three inches or higher, and never remove more than one-third of the grass blade at a time.60 Mowing regularly (with an electric or push mower if possible) promotes continuous root growth and shedding, which deposits more carbon into the soil. Also, keep your mower’s blade sharp to minimize damage to grass plants and reduce water loss and stress.

Choose the right grass. If you’re thinking about putting in a new lawn, consider whether native ground covers—which usually require less water and maintenance than grass but don’t tolerate heavy foot traffic—could serve your needs. If you decide to go with turf grass, choose varieties that will flourish in the conditions presented by your yard, with a minimum of inputs. For example, southern zoysia grass and native mid western buffalo grass hold up to summer droughts with minimal watering.61 Kentucky bluegrass, while popular in many areas, tends to fare poorly in shade and when faced with drought or pests, and demands more fertilizer than other species.

For advice about low-maintenance grasses or ground covers suited to your yard’s specific conditions, consult your state’s Cooperative Extension office (contact information is listed at http://www.csrees.usda.gov/Extension).

Source: The Union of Concerned Scientists