Landscaping is good thing because it eliminates hardscapes and, in so doing, reduces the strain on the sewer system from storm water runoff and reduces the heat island effect. Irrigation systems to keep your landscaping alive and healthy, however, can result in tremendous water waste if not designed and used properly. If you have a brownstone back garden, deck or rooftop garden, chances are you have a double-digit increase in your water consumption in the watering months. Some experts estimate that more than 50 percent of landscape water use goes to waste due to evaporation or runoff from the irrigation system running when the ground is already wet. Refer to our article Navigating Green Building Guidelines Part I: LEED® for Homes Guidelines  to use the LEED for Homes as a guide to how to design an efficient irrigation system. There are simple things you can to reduce your use of potable water in the garden.

• Drip irrigation systems use between 20 to 50 percent less water than conventional in-ground sprinkler systems. They are also much more efficient than conventional sprinklers because no water is lost to wind, runoff, and evaporation.

• Harvest rainwater – It’s relatively easy and inexpensive to attach a rain barrel to the end of a gutter downspout. You can even hook it up to a drip irrigation system. Check out the Rain Barrel Guide  for information on choosing and using a rain barrel.

• If you have extensive landscaping in your garden that uses irrigation, get a controller with a moisture sensor or weather-based technology. These state-of-the-art irrigation controllers, called Smart, ET or Evapotransporation controllers, can conserve water by not watering when it has, or will, rain and can zone your landscaping so that you can selectively program it to water less those areas that contain plants that need less water. On the whole, however, plant drought-resistant plants. See the New York City Park’s Dept. website for a guide to drought-resistant plants for NYC. Do not use misting systems because a substantial amount of water in the mist is lost to evaporation. Generally, water in the early morning or late afternoon when the water won’t be subject to quick evaporation from the sun.

Check back for our upcoming article on green roofs.