Cary studies how to get greener lawns with less water

Cary has teamed with North Carolina State University to test new irrigation control devices on residential lawns. The test will last 18 months.

“We always struggle with how to set the sprinkler. Is it too much or too little? And there (were) some new technologies, and we wanted to give it a try,” said Mark Polizzi.

Garry Grabow, an assistant professor at N.C. State, dug up the family’s yard and installed a soil moisture sensor four inches deep in the ground.

“(The sensors) are kind of new to the southeast, especially to North Carolina,” Grabow said.

The sensors transmit to a monitor that attaches to the sprinkler control system, which will prohibit or turn off irrigation if it’s too wet.

“It’s sort of like having a rain switch in your soil,” Grabow said.

Six of the study’s participants will get the moisture sensor. Six others will use a sensor device that attaches to their houses. Six others will receive education on irrigation management. The final six participants will be the control group and do what they always do.

“We’re very interested in how these technologies are going to be effective here in our soils, out weather conditions (and) in our residential settings,” said Marie Cefalo, Cary’s water conservation coordinator. “The results will help guide the direction of our water conservation program.”

If one of the devices delivers a greener lawn with less irrigation, the Town of Cary could encourage homeowners to use them, with incentives, or require their use. The town could also invest more in outreach efforts, if the education group shows better results.

“If there’s a way we can be more efficient, then it’s worth it,” said Kelly Polizzi.

Cary officials said they spent about $3,000 for the equipment to do the tests. Homeowners with the devices will be able to keep them after the 18-month study.