Depending your climate and location, it may be time to start thinking about blowing out your system! Winterizing is important because it keeps your Irrigreen system and pipes free from freeze damage. Refer to this map from the Weather Channel to determine when to winterize:
It's important to pay attention to the weather and do this process at least a week before the freeze.
Sprinkler system blowout, for winterizing, consists of forcing compressed air through the system, which pushes the water out of the pipes, through the digital sprinkler heads (and mechanical heads, if any).
Follow appropriate safety procedures when working with compressed air.
Air compressor with 20 gallon tank (large systems may require a larger tank)
Air hose
A coupler or adaptor that fits your backflow blowout port
A pair of safety glasses (wear when working with any power equipment, including air compressors)