Once the temperature begins to warm up and there is no longer a chance of freezing temperatures, you can start up you sprinkler system. De-winterizing your irrigation system in spring is not that difficult. You will need at least a flat head screw driver and some pliers.
You should use infrequent, deep watering cycles when programming your irrigation controller. This promotes better root development and lowers the chance of developing root rot. Allowing your yard a chance to dry out between watering periods also makes weeds less likely to propagate. Following this advice will get you greener and healthier grass that will perform better in the heat of summer.