The answer to 'how to maintain irrigation system' is to regularly inspect, clean, and test your irrigation system to ensure it is functioning properly. This includes checking for leaks, cleaning filters and sprinkler heads, and adjusting the system's programming to match the changing watering needs of your landscape.
It's recommended to perform a full system inspection at least once a year, typically in the spring before heavy use. You should also visually check the system periodically throughout the growing season and make any necessary adjustments or repairs. If you encounter any major issues or need to make significant changes to the system, it's best to consult a professional irrigation technician.