The answer to 'when to sprinkler system' is that the best time to install or activate your sprinkler system is in the spring, typically between April and May. This ensures your system is ready to provide consistent, efficient watering for your lawn and landscaping throughout the growing season.
Sprinkler systems should be turned on and tested in the spring after the last frost has passed in your area. This allows you to identify and fix any issues with the system before you need to rely on it for regular watering. It's also important to have your system winterized in the fall to prevent freeze damage to the pipes and components.