A properly programmed sprinkler system controller ensures plants receive the correct amount of water while promoting water conservation. Over-watering wastes resources and is detrimental to plant health, often leading to shallow root growth and increased disease susceptibility. Accurately setting your controller translates directly into a healthier landscape and more efficient water use. This guide walks through the components and programming steps for a standard residential irrigation timer.
Understanding Your Sprinkler Controller
The controller serves as the system’s brain, governing when and for how long water is delivered. The interface typically features a main dial or selector switch that moves between different setting modes.
Common dial positions include:
- Off (to stop all automatic watering)
- Run or Auto (to execute the programmed schedule)
- Set Clock/Date
- Set Start Times
- Set Run Times
- Set Water Days
The flow of water is organized around three primary terms: Zone (or Station), Program, and Time settings. A Zone corresponds to a specific area of the landscape, connected to a single valve and a group of sprinkler heads. Run Time (or Duration) is the amount of time a single zone will water during a cycle, often ranging from three to forty minutes depending on the sprinkler head type and plant material.
A Program is a collection of zones set to run sequentially based on a shared schedule, identified by letters like A, B, or C. This allows separate schedules for areas with different watering needs, such as turf grass (Program A) and drip-irrigated shrubs (Program B). The Start Time determines when a selected program begins; only one start time is needed per program, as the controller runs all assigned zones one after the other.
Step-by-Step Guide to Basic Programming
The initial step in setting a schedule is establishing the controller’s internal timeline. Move the selector dial to the Set Clock or Set Date/Time position to input the current time and day. Confirm the correct AM or PM setting to ensure the system waters during the intended early morning hours.
Next, select a Program, typically Program A, using the dial or a dedicated button. Move the dial to the Start Times position and input the desired time for the watering cycle to begin. Watering is ideally set between 3:00 a.m. and 6:00 a.m. to minimize evaporation and reduce the risk of fungal diseases.
After setting the start time, switch the dial to the Run Time or Station Duration position. Systematically cycle through each zone number, entering the specific number of minutes each zone should run. For example, a zone with spray heads might require 8 minutes, while one with rotors may need 25 minutes. If a zone is not intended to run under the current program, its duration should be set to zero.
The final step is defining the Water Days or Schedule. Move the dial to the corresponding setting to choose specific days of the week, or select an interval cycle, such as watering every third day. For turf, it is recommended to water infrequently but deeply, perhaps two or three days a week, to encourage deep root growth. Once all parameters are set, return the dial to the Run or Auto position to activate the new automatic schedule.
Optimizing Water Use with Advanced Features
Several features allow for easy modification of the foundational schedule to match changing weather conditions, significantly improving water efficiency.
Seasonal Adjust (Water Budget)
The Seasonal Adjust or Water Budget feature increases or decreases all zone run times within a program by a single percentage. During the hottest months, this percentage is typically set to 100%, representing the maximum required duration. As the weather cools, the percentage can be manually lowered (e.g., to 70% or 50%) to reduce the duration of all zones simultaneously. This eliminates the need to manually adjust the run time for every zone. Some advanced controllers automatically adjust this percentage daily based on local weather data.
Rain Delay and Cycle/Soak
The Rain Delay function temporarily suspends the watering schedule for a set number of days, usually between one and fourteen. This allows the user to pause the system after significant rainfall without losing the original programmed schedule. Once the delay expires, the controller automatically resumes the normal schedule. Furthermore, some controllers offer a Cycle and Soak feature, which breaks a long run time into several shorter cycles with a short pause. This technique allows water to soak into dense or sloped soil, preventing wasteful runoff and promoting better absorption.
Testing and Manual Operation
The ability to manually operate the system is useful for maintenance checks or delivering supplemental water outside the regular schedule.
Manual Single Station
Most controllers allow for a Manual Single Station run, where the user selects a specific zone and sets a temporary run time. This is helpful for inspecting individual sprinkler heads for clogs or breaks.
Manual Program Run
The Manual All Stations or Manual Program function initiates a complete run of all zones within a selected program. This is often used at the beginning of the season to test the entire system sequentially. The controller runs each zone for its currently programmed duration or for a duration specified during the manual activation.
To initiate a manual test, turn the dial to the Manual position, select the desired zone or program, and input the run time. The system begins watering immediately and returns to its automatic schedule once the manual cycle is complete. After any manual operation, ensure the dial is returned to the Auto or Run position so the programmed schedule resumes on its next designated day.