Smart Controllers and Rain Sensors: Which Ones Are Worth It

Florida requires a functioning rain sensor or equivalent shutoff on automatic irrigation systems, and a great many of them stopped working years ago without anybody noticing.

Test yours

Trigger the sensor manually — most types can be activated by hand — and start a zone. If it runs, the sensor is not doing its job. That is a five-minute check and it is worth doing annually.

Sensors fail from UV degradation, from being mounted where they never get rain, and from wiring that has corroded. A sensor mounted under a soffit is decoration.

What a smart controller adds

• Weather-based scheduling. The controller adjusts run times based on actual local conditions — evapotranspiration data rather than a fixed schedule you set in April and forgot.
• Skipping after rain, automatically and by amount rather than simply on or off.
• Seasonal adjustment without anybody remembering to do it.
• Remote access, which is genuinely useful on a seasonal or rental property.
• Flow monitoring on some models, which catches a broken head or a cracked lateral before it runs for a month.

Soil moisture sensors

Arguably better than weather-based scheduling, because they measure the thing that actually matters — moisture in the root zone — rather than inferring it. They water on need rather than on prediction.

They need correct placement to work: in the root zone, in a representative part of the lawn, not next to a head and not in the driest corner.

What none of it fixes

A controller cannot correct uneven distribution. If half a zone gets twice the water of the other half, a smarter schedule still waters half of it wrongly — just more efficiently wrongly. The coverage audit comes first, always.

Restrictions still apply

Smart controllers can generally be configured to respect local watering day restrictions, and they should be. Restrictions change with drought conditions and a controller set once and forgotten will eventually be out of compliance.