LoRaWAN Irrigation Control Systems

Why Automate Irrigation

Most irrigation runs on fixed schedules. "4 hours every 3 days" regardless of whether it rained yesterday or the soil is already saturated. It's simple to program but wasteful.

I've measured this: soil moisture-based control cuts water use by 30-50% compared to fixed schedules. Crops get water when they actually need it, not when the timer says so. Plants do better, water bills drop, and you stop irrigating during rainstorms. Simple upgrade, significant impact.

System Components

Sensors:

• Soil moisture probes (capacitive or TDR) at root depth
• Temperature sensors (soil + air) for ET calculation
• Rain gauges to skip irrigation after precipitation
• Optional: soil EC sensors for salinity monitoring

Controllers:

• LoRaWAN solenoid valve actuators (12V/24V)
• Pulse counters for flow metering
• Battery or solar powered operation
• 5-10 year battery life typical

Network:

• LoRaWAN gateway (5-15km range)
• Network server (ChirpStack, TTN, or commercial)
• InfluxDB + Grafana for visualization
• Logic engine for automated control rules

Control Strategies

Soil moisture thresholds: Open valve when moisture drops below setpoint (e.g., 25% VWC). Close when target reached (e.g., 35% VWC). Simple and reliable.

ET-based scheduling: Calculate daily water deficit from temperature, humidity, solar radiation. Irrigate to replace deficit. More complex but handles varying crop stages.

Multi-zone optimization: Different crop types or soil conditions need different schedules. LoRaWAN allows individual zone control across large areas without trenching control wires.

Typical Applications

Vineyards: Controlled water stress during certain growth stages improves grape quality (higher sugar concentration). Soil moisture sensors at multiple depths prevent over/under watering.

Orchards: Drip irrigation systems with soil moisture monitoring. Large areas (50+ hectares) benefit from LoRaWAN's range - no need for cellular coverage or trenched control cables.

Row crops: Center pivot or linear move systems can integrate LoRaWAN soil moisture sensors to trigger automatic start/stop based on field conditions.

Greenhouses: Multiple irrigation zones with individual moisture/temperature monitoring. Automated fertigation control based on plant growth stages.

Hardware Selection

Soil moisture sensors: Capacitive sensors (5-50 EUR each) are fine for most applications. TDR sensors (200-500 EUR) needed for research or high-precision requirements. Place at crop root depth - typically 30-60cm.

Valve controllers: Latching solenoid valves draw power only during state change - better for battery operation. Non-latching need continuous power to stay open. LoRaWAN valve controllers: 100-200 EUR typical.

LoRaWAN gateway: Indoor gateway fine if fields are within 2-5km. Outdoor gateway with elevated antenna can cover 50+ hectares. Range depends on terrain and crop canopy.

Common Mistakes

Wrong sensor placement: Sensors too close to drip emitters or sprinkler heads give misleading readings. Place between emitters where roots actually grow.

Single-point sensing: One sensor per 5+ hectare field is useless. Soil variability means you need multiple sensors to understand actual conditions.

No flow metering: You need to know how much water actually got delivered. Broken pipes, clogged emitters, or valve failures are invisible without flow meters.

What I Provide

Services:

• System design and sensor placement planning
• Hardware specification and sourcing guidance
• LoRaWAN network setup
• Control logic programming
• Dashboard and alerting configuration

You own everything:

• Complete source code for control algorithms
• Self-hosted infrastructure
• All system documentation
• No monthly fees after implementation