🌱 Overview
Steffen Berthold turned his wanderlust – and as he says, his "lazy gardener style" – into the inspiration for a fully automatic irrigation system. The goal: to keep plants on the rooftop terrace, in raised beds, and in the large garden healthy without daily manual watering – controlled and monitored with Shelly devices.
🏗 The setup
The system combines four Shelly devices, Home Assistant, and smart irrigation technology into a multi-zone network:
Shelly Plug S – controls valves for rooftop and raised bed irrigation.
Shelly 2PM – powers a pump in the underground rainwater tank and measures consumption.
Gardena distributor – controls up to six irrigation lines per zone.
ESP32 microcontroller and sensors – make the setup smarter by monitoring water level, pressure, and temperature.
💧 Three-stage irrigation concept:
1️⃣ Rooftop Terrace:
A simple system with a Shelly Plug S that opens or closes a valve for micro-irrigation – ideal for balcony plants.
2️⃣ Raised Bed:
An advanced system with an additional Shelly Plug S, an electric valve, and a Gardena distributor that supplies six individual irrigation lines for around 120 plants.
3️⃣ Garden:
The most complex zone: with a Kärcher BP2 cistern pump in the underground rainwater tank, controlled by a Shelly 2PM. Sensors monitor water level, pressure, and leaks. Home Assistant coordinates pump and valve times.
📲 How it works:
Schedules or manual triggers in the Home Assistant dashboard start the irrigation.
The Shelly Plug S or Shelly 2PM activates valves or pump, timers control the runtime per irrigation line.
Sensors provide real-time data – and stop the system in case of dry run, leaks, or empty tank.
Weather data prevents irrigation on rainy days. Float switches in the tank secure water reserves.
⚡ Why Shelly?
Steffen relies on Shelly for flexibility, reliability, and integration with Home Assistant:
More than 200 Shelly devices control his home – including lights, shutters, relays, and sensors.
Local control ensures the system works even without Home Assistant.
Support and durability matter: Only two devices failed in two years – one of which was replaced under warranty.
🌟 The result
Effortless gardening: Plants stay well cared for even when away.
Sustainable irrigation: Rainwater from the underground tank is used before tap water.
Smart control: Weather-dependent schedules, leak detection, and zone-based control.
Clean installation: Pipes, pumps, and cables are mostly buried or neatly installed – for a tidy garden.
This project shows that Shelly devices impress not only in smart homes but also in smart gardens. With a mix of DIY creativity and Shelly automation, Steffen has created an efficient, scalable, and elegantly integrated irrigation system.
