Extending BLE Range (not only) for Gardena Water Computers – and Measuring Whether You Actually Need to Water
If you're using a Gardena Smart Water Computer (or similar Bluetooth-only garden devices), you've probably run into the classic problem: the device sits outside near a tap, and your Home Assistant instance is nowhere close enough to reliably pick up the BLE advertisement.
The obvious fix is a BLE proxy closer to the garden – but once you're running a small ESP32-based device out there anyway, why not make it useful beyond just relaying Bluetooth packets?
That's exactly how this project came about. I wanted to extend BLE coverage to my water computer, but the sensor stick also ended up being the perfect companion device: it measures temperature, humidity, pressure, and air quality (IAQ via BME688/BSEC2) close to where the plants are. Plugged into an outdoor wall socket – think garage, garden shed, covered patio, or house wall – it sits sheltered but still close enough to the garden to deliver meaningful environmental data. That data feeds directly into automations that decide whether irrigation is actually needed – no point watering if it rained last night or humidity is already high.
The result is the ESPHome Air Quality Sensor Stick + Bluetooth Proxy, based on the ESP32-C6:
- Acts as a full ESPHome BLE proxy for nearby Bluetooth devices
- BME688 environmental sensor with BSEC2 IAQ accuracy tracking
- Runtime-configurable temperature offset (compensates for self-heating)
- NeoPixel status LED, plugs directly into a standard wall socket, compact stick form factor
- Fully open source – YAML packages structure, bilingual docs
GitHub: GitHub - STB3/esphome-BLE_proxy_envmon · GitHub
If you're interested in a ready-to-flash hardware unit, I've opened a pre-order campaign on Lectronz (small non-commercial community run, similar to how I handle the ESP-Sensostar boards):
Pre-order: ESPHome Air Quality Sensor Stick & Bluetooth Proxy by DIY store
Happy to answer questions. Would also love to hear if anyone else is using BLE proxies for garden automation!