I built a Home Assistant add-on that turns the GARDENA smart Gateway (Art. 19005) into a standalone Matter device — the Matter stack runs directly on the gateway, so your GARDENA devices show up locally in Home Assistant (or any Matter fabric) without the GARDENA cloud and without a second server. Optionally it also publishes every sensor value over MQTT (HA MQTT discovery), so you get your devices two ways.
Install is a normal add-on flow — no SSH, no building, no flashing: add the repository, install, enter the device ID from the sticker, deploy. It installs into the gateway's writable overlay and is reversible (uninstall scripts included).
Honest status: this is a private hobby project, not affiliated with GARDENA/Husqvarna, use at your own risk. I can only verify it against the hardware I own — smart soil sensors + one SILENO mower. Everything else (Water Control / valves, pressure pump, smart power plug, other sensors/mowers) is modelled in code but not yet tested on real hardware. Apple Home / Google Home are untested.
What I'm looking for: testers — especially anyone with other GARDENA devices. The single most useful thing is data I can map a device from: the bridge's own log + a redacted snapshot of the device data layer (/var/lib/lemonbeatd/). The repo's Contributing page explains exactly what to capture and how to redact it. Bug reports and "it works / it doesn't" feedback are very welcome too.
Repo + one-click install: GitHub - wuselAUT/gardena-matter-mqtt-bridge: Cloud-free Matter & MQTT bridge for the GARDENA smart Gateway (19005) — runs on the gateway, no cloud. Home Assistant add-on. · GitHub 
Docs (EN/DE, with a language switcher): GARDENA Matter Bridge
BR wusel 