"Smart" Blumat Water Container with Home Assistant

Automatically water plants with physics and a simple water container thanks to the Blumat system. Additionally, detect if the water container is empty with Home Assistant and get notified.

"Smart" Blumat Water Container with Home Assistant
Water leak detection sensor used to detect if water container is empty

A few years ago I started to grow some plants on my balcony. I had multiple pods and it was tedious to water them all. I had to get the water from the kitchen and go through my living room to the balcony since we do not have water there.

The Blumat Trop System

I found a pretty elegant solution without any electronics and the need for a water connection (Though you can use this with a water tap as well!). Just the law of physics and no breaking electronics.

Advantages - Tropf-Blumat
Tropf-Blumat is an automatic watering system for plants all around the house. From flowering plants to your own vegetables, Tropf-Blumat is a needs-based system - watering only occurs when necessary.

Package of the Blumat Tropf System, Clay cones and water tube
Blumat System with a clay cone and some tube

I have installed this system for a few years now and it works great. I am using a 25-liter water container which is a little higher than the actual flower containers. That way I have enough pressure for about 3 meters of water tube.

Weekends and a week of vacation are no problem anymore.

Here are some pictures of our balcony with the system to give you an idea:


There are a few things you need to consider when using this.

You can not just install and run this system. It takes a few days until you have dialed in all the separate clay cones. Each plant may require more or less water and you have to dial them in. I would suggest about 2 weeks of tinkering.

If you install the system the first time that should be it. If you use it over the years as I did you may encounter problems with the tubing. The UV radiation from the sun will cook your tubing. They get brittle and tend to break and leak with 25 liters of water going down 🥲.


  • Bring those clay cones inside when winter is coming. Water might break them.
  • Same with the tubing. These can burst in winter due to ice.

Water detection for the container

Now let's get to the smart stuff that most people are here for. Even though I like this system since it can not fail in an electronic way. But we need to find a reason to put some electronics nearby right? Right? 🙃

But I have to solve a problem before doing that. So I always miss filling the water container. And you should not run those clay cones dry.

Therefore I first thought of a water level sensor but did not find anything. But honestly, I do not need the exact water level. I just need to know when a specific amount is left. Then I browsed the internet and found the Aqara leak detection sensor.

Aqara Leak Sensor
Aqara Leak Sensor

This sensor has 2 metal probes at the bottom. You can just attach any wires to them via the 2 screws. Then I found a place to mount that thing and it was hammer time.

After hammer time I check how long these leads need to be, cut them to the right length, and attached some ferrule to the leads to prevent them from contacting themself. This prevents false dry detection.

In Home Assistant I have a fairly simple automation to notify my girlfriend's smartphone via the Home Assistant App:

alias: Benachrichtigung fuer Wasser alle!
description: ''
  - type: not_moist
    platform: device
    device_id: c9de3c7b3248755e6f4cc9f38f386e8e
    entity_id: binary_sensor.wasserkanister_water_leak
    domain: binary_sensor
      hours: 0
      minutes: 0
      seconds: 0
condition: []
  - service: notify.mobile_app_nokia_6_1
      message: Ich hab Durst! 🚱
      title: 💧 Wasserkanister 🌱
mode: single
Home Assistant Automation for leak sensor

Not too much logic I would say.

Did you find that useful? Let me know in the comments and share this with likeminded nerds 🤓

That is it, I wish you a great day!