A real Christmas tree with glowing candles is a cherished tradition for many during the holiday season. However, dry trees not only pose a significant fire hazard but also shed their needles more quickly, diminishing the festive ambiance. To address this issue, I developed an automated watering system that continuously hydrates the tree. This keeps the tree fresh for longer and significantly reduces the fire risk associated with real candles.

At the core of this system is an Arduino Nano, connected to a water level sensor and a small 5V submersible pump. The sensor monitors the water level in the tree stand and sends a signal when the level is too low. To avoid frequent and potentially annoying pump activations, the water level is checked only once per hour. If the water level is indeed too low, the Arduino activates the pump, which refills the water until the sensor indicates the level is sufficient.

For added safety, the system ensures that the pump never runs for more than ten seconds, even if the sensor continues to signal a low water level. This limitation prevents flooding in case of a sensor failure or malfunction. The ten-second runtime is sufficient to refill the water level in most standard Christmas tree stands.

The technical implementation is straightforward and efficient. The 5V submersible pump, with a flow rate of 100 liters per hour and a power consumption of just 200 milliamps, is controlled via a MOSFET. The system is powered through a USB cable, making it highly adaptable to various USB power sources, such as a smartphone charger or power bank. The water level sensor operates as a float switch, detecting whether the water level is low or sufficient. When the sensor detects low water, the Arduino turns on the pump until the water level is restored or the safety cutoff activates.

This system offers the added benefit of easy installation. The Arduino Nano, pump, and sensor can be seamlessly integrated into the tree stand without requiring advanced technical skills. The system is quiet, efficient, and fully automatic, allowing you to focus on enjoying the holiday season.

A well-hydrated tree not only lasts longer but also significantly reduces the fire risk – especially crucial when using real candles. This automated watering system enhances safety, extends the tree’s freshness, and provides peace of mind during the holiday season. A small technical project with a big impact for a safe and joyful Christmas celebration!

List of Material

5 V submersible pump
https://www.pollin.de/p/tauchpumpe-3-5v-stehend-330136

Water level sensor
https://www.pollin.de/p/schwimmerschalter-pns-43-10w-550999

Arduino Nano
https://amzn.to/3ZkDZB3

MOSFET
https://amzn.to/4fCJKzH

PETG black
https://amzn.to/3PjboGX