No. You can alternate a sensor among your plants. The Koubachi Plant Care Engine uses the time with the sensor to refine the care plan of each individual plant and considers this information even if you put the sensor to another plant.
We recommend leaving the sensor at a single plant for the duration of at least two completed water cycles (time from the first watering until the next watering) to guarantee an accurate adaptation of the Scientific Species Model. The longer you leave the sensor with a plant, the more our Plant Care Engine will learn from your data.
To take perfect care of your outdoor plants, we advise to use one device per plant.