IPPINKA Sustee Aquameter, Set of 4, Plant Soil Moisture Sensor, (Green, Large)

I received 4 of these soil sensor sticks to monitor the soil on either it's dry or wet. The sensor sticks start off white in the center. You carefully place the sensor stick into the soil near the plant carefully so you don't hit any roots then in a short period of time the white center will either stay white or blue. If it stays white you need to add water to your plant and if it turns blue you don't need to add water. To be honest I'm not sure if the sensor can turn blue day half way up being that soon you will need to add water. Mine stayed white so I watered as usual and the whole center turned blue. These take the guessing easy lol. They say each sensor last anywhere from 6-9 months then you need to replace. These that I have are medium in size which I feel is a good length . This size doesn't stick out too much . I highly recommend these water sensor sticks.