You may notice that soil moisture might fluctuate erratically either immediately after or during watering. Generally, you can expect moisture data to be less stable above 45% because the Spruce Sensor has been optimized to measure soil water content below field capacity or soil moisture saturation. Sensor readings will stabilize as moisture decreases below saturation, or around 30%-40%, depending on soil type.
Moisture data fluctuation during or after watering can be due to a variety of factors, including:
- Extremely dry soil: Excessively dry and packed soil will cause water to pool at the soil surface, causing unpredictable absorption into the soil and therefore, unpredictable moisture data. It is also possible that the pooled water will drain and run down the length of the probe, which will skew soil moisture readings.
- Soil density: Spruce measures volumetric water content in the immediate vicinity of the sensor. If the soil around the probe is non-uniform, this may cause moisture data output to be more noisy.
- Drainage: Poor drainage can result in non-uniform absorption into the soil.