A soil moisture sensor and a soil moisture sensing system are provided. The soil moisture sensor includes a double groove helical structure having grooves and formed from an insulator. The soil moisture sensor further includes at least a first electrode and a second electrode formed from one or more metals deposited at at least two different locations on the grooves. The soil moisture sensor also includes a processor for processing a soil moisture measurement signal based on a conductivity between the electrodes. The soil moisture sensor additionally includes a wireless transmitter for transmitting the soil moisture measurement signal to a remote location.