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A capacitive sensor for soil-water monitoring was developed using a two-plate capacitor and an oscillator. The capacitor was built by placing two parallel fiberglass circuit boards coated with by-component automotive varnish 5 mm apart. The resistance produced by the varnish coating was of the order of 106 .. The capacitor, together with resistors the IC 74LS122N (Retriggerable Monostable Multivibrators) was designed as an RC oscillator. The output of the 74LS122 was directed to a 12 Stage Ripple Carry Binary Counter/Divider (TC4040BP) In order to remove any addictive effect from wires, the circuit was installed directly at the capacitor boards. Two sensors were installed on a block of soil installed at one side of a suspended scale and reading from the sensors, from a load cell and from a temperature sensor were taken daily at 8:00, 11:00, 13:00 and 15:00 Oclock for 63 days continuously. Results from calibration displayed a third degree polynomial correlation between frequency output and volumetric moisture content with R2 above 0.985 for both capacitive sensors. The frequency output of the sensors presented a sensibility to room temperature variation as the temperature produced a reduction on the output frequency of the sensors. However, a regression analysis in a temperature dependant model of the data demonstrated no statistical significance of temperature on the response of the sensors.