A probe sensor for directly measuring electrical conductivity ("EC") of a soil, the probe sensor comprising: a tube having an outer wall and an inner wall; an EC board mounted on the tube; a microprocessor mounted on the EC board; characterised by radio frequency ("RF") transformers, each RF transformer comprising a respective primary and a respective secondary; wherein each respective primary comprises a respective sleeve positioned on the exterior of the outer wall of the tube for direct contact with the soil, wherein each respective sleeve defines two longitudinal slots, on opposing sides of the tube, and wherein each respective sleeve is electrically coupled to the EC board; wherein each respective secondary is wound on a respective substantially temperature-stable, non-electrically-conductive bobbin, is positioned within the inner wall in alignment with slots of a respective sleeve, and is electrically coupled to the EC board; and wherein the RF transformers are configured to sense changes in a load by the primaries of the RF transformers; a plurality of temperature sensors mounted on the tube interposed between the inner wall and the outer wall of the tube, wherein each of the plurality of temperature sensors is positioned proximate to a respective sleeve, wherein each temperature sensor is electrically coupled to the microprocessor; and a plurality of moisture sensors mounted on the tube interposed between the inner wall and the outer wall of the tube, wherein each of the plurality of moisture sensors is positioned proximate to a respective sleeve, wherein each moisture sensor is electrically coupled to the microprocessor. a tube having an outer wall and an inner wall; an EC board mounted on the tube; a microprocessor mounted on the EC board; characterised by radio frequency ("RF") transformers, each RF transformer comprising a respective primary and a respective secondary; wherein each respective primary comprises a respective sleeve positioned on the exterior of the outer wall of the tube for direct contact with the soil, wherein each respective sleeve defines two longitudinal slots, on opposing sides of the tube, and wherein each respective sleeve is electrically coupled to the EC board; wherein each respective secondary is wound on a respective substantially temperature-stable, non-electrically-conductive bobbin, is positioned within the inner wall in alignment with slots of a respective sleeve, and is electrically coupled to the EC board; and wherein the RF transformers are configured to sense changes in a load by the primaries of the RF transformers; a plurality of temperature sensors mounted on the tube interposed between the inner wall and the outer wall of the tube, wherein each of the plurality of temperature sensors is positioned proximate to a respective sleeve, wherein each temperature sensor is electrically coupled to the microprocessor; and a plurality of moisture sensors mounted on the tube interposed between the inner wall and the outer wall of the tube, wherein each of the plurality of moisture sensors is positioned proximate to a respective sleeve, wherein each moisture sensor is electrically coupled to the microprocessor.