The present invention is directed to an apparatus and a process which is low-cost, simple to use, reliable and long-lived and will effectively monitor the moisture condition of a volume of soil. In accordance with the invention, a light transmitting rod is placed into the soil so that its lower end is within the soil and its upper end is visible from outside the soil volume. The lower end of the rod is beveled to reflect light entering the rod from its upper end back toward the upper end. In accordance with the method of the present invention, observance of the presence or absence of light at the upper end of the rod determines the moisture content of the soil. That is, the presence of light confirms that the soil is dry, whereas the absence of light (a dark end) confirms that the soil is moist. In accordance with the apparatus of the present invention, the rod is placed into the soil and a light sensor is placed adjacent to or on the upper end of the rod to control a pump or valve for providing water to the soil. <IMAGE>
