Effect of Light and Water on Schefflera Plant Electrical Properties

The electrical parameters of Schefflera arboricola as a function of time and plant water uptake were monitored and reported here. Electrodes clamped and attached to the plant leaf, stem and soil along with a temperature sensor, a light sensor and a 10 GHz microwave sensor were used to simultaneously measure the electromagnetic properties of the plant and relate it to water uptake, light level, and temperature. The data collected was correlated with light intensity, temperature and moisture content of the soil. The leaf capacitance periodically decreased by 51 pF/hr during the night and increased by 62.3 pF/hr during the day. The plant stem capacitance, on the other hand, decreased by 0.8 pF/hr at night and increased by 18 pF/hr during the day. Its resistance increased by 3.6 KΩ/hr at night and decreased by 92.3 KΩ/hr during the day. The microwave reflection also changed periodically during the night and day. These experiments were repeated over extended period of time (4 days) with watering and drought cycles. The wet and the dry phases for the measurements gave distinct signature data that can be used to devise a sensor to optimize watering of the plant.