A system monitors growth characteristics of a plant having a root buried in a prescribedvolume of ground using a plurality of electrodes inserted into the ground at aknown spacing relative to one another in proximity to the root or root-like structure.When electrical current is applied to some of the electrodes, electrical potentialis measured at other ones of the electrodes to construct a representation of electricalimpedance across the prescribed volume locating the root or root-like structure.Growth characteristics of the soil and the plant, for example root size, rootshape, soil moisture content, and the like, can be identified by locating variationsof the electrical impedance.
