my electronic design hobby at its peak, I followed a lot of rabbit trails. One of my discoveries was that all plants carry a 0.4V charge relative to the ground. This seemed to be generated by the plants themselves. But most plants have a common ground -- therefore I grounded them separately (above) so as to wire them in series and run 1.5V micro-power circuits off pot plants. This worked well. OBSERVATION: I succeeded, too, in running a germanium oscillator off a single plant, which could potentially step up the voltage and create as many grounds as desired. I did not however get beyond the oscillator stage. I think, though, that somebody else could, with advanced knowledge of micro-power circuits.