The subject of the study is the time series of the difference in electrical potentials along the trunk of a pine tree and the time series of meteorological and geomagnetic parameters consistent with them, measured by hardware and software complexes of the geophysical observatory "Petrozavodsk" and the Botanical Garden of Petrozavodsk State University in 2017-2022, as well as the time series of the K-index database global geomagnetic activity. The existence of characteristic regimes in the difference in electrical potentials of pine trees is shown, depending on the season, temperature, precipitation, humidity, determined by physical environmental factors and physiological processes in the tree. The reaction of the electrical potential difference of pine trees to meteorological parameters, thunderstorms, and space weather phenomena: magnetic storms and solar eclipses is analyzed. The results of these observations are qualitatively interpreted using known features of electric field of the Earth.