Effect of Artificial Light on the Growth of Plants

Abstract

THE effect of light on plant life has been the subject of many scientific investigations. So long ago as 1880 Siemens showed that continuous exposure to arc lamps promoted luxuriance of foliage, greater intensity of colouring, and more rapid ripening of fruit. It is common knowledge that plants grown in partial shade are apt to be weakly, and that the flowers, if produced, have in general a fainter shade of colour. Other examples were mentioned by Schübeler in a communication to the British Association in 1881. The extraordinary rapid growth of vegetation in the Arctic regions during the period of uninterrupted daylight has been the subject of comment; likewise the rapid ripening of corn in regions of Norway and Sweden where the summer does not exceed two months, but where, during this period, the sun scarcely sets.