Chronobiological Investigations of Crops Grown under Biodynamic Management. I. Experiments with Seeding Dates to Ascertain the Effects of Lunar Rhythms on the Growth of Winter Rye (Secale cereale, cv. Nomaro)

The relationship between the position of the moon and crop growth is an issue that was viewed as being of great consequence in antiquity but has become controversial or viewed as superstitious in our time. In 1924 Rudolf Steiner, the founder of biodynamic farming, suggested that healthy agriculture should not only consider factors such as crop rotations, sound stocking rates, and organic manuring, but also cosmic factors. Based on his observations he indicated a relationship between the position of the moon relative to the sun (synodic rhythm), planting dates, and crop growth. A number of studies were carried out in the 1930's and 1940's to test this relationship; these studies produced varying results. Recent studies by biodynamic workers M. and M.K. Thun (1963 ff.) have indicated a relationship between the position of the moon relative to the zodiac (sidereal rhythms), planting dates and crop growth. These results have become popularized by the publication of calendars and research reports. The result is that in some circles biodynamics is equated with planting by sidereal rhythms. In this paper research is described that tests the relationships between lunar rhythms (especially the sidereal rhythm described by Thun and Thun), seeding dates, and the growth and formation of yield of winter rye. Rhythms were tested by observing the effects of seeding winter rye at different autumn planting dates (16–20 dates/month) in the context of replicated, randomized complete block type experiments. The experiments took place over an eight-year period on a biodynamic farm near Frankfurt in West Germany. Results were used to calculate polynomial regressions for different parameters of crop performance against seeding dates. Curves fitted from these regressions were used to indicate general trends associated with the dominating primary growth factors such as weather. The magnitudes of effects associated with planting at a specific lunar position were measured by the deviations from the trend curve. Average deviations for such positions were calculated using data from the multi-year trials. The largest effects of lunar influences were apparent during early growth stages, and especially at emergence. Early influences on the formation of yield were modified by compensatory mechanisms so that little effect was found on yield. Nevertheless, lunar influences were still apparent in the crude protein content of the rye grain. The effects of lunar rhythms were weak and in accordance with previously described reports in the literature on the effects of synodic and anomalistic rhythms. The effects of the sidereal rhythms described by Thun and Thun were not apparent.