Gardening by the Moon: Tradition Vs Science

In recent decades experiments have shown that the metabolism of plants, indicated by such things as their water absorption or oxygen metabolism, responds considerably to the monthly lunar cycle.  Two researchers at the University of Paris have shown that plant DNA changes in tune to this cycle.  Trees have electric fields around them, measurable by the potential gradient up the trunk.  Ralph Markson in the United States monitored this for years and showed how fortnightly and monthly lunar rhythms were present.

Animal oestrus (coming- on-heat) is cyclic, and yet traditions link animal fertility to the lunar cycle.  In the 2^nd century AD, the astronomer Claudius Ptolemy reported of the practical, hard-headed farmers of the Roman Empire that they notice the aspects of the Moon, when at full, in order to direct the copulation of their herds and flocks, and the setting of plants or sowing of seeds.  There is not an individual who considers these general precautions as impossible or unprofitable.

I have collected some years of data from a Thoroughbred stud farm, with dates of covering (bringing the stallion to the mare) plus recorded conceptions.  Mating takes place within just a few months in the spring of each year, which makes investigating the lunar cycle influence tricky.  Yet this data does clearly seem to show both increased fertility and increased coming-on-heat on the days around and just after the Full Moon.  If correct, this could have practical implications for horse breeding.

These investigations don’t always support traditional folklore in this area, but they tend to suggest that there is something in it.  They are relevant to beliefs such as that some part of the lunar month is best for pruning trees, i.e., the waning half, while the waxing half if better for grafting; or that calves should not be gelded around the Full Moon.

Applying the Theories

Do seeds germinate better at some point of the lunar cycle?  My experiments with seeds grown at constant temperature tended to confirm the results published by Lilly Kolisko in the late 1930s, namely that seeds would usually germinate better if sown around the Full Moon, and especially on the day or two prior to it.

There were some experiments conducted around 1940 by the John Innes Foundation, reported in what was then the Journal of the Royal Horticultural Society (RHS), to test Kolisko’s claims.  My view is that their results did in fact support Kolisko’s findings, but the report averred the contrary, prejudice against such notions being rather strong at that time.  Kolisko, who had emigrated from Germany in the 1930s, became disillusioned with the negative response to her research.

The vital question of how final crop yield is affected by sowing date has been thoroughly investigated within the bio-dynamic movement. However, deep disagreement exists amongst experts in this area.  For some decades now, Maria Thun has been reporting her results in her yearly Moon calendar, which apparently show weight-yields in accord with the elements of the sidereal or star-zodiac.

We are here asked to envisage four steps of crop growth: first the root (Earth), then the leafy shoots (Water) then the flowers with their airy fragrance (Air) and lastly the summer’s heat dries up the crop, maturing the seed (Fire).   Crops can be viewed as belonging to one of these elements, depending on whether they are a root, leaf, flower, or fruit/seed crop.  From this it follows that there is a proper lunar timetable appropriate for each crop.  For instance, potatoes, as a root-crop, grow best when they are sown as the Moon is passing in front of earth-element constellations (in the astrological zodiac).

This is, the pragmatic may object, more like some alchemical mandala than a scientific theory.  It is indeed simple, but does it work?  Is it really worthwhile – or indeed practical – for farmers to organize their work schedule around it?

In 1975, together with a market gardener, I started to test the theory, by successive crop rows sown over a lunar month.  Since then, British experiments on the topic have involved about five hundred rows sown of diverse vegetables.  I have published many of these results, and have reviewed the researches of others.  My view is that the theory stands up, and that Empedocles could not improve on it.

Not Everyone Agrees

A weighty German Bio-Dynamic textbook makes skeptical references to the Thun-model: the stars do not affect crop yields they say.  In view of the diversity of opinion on this matter, and the diverging instructions given in the lunar-gardening guides now on sale, we should perhaps consider more how plant growth varies in accord with the green fingers and even the expectations of the sower.

The Secret Life of Plants by Tompkins & Bird wasn’t just a hippy pipe-dream of the sixties, and plants are sensitive in ways we tend not to give them credit for.  But folklore ends and science begins when results are obtained that are repeatable.  Replications of the Thun effect – the classic Thun and Heinze results published in the early seventies describing eight years of potato-yields (1964 -71) are in my view sufficiently substantial for some such claim to be made.

Each year about one hundred thousand copies of the Thun calendar are sold world-wide, in 21 different languages.  The aim here has been to introduce the notion that all living things, including us, respond to the motions of the moon.  For growers to use a calendar based upon the moon may be a sensible idea.

Long ago, at the very dawn of British culture, before even Stonhenge, there were two stone circles at the heart of Avebury.  Both a hundred meters across, one was comprised of 29 huge stones and the other of 27.  These signified the two fundamental lunar cycles, as used today in a lunar gardening calendar.  They turn against each other: the 27-day orbit period, and its 29-day waxing and waning cycle.  Did Britons learn to count from these cycles?  Other cycles too are woven into a Moon calendar, and we can feel the turning of the wheel of life by using it through the seasons.