Can lunar planting help your garden grow?

For millennia, humans have planted and harvested crops according to the phases of the moon. The idea that the moon exerts a determinable influence on plant and crop growth is common to the folklore of many ancient societies, from the Celts of early Britain to the Maori in New Zealand.

Roman historian Pliny the Elder (AD 23-79) gives a lengthy account in his Natural History on how to regulate agricultural activities according to moon cycles. Whether it was the Babylonians timing their harvests by the sign the moon travelled through, or the farmers of Eastern Europe watching each moon phase and consulting their almanacs for the best time to plant, earth’s celestial companion has always been thought a heavenly indicator of the seasons for growth.

Rediscovering the moon

Traditional methods of horticulture using lunar gardening were stifled by the new “scientific” philosophy that arrived in the late 17th century. Today, however, there is a resurgent belief in the benefits of gardening by the moon. In a reaction against the increasingly technological approach of modern times, a growing number of people are seeking to become more attuned to nature’s rhythms. Others, including both small-scale and commercial growers, simply want to discover what benefits a lunar gardening schedule may offer.

In the UK, the prestigious BBC Radio 4 network recently addressed the subject of lunar planting in their Sunday program, Gardeners’ Question Time, in an interview with John Harris, head gardener at Tresillian House Garden in Cornwall and award-winning author of R.J.Harris’s Moon Gardening. Following a lunar planting regime since the 1960s, Harris swears by the technique, never sowing a seed without first checking with his lunar calendar.

“The ancient Chinese, Greeks and Romans were guided by the moon,” Harris says. “I find it very effective to time my sowing, planting and pruning by the moon. By applying fertiliser at the right time, I can cut my fertiliser requirement by 50 per cent. It’s not folklore; it’s practical knowledge that works. People call me the ‘loony gardener’ but I don’t mind.”

The secret of Harris’s success lies not only in his use of the deep-bed trough in which he plants the flowers, but also his regular consultation of a moon chart. In Australia as well as many other countries, moon charts or lunar calendars are available to farmers and gardeners and there’s now considerable evidence that crops can benefit from the correct use of such guides. According to Thomas Zimmer, astrologer, gardener and creator of Australia’s popular Astrological Calendar and Moon Planting Guide, this practice is based on an age-old observation that the moon is a regulator of growth processes on earth.

More than the sun

“Planting by the moon (or lunar agriculture) is a simple method of planning your activities in the garden — seed sowing and plant propagation especially — to take place at certain times of the lunar month,” Zimmer says. “By adapting their gardening timetable to coincide with this natural monthly rhythm, growers can not only organise the various tasks that have to be done on a recurring basis, but can also achieve better germination rates, more vital plants and superior-quality produce.”

Zimmer further points out that his calendar is designed to “overcome a flaw or deficiency in the conventional system of reckoning, which, as we know, is based solely on the sun… The solar calendar (of Roman origin) works perfectly to align the dates with the seasons but makes no mention of the moon,” he says.

Before the advent of the Roman calendar, the lunar calendar had been well established, but this too had problems with fluctuations. The Zimmer calendar offers a solution by incorporating both calendars — that is, the standard calendar with the lunar calendar surrounding it in an outer circle.

Of course, adhering to a lunar gardening regime does not obviate the necessity to implement and maintain best-practice gardening methods. Also warns Zimmer, “Don’t lose sight of the seasonal limits when a crop can be grown — moon planting only tells you which days within a given season are best.”

Lunar influence

It’s well known that the moon’s orbit around our planet affects the rising and falling of tides, air currents on the earth’s surface and the occurrence of thunderstorms. Tide cycles in particular follow the same cycle as the rising moon in lakes and rivers as well as oceans. At first glance, it may seem there’s little association between the correlation of moon and tide and planting or gardening, but it must be remembered that the earth’s below-ground water content responds to the same tide cycle as the huge expanses of water covering our planet.

Put simply, the moon’s magnetic force pulls everything containing water. Every gardener understands how important the soil’s water content is to a germinating seed. It would naturally follow that, in order to give seeds the best chance to germinate, grow and develop, consideration should also be given to the pull of the moon.

Studies have also shown that the moon is capable of affecting the surface of the earth. In 1970, a Columbia University study across the continental United States measured earth tides and found that land surface changes at an average of 12 inches per day. Lunar winds, tides, earth tides and rainfall together with the lunar effects on the patterns of thunderstorms are all examples of the effect of the moon on our planet and on growing things in particular.

Waxing and waning

Essentially, the lunar month is divided into two periods: waxing and waning. The new and full moon herald the beginning of each period. The theory is that increasing moonlight is best for annuals that bear their fruit above the ground, and decreasing moonlight is more favourable for root crops.

The waxing moon is its period of growth from new to full. This is when the moisture content of the soil is at its highest and is the most advisable time for planting. The first week is the best time to plant crops that have their seeds on the outside, and the second week (between the first quarter and the full moon) is best for crops that produce seeds on the inside.

The waning moon occurs during the full to new moon (last quarter). This is when moisture content in the soil is at its lowest. There’s less sap rising in trees and shrubs and it’s an ideal time for pruning. Root crops are best planted at this time. According to Thomas Zimmer, “The third week sees the moon decreasing in light … By sowing root crops now you get better production below ground. Plant beetroot, potatoes, parsnip, carrots, onion, sweet potatoes, turnips, radish, garlic, ginger, chicory etc. Likewise, sow or strike all perennials now — any plant that grows after a period of winter dormancy. It is the root system in these cases which determines long-term viability of the plant.”

In short, the waxing moon is the time to encourage rapid new growth. Says Zimmer, “The new moon begins the first week of the gardener’s month. The crops that will do best here are the leafy annuals including the cabbage family, celery, lettuce, spinach, silverbeet, asparagus, artichokes, fennel, parsley, basil, cress, dill and coriander.”

If it’s necessary to control or retard growth, these activities should be performed during the last week of the waning moon or fourth quarter. It must also be taken into account that the days of full and new moon are considered “barren”, indicating no planting should be attempted at this time. As the moon revolves around the earth every 28 days, different amounts of sunlight are reflected according to its angle towards the sun. The intermediate phases between the new moon, first quarter, full moon and last quarter are called crescent and gibbous and are further subdivisions of these phases.

According to the system, account is also taken of the relationship of the moon to the zodiac and its 12 signs. In the zodiac, each of the four elements rules three signs. Aries, Leo and Sagittarius are the fire signs; Taurus, Virgo and Capricorn are ruled by earth; Gemini, Libra and Aquarius by air; and Cancer, Scorpio and Pisces by water. Water signs are thought the most fertile and fecund, so the best time for sowing of seed is when the moon passes any of these signs. The fire signs are considered the least fertile signs, as they are dry and barren.

Folklore or science?

So is there a scientific basis to support lunar planting theory? Dr Nick Kollerstrom, author of Planting by the Moon, is a science historian who became convinced of the benefits of lunar planting in the 70s while working on a biodynamic farm in the UK. He believes the system has been bypassed by modern science for far too long.

“I believe the moon affects us here on earth,” he says, “but I think it has a rather more intense effect on plants than it does on us.” Kollerstrom has found that sowing around the time of the full moon brings on faster germination but as yet has no evidence of an increase in yield. Biodynamic farmers, according to Dr Kollerstrom, have been using the lunar calendar for the past half-century. “Now it’s a worldwide movement and their results in yields and rhythms of growth are worth taking account of.”

The biodynamic movement is based on the work of Rudolf Steiner, a visionary in his field, who, as early as 1923, predicted the relatively recent BSE (“mad cow”) crisis.

Systematic investigation into how the time of sowing affects final growth really began with the experiments in the 1950s by German biodynamic farmer Maria Thun, now publisher of the Stella Natura agricultural calendar. Examining ancient and mediaeval theories of planting by the zodiac, Thun began to work with them in experimental conditions. She concluded that each plant is composed of four essential parts: leaf, root, flower and fruit or seed. Each plant is cultivated to yield one of the four qualities. Tomatoes, for example, are a fruit or seed crop; nasturtiums are a flower crop.

Each of the four essential plant parts is ruled by an essential element. According to Thun’s model, leaves are ruled by water, roots by earth, flowers by air and fruit by seed or fire. Plants, therefore, are sown according to the corresponding element of the zodiac through which the moon is passing.

Thun’s method was to sow one row of seeds every few days each time the moon reached the middle of a new zodiac constellation. Thus 12 rows were sown in the course of one revolution of the moon around the zodiac. She allowed each row to grow for the same period of time and, after harvesting, the weights of the crops from each row were compared.

Results for potatoes showed that maximum yields occurred in the three rows sown on root days, ie when the moon was standing in front of one of the three zodiac constellations traditionally associated with the element of earth. Conversely, when the moon faced one of the water constellations, minimum yields tended to occur. Achieved yield increases were around 30 per cent for the three earth element signs compared with the other nine.

Planting chart according to Thun’s model