He has adopted some of the principles of biodynamics, a form of farming in which livestock are treated with homeopathic remedies rather than antibiotics, and astronomical calendars and signs of the zodiac play a role in determining when to sow and harvest crops.

It is often derided by conventional farmers for being unscientific, producing low yields and being based on superstition. However, in recent years it has attracted keen interest because biodynamic produce also wins many prizes for quality.

“Biodynamics has a lot going for it,” said David Wilson, who manages the prince’s Duchy Home Farm, which lies close to his Highgrove estate in Gloucestershire. “We are beginning to use some of the principles to decide when we plant some vegetables. If the moon is waxing we plant some seed species and if the moon is waning, others.

“There is no doubt that if we plant certain seeds at the right phase of the moon they grow quicker and produce more vigorous plants.”

For some the prince’s latest move might evoke his revelation that he thought talking to plants helped them grow better.

There could, however, be a more practical interest at work because the growing reputation of biodynamic produce means it can attract premium prices.

Duchy Originals, the company set up by Charles to supply and market organic produce, already generates profits of more than £1m a year for his charities. A biodynamic line could boost profits further.

Biodynamic farming was founded early last century by Rudolf Steiner, an Austrian philosopher, scientist and social reformer. Steiner is best known for his schools, founded on the philosophy that the “whole child” should be nurtured.

His approach to farming was similar, and he taught that the sowing of crops should be timed to fit in with the cycles of the moon, planets and signs of the zodiac. Steiner’s Biodynamic Agricultural Association draws up a day-by-day timetable for planting. This is sent out annually to the 140 biodynamic farmers registered in Britain.

Under the Steiner system each crop type is linked to one of the four traditional elements: earth, water, wind and fire. Root crops such as carrots are seen as earth plants while fruits such as apples are linked with fire. Leaf crops, including lettuce, are associated with water.

Each crop type must then be planted on a day when the moon is in a sign of the zodiac associated with that element. Fruit, for example, might be planted when the moon is associated with Leo, a fire sign.

A spokesman for the prince said: “Some of the principles of biodynamics are being used at Duchy Home Farm, especially in growing vegetables. It is already an organic farm.

“The prince is committed to a virtuous circle of providing natural high-quality organic and pure products which help to protect and sustain the countryside and wildlife.”

Charles’s farm managers have been in regular contact with biodynamic practitioners including Denise and Ian Bell, who farm in Dorset. Denise said she was delighted at the move, adding: “We have been pushing for this for two years.”

Lord Haskins, a former adviser to Tony Blair on food and farming, said: “The (biodynamic) principles sound far-fetched but it would be justified if they can get a good price.”

Patrick Holden, director of the Soil Association, which promotes organic farming, and whose patron is Prince Charles, applies biodynamics on his own farm in Wales.

Holden said he accepted the lack of scientific evidence to support such an approach, but added: “That reflects the inadequacy of current tools for measuring such influences.”

Explore UK News

• Crime News

• Education News

• Health News

• Science News

• Scotland News

Times Recommends

• Olympic-size television coming to your town
• Mosley opens new front in battle for privacy
• Decorator fined for smoking in van