The water shortage this summer — the third season of drought in a row — is of particular concern to Linley. For having learnt, after the croquet episode, “not to be too bloody clever, and to grow things in harmony with the landscape”, he joined forces with the local mayor, Alain Cassan, who, with his son Benoît, is helping Linley get his land into ultimate harmony with the landscape.

Lavender fields — a purple summer blur when viewed from one angle, shifting to neatly domed rows abuzz with bees when you change your point of view — have been an essential part of the Provençal scene since well before the Impressionists and Van Gogh committed the sight to canvas.

“But so much is grown in China now,” explains Serena, “that the mayor came to us because he didn’t have enough output.”

The Cassans run the lavender distillery and aromatherapy laboratory in nearby Simiane-la- Rotonde (its round-ended abbey surrounded by lavender fields is one of the region’s postcard clichés), so their interest in turning the man who is 12th in line to the British throne into a lavender farmer was more than aesthetic.

Because they are at an altitude of about 600m, the Linleys are growing the multi-sprigged lavandin rather than the lavande fine whose essential oils are more redolent with healing properties, and cost much more, but which won’t flourish below 800m, as Benoît Cassan explains, adding that lavandin essential oil contains a goodly dash of camphor “pour chauffer les muscles”.

“I prefer lavandin,” says Serena. “It’s not so sickly in the bottle — and you get a lot more oil from the plant.”

This summer’s Linley lavender harvest of a handful of acres was taken straight to the distillery to be made into oil to perfume soap and washing powder. The additional fields that were newly planted earlier in the year show only the odd purple sprout.

Linley surveys the parched terrain with the heavy air of gloom and doom common to farmers the world over — “There’s another worry, all those parched trees are dying” — but finally pronounces of his crop: “I think it’s all right.”

All right it may well turn out to be, but until he increases his lavender acreage he’s hardly going to come out of it smelling of money. Benoît does the sums. “One hectare [nearly 2½ acres] yields five tons of plants. That gets you about 80kg of essential oil, and the price for the producer is €12 a kilo.”

But there is more than the sweet smell of £8 per kg to be made in Provence. The Linleys are making their property available for holiday rental. Although the pool is fenced, as French law for rented property demands, and there is an alarm that sounds if someone falls in, they’d prefer parties of adults to families with boisterous children. So far, they have concentrated on the refined upper reaches of the moneyed American market.

They won’t rent the main house and guesthouse separately — he imagines the horror of sharing: “Oi! Get out of the pool!” — and assures me that despite the winter cold, “there’s not really a month you wouldn’t want to come”.

With rates of about €5,500 (£3,760) a week in the high season, to include the daily services of Solange the housekeeper and property manager Sarah Morgan on hand to make sure everything runs smoothly, Linley claims that “it’s not that I’ll make an income. I’ll keep putting the money back in, to upgrade the roads and the forest”.

But, he adds, “like my father always says, make a place work”.

• For rental information,call Sarah Morgan, 00 33 490 755 316; www.davidlinley.com

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