Former motor racing champion Jody Scheckter and his Hampshire pile, Laverstoke Park

Standing at the entrance to the Laverstoke Park Estate is a striking blue and green sign, clearly painted by a child. It shows a cheery, potato-headed gentleman in turquoise shirt and braces, sporting an emerald-coloured tie that matches the fields behind him.

The artist responsible for this creation is four-year-old Freddie Scheckter, and the smiling figure in the picture is his dad Jody, the South African-born firebrand who in 1979 was world motor racing champion, but has since been transformed into the very model of a land-owning English country gentleman.

To anyone who knew Scheckter in his Formula One days, the placid-looking figure in the painting bears little resemblance to the swarthily-sideburned hothead who caused such a massive pile-up in the 1973 British Grand Prix that half the field had to withdraw.

The fierce, young buccaneering features at age 22 have mellowed into the altogether more avuncular contours of a 55-year-old father of six (he has two children from his first marriage and four with his English-born second wife, Clare).

So has the beast become a lamb? You might think so initially, but after an hour or so touring the estate in his company, you realise that he has thrown himself into his new career, of organic farmer and landowner, with the same intensity as he used to grip the steering wheel of his Ferrari.

"Everything - and I cannot stress this too strongly - everything begins with the soil," he declares. "Do you know that in one spadeful of soil there are more living organisms than there are people on this planet? We believe that healthy soil makes for healthy grass which makes for healthy animals, which in turn makes for healthy meat and milk and therefore healthy people who eat that meat and drink that milk".

Only thing it doesn't make at present is money. It is 10 years since the Scheckters bought Laverstoke, and so far the cash flow has been pretty much one-way. The list of outgoings reads as follows: complete restoration of one grand 17th-century mansion; construction of one new farm shop, one dairy processing unit, one abattoir and one compost production unit; rearing of 27 pure native Aberdeen Angus cattle, 65 Jersey cows, 135 pure Herefords, 350 water buffalo, 750 "other breed" bovines, 2,000 sheep, assorted wild boar and rare-breed pigs; general upkeep of 2,500 acres and wages for 35 staff.

"Most conventional farms operate with just a handful of workers, but because organic is so labour-intensive, we need people on site, and on hand", says Farmer Scheckter. "Most of them actually live here, too. We've got 21 properties dotted around the estate - little lodges and cottages - and they're all full of Laverstoke employees. Which means that, unlike most big farms, we can't generate income from renting out property."

In fact, pretty much the only revenue stream they can divert through the gates is the steady trickle of cash that comes in via the farm shop. Here, members of the public can help Squire Scheckter shoulder some of the costs of super-ethical, ultra-organic, pesticide-free farming by paying £3.75 per lb for chickens and £20 per lb for fillet steak. Twice as delicious as from a supermarket, admittedly - but three times the price.

And then there's the house. "All I can say is that there's a lot of crooks at the high end of the restoration market, and we've come across more than our fair share," he grumbles. "We're talking about a project that's three years behind schedule, 130 per cent over budget and hasn't resulted in any visible improvements."

In normal circumstances, bankruptcy might be on the horizon - but the Scheckter pockets are deep. Estimates of his personal wealth hover round the £90-100m mark; figures that he won't confirm or deny, though he declares with playful outrage that he merits a far higher ranking than his current 443rd place in the British rich list.

The bulk of that money was made not from motor racing, but from the 12 years he spent building up his firearms training business. "I came up with a way of creating a realistic training simulation system using lasers rather than bullets", he explains. "As someone who was used to preparing for a dangerous activity such as motor racing, I was able to put myself in the position of a soldier preparing for battle. But the reason we became the industry leaders was because we made use of the latest technology available - which is exactly what I'm trying to do here at Laverstoke, only applying it to traditional, pesticide-free farming methods that stood us in good stead for centuries."

And although breaking-even is still a distant dream (at least two years away, he says), there's no question of the Scheckters upping sticks and leaving Laverstoke. "You see that?" he says, pointing to the picture. "We'd spent a fortune having a logo professionally designed, and we dropped it for that painting, because it's an honest picture. That's what we are here."

Laverstoke Park, Overton, Hampshire (01256 772800; www.laverstokepark.co.uk)