A quiet revolution is taking place in the orchards of the Western Cape. After decades of trying to coax fruit onto the trees with the aid of chemicals, fruit farmers are packing in the pesticides and deciding to grow green.

Organic farming has come to South Africa, where it is being billed, not only as a profitable enterprise, but as a panacea for poor soil quality in growing regions.

From an estimated five million rand before 2003, sales of organic food grown in South Africa - domestic sales and exports combined - jumped to R155m in 2005, with an exponential increase expected again in 2006/2007, according to Organics South Africa trade organisation.

After a slow start the rate of conversion to organic farming has accelerated. Of the 230 certified organic or in-conversion operations in South Africa in 2005, 75% have started organic processes in the previous two years.

South African retailers are also, belatedly, falling in behind organics. Organic tomatoes, apples and potatoes are now widely available in supermarkets, from the mass-market Pick 'n Pay and Checkers chains to Woolworths.

In an emerging market such as South Africa the move to organic production is usually a economic rather than an ideologically-driven decision.

Cheap labour

With the global market for organic food growing at a runaway 35%, new suppliers are being urgently sought, particularly in Europe and the United States.

In these markets, high labour costs act as a deterrent to a shift to organic farming. South African farmers, on the other hand, have access to a large pool of cheap labour. With a minimum wage of R885 a month for farm workers in rural areas, most commercial farmers can afford several pairs of hands when it comes to weeding.

For Modderfontein Farm's Mike Stekhoven the shift to organics on his 2 500-hectare farm two hours north of Cape Town was the only way to secure future profitability.

"I'm a businessman," he says. "Conventional farming offers no return."

The citrus industry, like the wine industry, is periodically beset by gluts in production, pushing down prices and squeezing producers' margins.

Stekhoven produces 56 hectares of citrus and 130 hectares of rooibos tea on 800 hectares of arable land, with plans to expand the citrus crop to 100 hectares.

Although five years after beginning the conversion to organic, Modderfontein's citrus crops are still a fraction of what they used to be, Stekhoven estimates that the profits, when they come, will be mouthwatering.

Apart from higher prices for organics, farmers in the Western Cape give another reason for eschewing conventional agriculture: decades of heavy nitrate and fertiliser usage has robbed the already poor soil of its nutrients.

Killing off friendly bacteria

Hennie Saaiman, a potato farmer-turned consultant on biological agriculture, notes that in the late 1970s, 20kg of nitrates were recommended to secure two tons of wheat in South Africa. Today, to obtain the same yield requires an input of 55kg.

"If we hadn't made that change (to organic farming) we wouldn't still be here," says Mike Prevost, owner of Lorraine Farm in the Elgin Valley, who pioneered the production of organic apples and pears in the area east of Cape Town in the late 1990s.

Fruit farming is notorious for heavy spraying regimes, he says. While it rids the fruit of pesky bugs it also kills off friendly bacteria. The more Mike sprayed, the more fertiliser he needed, locking him into a vicious cycle of rising inputs costs.

Eight years after deciding he was "tired of working for the chemical industry", Prevost is now in his fourth season of fully organic farming, producing 700 tons of apples and 100 tons of pears for the domestic and export markets.

Nourished by compost made of cow manure, bird droppings, mulched apple and other natural ingredients, the soil now boasts a richer moister texture, and, Prevost maintains, his fruit has "better legs" to withstand extreme weather.

The Western Cape is at the coal face of climate change in South Africa, with rising temperatures, increased drought and altered rainfall already making an appearance.

A market for their output

Fruit farmers complain of mildew on grapes from unseasonable rains and of unduly hot spells robbing apples of moisture.

Whatever the reasons for the shift, organic farmers are assured of a market for their output, with signs of South African, European and American importers all starting to vie for supply.

Tired of being thrown low-grade fruit by producers who send the cream of their crop overseas, Pick 'n Pay is backing a scheme to boost production and ensure a more varied supply.

Organic Freedom Project, a non-profit organising, recently announced plans to create 100,000 jobs in organic food and biofuel production in South Africa by 2014.

Europe's largest organic fruit and veg importer, Dutch company Eosta is also looking to secure its supply lines in South Africa against competition from American importers willing to pay almost double for a carton of oranges.

The Nature & More label - developed by Eosta before being spun off into a separate foundation - aims to bring consumers closer to growers in faraway countries.

A sticker on the product contains a code that customers can enter on a website to obtain a rating of the farm's environmental and social commitment.