The British and Kenyan governments weighed into the growing debate over "food miles" yesterday, insisting it was ethically and environmentally sound to buy flowers from Kenya on Valentine's Day.
There is increasing concern at the amount of carbon emitted by the fleets of aircraft that carry millions of flowers to Europe every day from the impoverished east African nation. People in Britain will buy 10,000 tonnes of roses today.
Joseph Muchemi, the Kenyan high commissioner to Britain, said: "'Food miles' is a valuable concept but it must be looked at in the whole. It is neither fair nor sustainable to stigmatise certain goods purely on the basis that they have been freighted by air. 'Food miles', or the distance food has travelled, is on its own not a reliable indicator of the environmental impact of food transport."
Hilary Benn, the international development secretary, said that while people wanted to buy ethically and do their bit for climate change, they often did not realise that they could support developing countries and reduce carbon emissions.
"Recent research shows that flowers flown from Africa can use less energy overall than those produced in Europe because they're not grown in heated greenhouses.
"So, this Valentine's day, you can be a romantic, reduce your environmental impact and help make poverty history. This is about social justice and making it easier, not harder, for African people to make a decent living."
Mr Muchemi said Kenya provided 31% of Europe's cut flowers, directly employing 500,000 people and another million through auxiliary services.
Air-freighted fresh flowers, fruit and vegetables from the whole of sub-Saharan Africa accounted for less than 0.1% of total UK carbon emissions, he said. Moreover, while the average Briton emits 9.3 tonnes of carbon a year, the average Kenyan is responsible for 0.2 tonnes.
"European nations must look to reduce their emissions first before penalising African producers. A boycott of Kenyan roses or green beans would be disastrous for many Kenyan farmers, especially smallholders, and would do little to mitigate climate change."
Mr Benn pointed to a recent study that showed emissions produced by growing flowers in Kenya, where it is warm and sunny, and flying them to the UK can be less than a fifth of those for flowers grown in heated and lighted greenhouses in the Netherlands, Europe's main producer of flowers. "Climate change is hugely important to the future of developed and developing countries but if we boycott goods flown from Africa we deny the poor the chance to grow; their chance to educate their children and stay healthy.
"We in the west can have more impact on our huge carbon footprint by turning off our TVs at night and using energy-saving lightbulbs."
Mr Muchemi said he was concerned that plans by European retailers to introduce labels on their products more clearly identifying their origin could hit Kenyan farmers. "We can't have a situation in which poor farmers in Africa pay the price for European carbon emissions. It's simply not fair to penalise African farmers."
Environmentalists, though, are concerned about the ecological impact that flower growing is having in Kenya.
As we report in Society Guardian today, the thousands of workers who have flocked to the shores of Lake Naivasha to work in the flower-growing areas are placing enormous strain on the local ecology, such that the lake could soon be polluted beyond use and have all but dried up in the next 10 to 15 years.
David Harper, a University of Leicester ecologist, says the flower trade is devastating the area. "The lake is being destroyed at an alarming rate by the sheer pressure of people on it." He does not advocate boycotting Kenyan flowers but wants to see a "Fair Trade" system and "Fair Planet" label to highlight the problem. Its profits would be used to improve the lake's environment, he says.
The idea of food miles is an extension of the argument that the further things are transported to Britain from other countries, the higher will be the amount of carbon dioxide emitted.
The study mentioned by Hilary Benn yesterday, though, shows that the arguments can become complex if, in the case of fresh flowers, they are also produced in Europe but in heated greenhouses, which emit CO2 in far greater quantities than aircraft that bring flowers from Kenya.