From The Economist:
IF YOU live in Europe and are lucky enough to be given roses by your Valentine, there is a good chance that they were grown in Kenya—specifically, in one of the colossal greenhouses that blot out the once wild shores of Lake Naivasha, 90km (56 miles) north-west of Nairobi. Some 25% of Europe's cut flowers come from Kenya.
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Roses need labour-intensive watering, pruning and treating before they can be clipped and flown daily to buyers in Amsterdam and London. The best are sold through (Dutch) auctions to florists; the less good end up in European supermarkets. Kenya emerged as a flower power when Israel scaled down its own industry. It has since lost business to neighbouring Ethiopia, which offers tax breaks and better security, but Naivasha's perfect intensity of sunlight and days of near-constant length should keep it on top. In any case, the owners are stoical. “We're committed privateers,” says one. “We'll just pick up and move somewhere else in Africa.”
Not to ruin everyone's Valentine's Day, but there is sad side to this story:
In a country strangled by anger and fear, it is taking armed escorts and emergency airlifts to make sure that Kenya's most warmhearted export - the rose - arrives in time for Valentine's Day.
Kenyan flowers - mostly roses - account for a quarter of Europe's cut flower imports, and Kenyan growers have been pushing to keep exports up for the holiday despite ethnic violence that has paralyzed the East African country.
Finally, the "trade in everything" description does not apply everywhere:
The sale of red roses and red gifts has been banned by Saudi Arabia's religious police in the run-up to Valentine's Day, reports a local newspaper.
Officials from the Commission for the Promotion of Virtue and Prevention of Vice warned flower and gift shops to remove all red items, including roses and wrapping paper, from their shelves.
"They visited us last night," an unidentified florist told the Saudi Gazette. "They gave us warnings and this morning we packed up all the red items."
In Riyadh, the ban came into force on Sunday and will remain until after February 14.
The authorities believe celebrating Valentine's Day is un-Islamic and encourages relations out of wedlock, which are strictly forbidden.
The crackdown has pushed up the price of the flowers on the black market, with some florists making deliveries in the middle of the night, the paper said.
Couples defying the ban placed orders for red roses weeks before the deadline. Some were sending online Valentine's cards, and others were planning to celebrate the day in neighbouring countries, such as Bahrain, which has a more liberal approach to Islamic law