Colombia keeps cocaine from spoiling Valentine's Day flowers
A worker carries a few dozen rose buds harvested at the Ayura flower company in Tocancipa, north of Bogota, Colombia. (Fernando Vergara / Associated Press)
Cocaine is probably the last thing most people think about when buying roses.
But every year, police and growers in Colombia must work around the clock to make sure that the romance of Valentine's Day isn't spoiled by the drug, the nation's other major export along with...