FloraHolland and the Aalsmeer flower auction together process around 13 billion flowers and plants annually and had sales of 3.7 billion euros ($4.68 billion) in 2005.
FloraHolland is the world's number one flower auction.
The two firms said on Thursday the Dutch sector was under pressure due to �international developments� threatening their global position. A spokeswoman said they currently �lack scale� and costs were �too high�.
They hope to cut costs through the merger, which is expected to be concluded before 2008.
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