Usually the first Saturday in September. It brings the traffic to a standstill, but its worth having a look at the hundreds of flower-laden floats on their way from Aaslmeer, centre of the flower trade, to the city centre.

However, in 2007 the organisers announced the last Bloemencorso had been held because of the lack of sponsors.

The bulb growing area runs a flower parade from Noordwijk to Haarlem in late April.