Free onions at the Onion Festival. 30 March - 1 April 2011 30 March - 1 April 2012. The Netherlands has a large surplus of onions. To prevent them from rotting or being thrown away, Mediamatic saves a quarter of a million onions from Texel farmer Jo Flens. In the weekend from 30 March to 1 April you could pick up unlimited free onions at the VOC quay at the Onion Festival.