Keukenhof 2009 Theme: USA, New Amsterdam – New York, 400 years. Keukenhof is an unforgettable experience and the best place to get a taste of Spring!7 million bulbs are planted every year making it a glorious visual feast. In 2009 many of the activities will focus on the theme.  Opening dates for 2009: 19 March to 21 May 2009 daily from 8.00 untill to 7.30 pm (ticket office closes at 18.00).