The Keukenhof bulb and flower garden opens its doors to the public for the 70th time on Thursday and expects to attract one million visitors by the time it closes two months later.

This year’s theme is ‘flower power’ or connecting people across the globe with bright colours, hippies, peace & music, the organisation said at the formal opening ceremony on Tuesday.

Central to this year’s theme is the Flower Power mosaic which consists of some 50,000 bulbs planted in two layers and which is already flowering profusely, the organisers say.

The Keukenhof dates back to the 15th century when countess Jacoba van Beieren  gathered fruit and vegetables from the Keukenduin (kitchen dunes) for the kitchen of Teylingen Castle. Keukenhof Castle itself was built in 1641 and the estate grew to encompass an area of over 200 hectares.

Landscape architects Jan David Zocher and his son Louis Paul Zocher, who also designed Amsterdam’s Vondelpark, redesigned the castle gardens in 1857. That park, in the English landscape style, still constitutes the basis of Keukenhof.

In 1949 a group of 20 leading flower bulb growers and exporters came up with the plan to use the estate to exhibit spring-flowering bulbs, signalling the birth of Keukenhof as a spring park.

The park opened its gates to the public in 1950 and attracted 236,000 visitors in the first year alone.