Garden owners should keep a better eye on their hydrangeas as the colourful plants are increasingly being targeted by thieves, the AD reported.

The paper suggests that some people believe hydrangea shoots can produce what has been described as ‘an intense high’ as well as pretty flowers.

While smoking hydrangea shoots is not forbidden by law, stealing them from people’s front garden is.

The Paulided family in Houten saw their hydrangeas disappear early on Saturday morning, plucked from the soil by a man on a motorbike who was caught on a neighbour’s surveillance cameras.

The man first passed the flowers, then went back and dug up two white hydrangeas. The theft took no more than a minute leaving the family to wonder ‘who would do this sort of thing?’

A brief search of regional media outlets reveals similar thefts in Badhoevedorp, Emmelord, Selwerd and Vinkhuizen this year, and others going back to 2005.

Grower Andries van der Woerd told the AD that only one of the many types of hydrangea seems to contain a hallucinatory substance.

‘You just have to know which one it is,’ he said. ‘But beware: it also contains hydrocyanic acid, which is a very toxic substance. So if you manage to get high, you’ll have severe pain in your stomach for at least three days as well.’