The planter, which has a decorative covering surrounding a strengthened core, is the culmination of a development project launched by Plantscape in 2007 that saw the company take advice from the Centre for the Protection of National Infrastructure, a Government body advising organisations on how to protect themselves against attacks.

Successful tests were carried out gaining accreditation to the BSI PAS 68 standard after it withstood horizontal impact tests involving a 2.5-ton Toyota pick-up travelling at 40 mph.

Crucially, the planter was unmoved by the impact, but it did spill its content of compost and primulas. Though the planter sustained some damage, it fared better than the Toyota, which stopped dead, snapping its chassis and crushing its front end.