Botanists collected a record eight-and-a-half million seeds from a clutch of plants growing on a grass verge in Haywards Heath.

The tiny seeds were harvested in just one afternoon from the Common Spotted Orchid by staff working on Kew's Millennium Seed Bank Project, based at Wakehurst Place in Ardingly.

It is one of the highest hauls of wild flower seeds on record but represents just ten per cent of the seeds from the plants that were available.

Botanist Chris Wood, of the Millennium Seed Bank's research team, said: "There was a very healthy population of this wild flower growing on a grass verge outside a local hospital at Haywards Heath.

"Four botanists spent an afternoon collecting the seeds and we took less than ten per cent of what was available."

The scientists believe this to be the largest ever collection of wild flower seeds.

It is certainly the largest made by a Kew team since the botanic garden began seed collection in 1973.

The four members of the project's research department hunted down more than 200 individual plants and took a small number of the miniscule seeds from each Dactylorhiza fuchsii plant.

They were growing by the side of the A272 at Haywards Heath.

The local highways authority gave permission for the harvesting before their contractors mowed the area.

Weighing a mere three micro-grams each, the total collection fits into a tea mug.

In total 8.7 million or so seeds in the collection were taken from 216 spikes, or individual plants.

The seeds will be used for both safe storage within the Millennium Seed Bank's frozen vault and for collaborative research work with Kenyan and Australian partners.

Researchers at Kew want to undertake a global assessment of orchid seed longevity, leading to a realistic idea of how easy it will be to conserve them in places other than where they are naturally found.

The Common Spotted Orchid is a useful research tool as it's relative abundance makes it an ideal candidate for examining the seed storage behaviour of the Orchidaceae family.

The Millennium Seed Bank Project is an £80 million world-wide conservation effort supported by £30 million of Lottery funding from the Millennium Commission.