The RHS said that some exhibitors have grown five times as many plants to ensure they had plenty for the show, given the changeable weather.
The 15 show gardens, 21 small gardens and hundreds of exhibits at this year’s show include a £20 million diamond-filled garden and the Eden Project‘s Places of Change, a garden created by homeless people and prison inmates.
Paul Stone, designer and co-ordinator of Places of Change, said: ‘This feels like a step into the unknown. Of the 10,000 plants, one-third have been grown by amateur individuals who have been excluded from society.
‘At its heart is that horticulture is central to our lives and represents an opportunity for people to gain life skills and contribute.’
There will also be a new ‘Plant X Factor’ competition for plant breeders, giving innovators a chance to pitch their creation to a panel of judges.
More than 150,000 people are expected to visit the show over the next few days.
The Chelsea Flower Show opens to members of the RHS on May 25 and 26 and to the public from May 28 to May 30.
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