Gardening experts are teaming up with the NHS to promote the positive impact horticulture can have for people’s mental health.

The Royal Horticultural Society has already pledged its Feel Good Garden at this year’s Chelsea Flower Show will live on at a Camden and Islington Mental Health Trust site in London to help patients and staff there.

Now it has said RHS gardens from the next two years of the show will be given to NHS patients.

The announcement comes ahead of the opening of the Chelsea Flower Show, when celebrities and members of the royal family will get a preview of the gardens and displays at the central London site before it opens its doors to the public on Tuesday.

The world famous show will host a “gardening for health” forum, which will look at ways to promote non-medical treatments such as gardening or getting out into nature, for mental health, also known as “social prescribing”, alongside traditional measures.

And British rapper, singer and songwriter, Professor Green, who has regularly spoken about struggling with depression, will officially open the RHS Feel Good Garden which looks at how gardening can help with wellbeing and mental health.

Camden and Islington Mental Health Trust won a competition to receive the Feel Good Garden, which was launched to mark the value of gardening to mental health and wellbeing in the 70th anniversary year of the founding of the NHS.

Three-quarters of all NHS mental health trusts in England, 39 in total, entered the competition to win the garden, which has been created by award-winning designer Matt Keightley, and will be adapted for the Trust’s site.

Another two gardens from the Chelsea Flower Show will be relocated to NHS mental health trusts who win competitions in 2019 and 2020, the RHS has announced.

Sue Biggs, RHS director general, said: “With 75% of England’s mental health trusts entering this competition we have to make the most of the huge recognition at these trusts that gardens and gardening can make a positive difference to our health and wellbeing.

“We passionately believe that everyone should have access to gardens and getting our Chelsea Gardens living on is a core part of our Greening Grey Britain Campaign to transform grey spaces to green places for the nation’s heath, happiness and for the environment.

“We’re committed to continuing to work with the NHS for at least the next two years to share our gardening knowledge and help more patients and staff to grow.”

Professor Tim Kendall, NHS national director for mental health said: “The therapeutic value of spending time gardening and in green spaces is increasingly recognised, which is what has made this partnership with the Royal Horticultural Society so exciting.

“More and more, patients and their doctors are looking beyond medicines and traditional treatments, through a range of activities, including exercise, gardening and nature.

“We are absolutely thrilled that the RHS is pledging to work with us in future years, leading to the gift of a further two amazing gardens to NHS patients and staff.”