Chelsea Flower Show 2016: from amateur gardener to director of the RHS - Sue Biggs is on a mission to turn Britain's grey cities green

Despite never having worked in horticulture or charity, Yorkshire-raised Sue Biggs became director-general of Britain’s leading garden charity, the Royal Horticultural Society, six years ago. She previously ran travel company Kuoni.

Today she is widely credited with radically changing the image of the RHS from fusty to forward-thinking. Since her appointment, membership has increased by 90,000 to 440,000 and almost 28,000 schools in the UK have signed up to her get growing campaign.

Down-to-earth and approachable, she believes gardening is the best therapy and is determined to see Britain become a greener place.

WHAT’S IN MY GARDEN

I’m an enthusiastic amateur gardener and a plantaholic, which is difficult, as my garden in Cobham, Surrey, where I moved four years ago, is small and was already bursting at the seams.

There are about 100 roses and as many lavenders, but my garden is also stuffed with clematis, tangerine geum, acid green euphorbia, violet iris, coral peonies, purple salvias and different types of grasses. I never learned the principle of editing down plants.

MY MOST TREASURED GARDEN POSSESSION

I bought a beautiful old Italian terracotta urn back from Umbria, where I used to have a house. It’s just over a metre high and there it sits in my garden, making me dream of life in Italy. I tried growing a brugmansia trumpet flower in it last year but that didn’t work so this year I’m just going to admire its shape and texture — or use it as a very large wine cooler.

BEST PLACE TO BUY PLANTS IN LONDON

Columbia Road Flower Market is just breathtaking. I’d also suggest Clifton Nurseries (near Warwick Avenue, in W9) or one of the farmers’ markets that the RHS is supporting. There is one at Columbia Road in E2 on June 19, then Lambeth Country Fair, July 16-17, and Marylebone Farmers’ Market on September 11.

There’s always a great selection at nurseries just outside London. And with 12,000 plants to choose from at Wisley Plant Centre, in Woking, Surrey, which is a short stroll from my office, it’s no surprise I buy nearly all my garden plants there.

If it’s cut flowers I’m after, I stop off on the way home at Nikki Tibbles’s Wild At Heart in Pimlico (Pimlico Road, SW1). The artistry and range of flowers in its displays is beautiful.

GARDEN MERCHANDISE

In town, I’d highly recommend Petersham Nurseries in Richmond. They’re fabulous for stylish and unusual indoor and outdoor gifts as well as practical garden gear. I bought some great lace-up rubber wellies there, by Ilse Jacobsen.

There are also some bright new ideas from the 12 finalists of this year’s RHS Chelsea garden product of the year, including a mobile app, hub and tap unit so you can remotely set, pause and adjust watering schedules as well as be updated about weather changes, from Hozelock; a concrete fire pit that doubles as a table from Solus Decor, and an outdoor bench with back and arms that appear to float from Sitting Spiritually.

THE CHELSEA PLANTS I’LL TAKE HOME

This year’s RHS Chelsea Flower Show features lots of fresh green ferns in many of the show gardens. They look fabulous, so I’m definitely going to squeeze some of those in my own garden. Raymond Evison is one of my favourite nurseries and I will be ordering the pretty pink and mauve Clematis Volunteer, which celebrates the enormous work undertaken around the world by volunteers.

And I must have the gorgeous Mary Berry rose from Harkness Roses, which was named in honour of our RHS Ambassador. It’s the colour of clotted cream and smells sensational.

MOST COVETED GARDEN OBJECT

If I had a large garden, I’d steal out at midnight to give one of Heather Jansch’s life-size bronze driftwood horse sculptures a new home.

MOST INSPIRING LONDON PUBLIC SPACE

The stunningly beautiful and environmentally important meadow planting around the Olympic Park, above, created by James Hitchmough, Nigel Dunnett and Sarah Price, made us all realise that civic planting could be colourful, and wild, and exquisite. Indeed, it was so spectacular that photographs of it raced around the world, reminding everyone what a nation of gardeners we are in the UK.

MY FAVOURITE LONDON LANDMARK

I adore the view from Waterloo Bridge, with the Houses of Parliament in one direction and St Paul’s in the other, and Somerset House straight ahead, all threaded together by the beautiful River Thames. That’s a view I’ll never tire of.

BEST OUTDOOR CAFE

Inn the Park is a real hidden-away treasure, an oasis overlooking the ponds, wildlife and stunning gardens of St James’s Park. The outdoor terrace is wonderful for an early breakfast or a post-work glass of something cold and bubbly. It’s impossible to believe you’re in the heart of London.

MY LATEST PROJECTS

With our current £160 million investment we have many projects, from creating a new fifth RHS garden in Salford and investing in RHS Garden Wisley in Surrey, to supporting even more communities at grass-roots level across the UK.

Greening Grey Britain is our most recent campaign, and is hugely important, especially in major cities. We’re losing our green spaces at a terrifying rate — hard surfaces in London gardens alone increase by two-and-a-half times the area of Hyde Park every year — which leads to environmental problems such as destroying vital wildlife habitats and leaving us vulnerable to flooding.

The RHS Greening Grey Britain Garden for Health, Happiness and Horticulture at Chelsea Flower Show this year is championing the benefits of plants and through our partnership with the Evening Standard, we will be able to relocate the garden to Angell Town, Brixton, which we hope will bring joy to the residents for years to come.

We’re also holding a Front Garden Summit as part of Chelsea Flower Show week where we will discuss the problem of losing green to grey with planners, developers, councils and policy makers, so I hope this leads to more solutions.