The Chelsea Physic Garden — the other Chelsea flower show

This weekend I would normally be reviewing the Chelsea Flower Show. In this restricted year, it has been postponed to September 21-26, giving me more mornings free for my garden in May when it badly needs them. Instead of looking at temporary gardens along Main Avenue, I have been to look at a real Chelsea garden. It is far more rooted than those that are put together in a fortnight for the show’s spectators.

On Royal Hospital Road, just down from the show’s main entrance, the Chelsea Physic Garden has a history of nearly 350 years. Founded in 1673, it still occupies the four acres that were bestowed on it beside the river Thames.

It is London’s oldest botanical garden, a fascinating haven that has long outlived the comings and goings of trendy hot pants on nearby King’s Road. Its fine walls and greenhouses shelter plants that stretch and instruct me.

Near its centre stands Europe’s oldest rockery, constructed with basalt rocks provided in 1773 by Joseph Banks, that pioneer in the southern hemisphere. William Forsyth, of forsythia fame, and Philip Miller, author of a seminal gardening textbook for the early Georgians, are among the celebs with links to the garden’s flowerbeds.

Its historic pomegranate tree is still alive outdoors, despite this year’s frosts, which even killed bushes of rosemary in the gardens of country mice like me.

After an inauspicious start, the Chelsea garden has been having an exciting lockdown. Its director, Sue Medway, arrived in 2014 after years of managing properties, including Sissinghurst, for the National Trust.

By a bed of fading wallflowers, she explains that in 2019, the Chelsea garden, the staff and the educational mission cost £1m a year to run, a third of which came from weddings and events, a third from devoted friends of the garden and a third from visitors, up to 70,000 a year, paying the £9.50 entry fee.

The Physic Garden remains as excellent a venue as any in London for orderly parties, especially in summer. At a loss among other people’s guests, I have often spent happy evenings with the plantings, the alternative guests on show.

One of the garden’s distinctions is its range of greenhouses, designed by the famous company of Foster & Pearson in 1902. Inevitably their heating, teak timbers, cast-iron frames and interiors have aged, needing replacement.

For a cost of £1.75m, the basic work could be covered, with a further £1m for managing and developing the opportunity. Appeals for the main project were just about to be launched when Covid and shutdown intervened.

The timing seemed to have been sabotaged, but events turned out otherwise. A pledge of £500,000, to be matched before it was paid, led to a second successful appeal in November to the National Lottery Heritage Fund. Its contribution will total almost £900,000, activating the pledge from the charitable trust of Lord Browne, better known publicly for his years with BP. Supporting donors then brought the total to its primary target by the end of March this year.

Despite lockdown, work on the fernery, the tropical corridor and all the other collections is on schedule, the prelude to a rousing celebration for the garden’s 350th anniversary in 2023. It will be fascinating to see what the gardeners then make of the renewed space under glass.

Outdoors, several of them have been furloughed, keeping last year’s losses to £40,000, with further support from the garden’s friends. On the wall adjoining Swan Walk, head gardener Nell Jones showed me a huge unusual rose, the single-flowered Bengal Crimson.

For 20 years, Jones worked in marketing, taking up gardening only 11 years ago at the Physic Garden itself. Her previous life can have contained nothing lovelier than this important rose in the history of garden plants.

In the south of France it will scramble up and over its neighbours like a climber, making it a fine choice for winter-warm gardens. I have seen it thriving in Italian gardens near Turin where a superb specimen, neglected near a rubbish tip, persuaded me to try it in Oxford. Without a wall, it has survived all the frosts that 2018 and 2021 have thrown at it.

It is not hardy in open country, but my love of it has increased after seeing Chelsea’s fine specimen. In the Physic Garden it keeps company with tall blue-flowered echiums from Tenerife and plants from Madeira, the Canary Islands and so forth, pink-flowered melanoselinum to the fore. Like devoted Chelsea girls, these plants would rather die than settle in the chilly Cotswolds.

What is the point of a Physic Garden in the 2020s? Many plants lie behind the drugs that calm us and save our lives, but their extracts are now analysed, calibrated and mass produced by dealers and companies. Heart specialists no longer need beds of foxgloves for the digitalin they prescribe.

Physic gardens have lost their basic medical use but remain historic witnesses to the dependence of our life on plants. That legacy needs careful presentation. Bossy signs telling us that motor tyres are made from rubber plants — “did you know?” — bore visitors to distraction. Revitalised by donors, the Chelsea Physic Garden has a chance to integrate science and beauty in a subtle way.

A better route for it is to celebrate itself as a haven for rare, even endangered plants. Back in Madeira, the spread of international bedding plants has made Madeira’s own plants unfamiliar to visitors. A physic garden can also convey some of the classification and botany with which plants have been understood.

There is a satisfying beauty in well-run order beds, each showing members of a particular botanical genus, Ranunculaceae being one, the genus that includes all buttercups, not just those that are looking wonderful in nature’s disorder beyond the garden wall.

In an order bed I admired a lovely plant of the yellow-flowered Halimium lasianthum Sandling, a low and floriferous rock rose that loves a warm city. I also met the Chinese pea-flowered Caragana sinica for the first time.

The Chelsea garden still maintains 55 order beds, based on the traditional taxonomy of those botanical authorities, Bentham and Hooker. They combine and display plants in a way that purely flowery gardens never consider.

Even so, these order beds are becoming anachronistic. Genetic studies based on DNA have begun to reorder plant genera, lumping unexpected kin together. Should a physic garden be dug up and rearranged? I agree with its overseers that the Chelsea one should not. It can remain a witness to an older system, one with its own interest and beauty. Survivals are still precious in a modernising world.

In the 1970s, the garden was a seldom-visited oasis, open one day a week. Great gardeners advised on it and loved it, but its main external keyholders were the residents in Chelsea’s finest row of houses, nearby Swan Walk.

Now it is open six days a week, 11 months of the year. It has atmosphere, patches of beauty and at times an unfamiliar botanical cast. Go and enjoy it for a fifth of the price of a ticket to the Chelsea Flower Show. No prizewinning garden there will ever be able to offer as much.

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