Crisis at the Royal Horticultural Society

For two centuries it has put the haughty into horticulture, but the world's grandest gardening fraternity suddenly finds itself the centre of an unseemly controversy.

This week, the Royal Horticultural Society, which runs the Chelsea Flower Show, learned that its glamorous director general is to resign after just three years in post – the usual tenure is a decade or so – amid feverish talk of financial crisis, declining membership and redundancies. The society , which has long glided along as smoothly as a roller on a manicured lawn, is now in a state of shock. It conceded that the announcement was a "surprise." For that, read bombshell.

When Inga Grimsey, now 56, was appointed, she was the first woman and first non-expert to run the society. The half-Swedish skiing enthusiast, who once drove aid trucks to Romania, certainly stood out from tweedier colleagues. Previously, the sharp-suited Grimsey worked for Levi Strauss, the jeans company, and, more acceptably, for the National Trust. But while RHS stalwarts normally have the mud of their country gardens spattered over their Hunter wellingtons, she lives in London with her husband.

As Grimsey was declaring herself "ready for change" following her resignation, senior figures were wondering quietly if the RHS had ever been ready for her. In response to declining revenues, she has been driving through plans to prune 80 staff, nearly a tenth of the workforce, earning her the sobriquet of "the grim reaper".

Last year, income fell and membership dipped by 8,000. Now the RHS claims 363,000 members, a tenth of the National Trust's, which is celebrating record numbers despite the recession. English Heritage's membership has soared, too, to 687,000, with new members up by a third. In its defence, the RHS said yesterday that its membership is now "constant".

Behind some fairly petty point scoring over Grimsey's performance is an increasingly angry debate over what the RHS now stands for. Since 1995, it has been recognised internationally as the arbiter of plant classification. Yet one gardening writer suggests its attractions must now "compete with Alton Towers". Another says that "until a few years ago [the RHS] was very elitist and members became fellows, entitling them to put letters after their name. It then, successfully, turned into a mass organisation. But one has to ask what, other than a magazine, do members get from it?"

Grimsey has tried to sound "relevant", emphasising to the wider public the RHS's interest in allotments and tiny roof terraces as well as grander gardens. Since 2002 the Society has run the popular but unwieldy Britain in Bloom campaign. At this year's Flower Show, Grimsey awarded a gold medal – fashioned from Plasticine – to Top Gear's James May – for his Plasticine garden. It was the kind of populist gesture that grander institutions must now pretend to enjoy, and many members were uncomfortable with it. Others welcomed it, with one blogger noting that it demonstrated the "RHS has sense of humour, shock horror", and that Grimsey looked "rather foxy".

There is no question that this attempt to broaden the appeal of the RHS has irritated some trustees and staff. Even Grimsey's plan to promote family access at its flagship garden, Wisley in Surrey, was considered dangerously radical by some.

How removed this seems from the Society's high-minded inaugural meeting at Hatchards bookshop in London's Piccadilly in 1804. Then, John (son of Josiah) Wedgewood formed a group to present papers on horticultural discoveries. It was attended by just a handful of men, but included the heads of the gardens at Kew, Kensington Palace and St James's Palace as well as the president of the Royal Society and the lord of the admiralty. It gained its royal charter in 1861 after Prince Albert became a supporter.

One former senior executive believes that the Society has been in need of a shake up for some years but there has been resistance. Wisley staff have now been asked to work weekends so they can "interact" with visitors, a move that has caused "a big fuss", and there remains a tendency ''to stress the scientific, trials-based work and not talk to the common man. You will see a flower-bed with every type of hosta or salvia, with a little label giving an impenetrable Latin name but no help with plantsmanship. Unlike National Trust gardens, there isn't much romance.'' The source recalls a colleague's outrage when a toddler chased a duck at Wisley; such was the conservative culture Grimsey faced.

All of this reflects a contradiction at the RHS's heart. "It contains 'horticulture' in its title but 'gardening' in its mission statement," says the former executive. "Which is it? The tone veers from stuffy to over-eager to 'get down with the kids'."

Grimsey's arrival inspired mixed feelings. "The RHS makes the Lawn Tennis Association look modern," says a well known gardening figure. "It was the last Tufton Bufton organisation to change." But Tim Richardson, the gardening writer, says this lead newer and younger gardening enthusiasts to welcome the moderniser: "She was a breath of fresh air and quite glamorous. There were high hopes."

However, some were left disillusioned: "She turned out like John Birt at the BBC, over-managing," says one. "The trustees are very paternalistic, and some took a dim view of the redundancies. The society has been run by a cadre of plutocrats and old style bankers – Rothschilds, Schroders, etc – and there was a feeling this could have been better handled."

Another claims: "All she really did in three years was produce a plan to sack people. Staff have been anxious, going around saying 'why should we go? Our department is profitable'."

Her detractors have been busy spraying their poison. "She wasn't available like previous director generals and wasn't seen," I was told this week. "At Chelsea she would greet the Queen and make the obligatory speech, but that was about it."

One eminent horticulturalist hisses: "I don't know if she even has a garden at her London address. One never gained a feel for her." Her official biography is brief, though claims her childhood garden in Kent infused her with a love of gardening.

Grimsey's defenders – and there are many – point out that her tenure has coincided with the recession, reducing sponsorship and the exhibits at the Chelsea Flower Show. "City institutions did not want to be seen spending money on something considered elitist," says one respected RHS figure. "Ironic really as more people are gardening than ever, with massive interest in allotments."

Grimsey has been invited to stay until the cull of staff is complete in January. Meanwhile, the union has been warming to a spot of toff baiting. "The RHS are treating staff like compost," says Chris Kaufman, national secretary of Unite. "You wouldn't think a charity would operate like a Victorian mill owner." The RHS says that Unite represents "a tiny fraction" of staff and has "no mandate. There is full consultation and the union didn't even have the courtesy to send us its statement."

However, many members are perplexed that the Society should be having to dead head staff anyway. "It's always been well connected in the City," says one. "Past presidents like the late financier Peter Buckley had serious fortunes and attracted lucrative sponsorship. I was amazed the RHS was suddenly short of money."

Given gardening's burgeoning popularity, shouldn't membership have risen like the National Trust's? Unfair, say Grimsey's followers. "The National Trust has properties all over. The RHS has four properties [Wisley, Rosemoor in Devon, Hyde Hall in Essex and Harlow Carr in North Yorkshire] and nothing in the Celtic fringes. Plus Inga had to satisfy charitable and educational commitments."

The gardening world is notoriously closed and a fixer for Radio 4'sToday programme, who tried to follow the story up this week, howled "we can't get anyone to talk!" The RHS insists Grimsey's departure is amicable though admit that she has no job lined up. But perhaps in leaving, Grimsey has succeeded where some consider her to have failed in situ; she's made the Royal Horticultural Society suddenly rather interesting.