The Royal Botanic Garden Edinburgh (RBGE) believes its new John Hope Gateway, which opened this week, will rank as a facility worthy of the garden itself.
According to head of visitor services Alan Bennell: "We always aspired to have a proper welcome. With our four remarkable properties (Edinburgh, Dawyck, Logan and Benmore) we can claim to be one of the world's top five botanic gardens, but our visitor facilities have been second-rate."
Already the new visitor centre at RBGE's Dawyck garden in the Scottish Borders has become a "five-star attraction" since opening last year, he says.
And a budget of £15.7m has allowed the Edinburgh garden to go some way beyond what Bennell calls the "wooden hut syndrome". With £10m from the Scottish Government, around £2m from the Heritage Lottery Fund (HLF) and further contributions from other philanthropic bodies and individuals, the building is "on budget and only a little late in the season", says Bennell, adding: "The team has been working 60- to 80-hour weeks putting this together, because they are excited about it."
Designed by Roddy Langmuir of London-based Edward Cullinan Architects, the Gateway gives views out to the gardens in all directions. Even before visitors enter, they can see through the interior landscaping up a Caithness-stone-lined ramp on the far side leading to the garden beyond.
But once in the vestibule, the first feature that visitors encounter is the toilets. "An important feature - people complained about the old ones being substandard," says Bennell.
Passing into the main display area, visitors will be personally greeted by garden rangers. On the ground floor there is space for both temporary and permanent exhibitions, incorporating a range of media, as well as what Bennell describes as a "quality retail facility".
Beyond that lies a "real-life science studio" for events that will further public engagement with science and scientists. "It won't just be for the botanics, but also for the Scottish Wildlife Trust, the RSPB, (animal research establishment) Moredun and the McAulay Institute," says Bennell.
"We already have fantastic engagement with the public, and others can use this platform. There's even the potential for live links with our field stations in China and Belize."
The building's interior is scattered with motifs from the plant world, such as a plant cell cross-section that masks the light fittings and triangular porthole windows inspired by unicellular diatoms.
Even the dramatic spiral staircase calls to mind the double helix of DNA. This leads visitors up to a table-service restaurant that will provide breakfast, lunch and tea — even opening earlier at the weekend for the former, and complementing the Terrace Cafe elsewhere in the garden, which will remain. And by staying open until 6pm even in winter, the building will have a different - though no less striking — appearance in the dark.
The first floor will also accommodate corporate events and has already housed a wedding. "The guests were gobsmacked," says Bennell. "And you learn so much. There will be teething problems, but we could have snagged until Christmas - it's better to just get on and use it."
On the same floor are a community education room, vital to securing HLF funding, along with team offices and a meeting room, while at the other end a broad wooden staircase leads out into the biodiversity garden and doubles as a mini-auditorium for possible outdoor performances.
The building's ceiling is supported by innovative Glulam-engineered timber beams, while the roof features large windows for internal lighting, Sedum matting, solar panels and even a helix-shaped wind turbine - though staff joke that it serves only to power the computer which monitors it. Even the toilets incorporate "brown water" recycling.
Heating in the building will be provided by a biomass boiler, fuelled by wood from the Duke of Buccleuch's estate. "It's as economic as possible to run," says Bennell.
The Gross Max-designed perimeter landscape, including biodiversity garden, will take a further six to nine months to complete — after which a formal, possibly royal, opening will be held next spring.
By then, it is hoped the building will already have established itself. Two-thirds of the garden's 600,000 annual visitors previously entered by the East Gate and some "re-education" may be required to encourage them to use it again after two years of closure, Bennell explains.
The lack of a direct city bus link to the gate remains a niggle, he adds, as do weekday parking charges on the streets outside.
A shuttle service in the garden "is still an ambition" for Bennell, as are improvements to facilities at the garden's East Gate. He also insists the Edinburgh garden will remain free to visit.
"People have tended only to visit the garden when the weather's nice," he adds. "With this, it becomes more of an all-weather attraction and, what's more, it will make people want to come back and news will spread by word-of-mouth."
Together, the four gardens - Edinburgh, Benmore, Dawyck and Logan — attract around 750,000 visitors a year. Bennell is clear about his aim: "I want to crack a million before I retire."
RBGE's other updated visitor attraction is the Fernery at Benmore.
"We have wanted to restore Benmore's Fernery for 40 years," says Alan Bennell. "Until now it had simply deteriorated on our watch. Now we have paid our debt to the garden's heritage."
The Argyll garden is famous for its big trees, planted by its founder James Duncan in the late 19th century. But Duncan was also responsible for the equally impressive Fernery, which tapped into the Victorian craze for ferns before falling into disuse in the early 20th century.
On a promontory in a far corner of the garden, the Fernery was a listed building, though no plans or photographs of the original layout or roof remain. This freed designers' hands, says garden supervisor Neil McCheyne.
"It's a modern interpretation — Historic Scotland didn't ask for a complete historical reconstruction, which would have given us a headache to maintain. But the gables ends show what the original profile of the roof would have been."
The building's listed status helped secure HLF funding for its restoration. "It hung in the balance until we got that," says McCheyne.
This was confirmed in November 2007 and accounted for 40 per cent of total costs. "Generous local donors" also helped — but unlike the Gateway, no major government funding was involved.
With the funding in the bag, work on-site proceeded briskly, beginning in May 2008 and finishing a year later. But its high, prominent site made for awkward access, necessitating a crane and scaffold and much manual handling.
The original public approach, up a winding path through a gully, has been reinstated, with hardy ferns — including some rare UK natives — in terraces on either side.
The Fernery itself houses more than 70 species, including a high proportion from wild origin.
"There is a degree of plant conservation and also of raising public awareness of the issues," says McCheyne.
"Ferns generally like moisture and free drainage, as well as high light levels, though some are also deep shade dwellers," says McCheyne. RBGE fern expert Andy Ensoll "has given us a really good steer on what should go where", he adds.
One of the most striking features of the house, in contrast to other recent high-profile glasshouse openings, is its simplicity: no climate-control computers, no heating, manually controlled vents and a regime of watering plants entirely by hand.
"Andy was against misting units, as he didn't want moisture sitting on the crowns," says McCheyne. Hand-watering means that, for example, tree ferns can have water applied to their stems.
It will end up with a mixed canopy, with plants of intermediate height and an understorey under the dappled shade produced.
McCheyne adds: "We don't want it to become a complete jungle, so there will be some thinning out."