Forget the credit crunch, says Tom Tree, mulling over what makes tree trends. The media is more influential than cash crises and, furthermore, the weather, reckons the wholesale manager at Pantiles, hitting the play button for Gardeners' World.
And while the sliding economy is a trend without a friend, the new face at the BBC, Toby Buckland, can help spawn a multitude of fads and fashions. When these people say tree X is in, "it can make or break businesses", says Tree.
So it's just as well for Tree and his ilk that Buckland and Alan Titchmarsh seem to like their trees big. Pantiles is a big-tree specialist and business, he says, is good.
"Buckland and Titchmarsh carry clout, as do the flower shows. Recent trend-setters like silver birch have been overtaken by less common trees with the helping hand of the media," he says of examples like the red-leaved Judas tree, Cercis canadensis.
Old favourites like lime and oak will always remain popular, says Tree. But this more fleeting age of television, glossy magazines and show gardens has caused a cultural jolt or two. Trends are defined not so much by the traditional stalwarts like oak.
It's the "flash in the pan" making more noise and lots of the running. Recent leaders include Acacia. People value hardiness and screening qualities enough to pay a hefty price of £200 per tree, he says.
"Trends are also contradictory. People like slow-growing hardiness, but the warmer climate is coaxing them to chance something more tender. Scotland still has limits, but less severe frost pockets in areas like Surrey can enjoy exotic touches like olive."
And the credit crunch, far from triggering dour conservatism and frenzied cost cutting, is prompting more considered, less knee-jerk buying trends. The credit crunch, he insists with gasp-inducing bullishness, "is all about mental attitude".
Sales and marketing director Frank Sandford of Wolverhampton-based Boningale Nurseries says tree shortages and past gluts of once-popular trees could have a big impact on today's trends and those of the future.
"Fastigiated trees like Carpinus betulus Award of Garden Merit (AGM) and oak have enjoyed high demand over the past few seasons. But they are now in very short supply and prices are going through the roof. Limes are also in shorter supply, but for other reasons.
"For a time they were all over the place and you could buy any size and variety you wanted. The market was so saturated that suppliers were having to burn stocks in their fields. People cut back, demand grew, and now they are becoming a little scarce."
Trends, always tough to forecast, are now virtually impossible to predict as the UK market becomes ever-more entangled with markets in Continental Europe. When Russia swallows up "huge chunks of stock", we feel the shortages, he says.
"Prices went up last season and a dearth of certain varieties and sizes was felt severely over here. UK production of trees has been in decline for 10 years and with firms like Notcutts quitting tree production, we are more reliant on imports."
So trends are being dictated as much by overseas production and demand as the wants of UK clients. Some types of tree, however, retain their popularity and the trend for specifying bigger trees looks like continuing for some years to come, Sandford feels.
"They are often the key structure plants to a landscape design and if you want an avenue it's hard to achieve the same effect with smaller trees. It's also tricky downsizing trees in inner cities without increasing the risk of vandalism."
Wyevale Nurseries sales director Doug Reade is more concerned about vandals of another kind, and this is where UK trees have the edge over European stock. Southern Europe, he says, has sent over unwelcome migrants of late, which could shake up trends.
Processionary oak moth and the London-plane-attacking canker originate from southern Europe and are causing a huge "kerfuffle", he says. Trees native to Britain, on the other hand, are free from such pests and are therefore likely to be more popular.
"This will play in our favour, as our trees are clean: a disease elsewhere can therefore help our industry. The euro also throws up rays of light on a stormy horizon. Dutch and German trees are suddenly much more expensive, making ours more attractive."
And trees that are proving most attractive to Wyevale customers at the moment are the natives: birch, alder, oak and hornbeam. Though Reade's firm is a big supplier to housing and commercial sectors currently in crisis, orders have remained steady.
Projects like Cabot Circus at Broadmead Shopping Centre, Bristol, are good for the order books at Wyevale (see case study, top). The scheme took 10 years to plan, three to build and included 140 trend-setting trees near homes and shops including Harvey Nichols.
Not everyone is as upbeat about the euro as Reade. Marketing and sales manager Nick Coslett of Palmstead Nurseries in Ashford, Kent, says the rising cost of imports, dwindling UK grower numbers and a dependency on European trees are big drawbacks. He says the need for frugal modesty could forge trend-setters out of native plants and seedlings, which are cheaper than "worked trees". While landscape architects aren't always conservative specifiers, a weak "design link to a project" can make them so.
"Creative minds are often divorced from the commercial side of projects, while tighter finances could lead to watered-down tree schemes or a big squeeze on landscape contractors from main contractors. These factors are likely to affect trends."
But nursery manager Denise Westmarland of Sempervirens in Twickenham says the economic slide will not wipe out the market for trees in housing. There will always be demand for homes, insists a woman who enjoys good sales of Acacia and birch.
The credit crunch will make smaller trees more popular and the instant garden less so, she reckons. Hillier Nurseries has a different view and is maxing out on a service for the biggest trees in the market; the "super-semi-mature" monsters of 1m girths.
These oaks and London planes cost around £6,000 each and form arboricultural anchors to commercial schemes (HW, 4 September). Super-semis have been growing for 20 years on the firm's Hampshire site and are now ready.
"Customers used to look abroad to buy really big trees and we thought it was time someone grew them here," says director Hossein Arshadi, who echoes Reade's mantra about the dangers of pests and disease from stock grown overseas.
"The old favourites like lime and London plane are still in trend, but customers are tending to go for more native-type material. So where Betula utilis var. jacquemontii used to be a hot favourite, there's been a move towards Betula pendula AGM."
Sales director Keith Sacre of Barcham Trees in Ely, Cambridgeshire, rates Hillier's lofty ambitions for its super-semis initiative.
"Hillier has done a bloody good job in its efforts to produce big trees and deserves the rewards," he says. "But there seems to be a historic preconception that the big German nurseries are always associated with developing large trees."
Sacre is delighted at the wilting demand for the spindly so-called lollipop trees favoured by developers. He gives a warm welcome back to "good old favourites" like birch, lime, cherry and Sorbus.
Company secretary Susan Anton of Deepdale Trees in Sandy, Bedfordshire, agrees that the old favourites are the new favourites again. Tightly formal gardens with clipped trees are not as hot these days as the more native and naturalistic alternative.
Beech, field maple, crab apple, lime and Amelanchier are selling well and this growing trend for the naturalistic feel is being spurred by people's burgeoning interest in wildlife and the environment, she says.
"Our thoughts are going back to feeding bugs and bees, and tackling other wildlife issues. The old favourites are also being used for traditional design elements like tree avenues, so bigger-girth limes along with hedging are doing pretty well."
And the trend-setting trees that fulfil this environmental agenda across business parks, housing developments and private gardens are being dictated by another, unmissable factor, says Anton.
The growing prominence of the gardening media and flower shows, she insists, is helping designers, specifiers and growers capture the still moment in a fast-flowing, media-obsessed world to make a "lasting mark" with trees.
CASE STUDY: CABOT CIRCUS, BRISTOL
Landscape architect: Novell Tullett
Tree supplier: Wyevale Nurseries
Architect: Chapman Taylor Architects
Client: Bristol Alliance Consortium - Hammerson and Land Securities
Cabot Circus - a new £500m mixed-use, retail-led quarter that opened last month - offers a super-sized snapshot of trends in urban tree planting, says the team that blended them into the 15ha site in Bristol.
Landscape architect Novell Tullett and Wyevale Nurseries used 140 trees around a tight knot of new streets, open squares and a home zone. Oaks defined a piazza and punctuated Welsh pennant paving, granite details and red sandstone.
But plane trees form the backbone, have historic associations with Bristol streets and form part of the visual "vocabulary" of the area, says director Jane Fowles of local landscape architecture practice Novell Tullett.
"We had a huge job convincing traffic engineers that 3m-high trees would lift canopies above sight lines to traffic lights," she says. "It also took time to reassure shop-letting agents that trees would not block out views to the shop windows."
Like the traffic lights, Novell Tullett used big trees, in this case Fraxinus excelsior 'Westhof's Glorie' AGM, to avoid competing with frontages. Hammerson managing director of UK development Jon Emery rates it "one of the best shopping streets in Europe".
Four 6m-tall Quercus robur f. fastigiata imported from Italy form a design highlight. Framing the entrance to a friary, they rise above sandstone paving made of 800sq m blocks. These give an appropriate "gravitas" to a key architectural element, she says.
Other stock sourced from Wyevale, which grew the trees for two years before trucking them to Cabot Circus, included flowering crab apple for residential streets, Quercus palustris AGM and Fraxinus angustifolia 'Raywood' AGM.
Two favourites of Fowles' were an existing Acer saccharinum, which was kept for the scheme and is big and "blowsy with a silverish texture when blowing in the wind". A 250-year-old 20m plane tree with a 20m crown has strong historic resonance. She was also pleased to source pennant stone from a family firm in Cardiff.
"We used Fraxinus, Quercus and plane - proper forest trees - not the ludicrous lollipop types so often used in commercial developments. We wanted them to contribute to the street scheme and that's what they are doing."
- Big traditional trees like oak and London plane are in, with a few unusual touches such as the red-leaved Judas tree, Cercis canadensis.
- Faddish trees are stealing more limelight, with Acacia and evergreen oak forging strong status.
- Warmer weather is prompting more experiments with exotics like olive in less-severe frost pockets outside of London, such as Surrey.
- South European tree diseases like bleeding canker may prompt people to shun imported trees and plump for pest- and disease-free varieties native to Britain.
- The credit crunch is fuelling a trend for smaller trees and more permanence than the instant garden, with compact favourites including birch and Acacia.
- Growing awareness of the environment is pushing native and naturalistic themes up the agenda, good for beech, field maple, crab apple and lime.