The coalition Government has picked up the peat elimination baton where the outgoing administration left it - garden centres have until 2020 to stop selling peat-based growing media, while growers have until 2030 to forgo peat in plant growing media.
The line of reasoning appears to be that as the industry has achieved some degree of peat substitution over the past decade on its own initiative, one more decade ought to see it through to a complete replacement.
However, this is not a view that finds favour with NFU horticulture adviser Chris Hartfield. "Growers and growing media companies have invested around £43m to get to where we are now, which is a 57 per cent peat-free industry," he says. "But every percentage gain from now on will cost more, so it becomes more challenging - and the Government is not about to dip its own hand in its pocket. Yet we're talking about hundreds of millions of pounds."
Costs of switching will fall harder on some growers than others, he adds. "Some companies are designed entirely around peat - it's what their potting machinery is designed to handle. The last thing those growers will want to do right now is invest in new machinery."
As things stand, he says, the only place those costs can come from is the consumer, in the price they pay for plants and growing media. "Right now that's the bottleneck," he adds. "Retailers won't put up prices."
To win customers round, Defra has said it will aim to raise the public profile of the issue. "But no one has managed that in the past 20 years," claims Hartfield. "Most gardeners are still quite ignorant of the issue, and the same goes for edible horticulture.
"They won't pay more. That needs to be tackled, otherwise you are 'choice editing' - replacing one product with another at a higher price. Even that would require all retailers to agree and to act as a group, yet they are very competitive."
The industry-led approach could also result in peat-based products still being imported, putting UK growers at a big disadvantage, says Hartfield. "The solution shouldn't put us in an uncompetitive position. The current Defra ministers are quite a green lot - there's a 'we want to save the world' outlook, but they only see the answer in UK terms."
Tough nuts to crack in terms of replacement media include young plants and pot herbs, he adds. "Growers have spent decades looking for alternative media without finding one that is cost-effective."
Even when the technical challenges of growing in peat-free media have been overcome, the challenge of upping the scale of production has not been fully addressed, according to William Sinclair Horticulture managing director John Tugman.
"To replace peat, we will need 4.6 million cubic metres of alternative media a year," he says. "The lead time for that will be several years. But no sensible business will commit to that while peat is still available."
The company has invested three years and £1.5m in developing Super Fyba, a growing medium derived from woody green waste, which it launched to UK growers last year. This could easily fill the hole left by the withdrawal of peat, Tugman suggests.
"It's constantly being renewed, turns a liability into a resource and can be made locally. It will be marginally more expensive than peat, but significantly cheaper than the alternatives such as coir. However, we need the confidence to up the scale of production and we believe legislation will be required to drive the process."
Such a move would stimulate other suppliers too, but he is sanguine about this. "There will be competitors - one is already rubbishing Super Fyba. I'm sure they are looking at the process, though it will take them a few years."
While the idea of writing peat-free into law sounds drastic, Tugman believes it would provide an opportunity for UK growers as well as media suppliers. "We need a level playing field for UK industry - not different rules for importers," he says. "It will be an anomaly if you can still buy imported peat-grown plants." Indeed, a market restricted by law to peat-free plants would put those UK growers who had made the switch at a huge advantage, he points out.
It would also keep growing media production local, rather than outsourcing peat supply overseas. "There has been a reduction in commercial peat use from 70 per cent to 46 per cent over the past 10 years, but the total volume used has gone up from 4.7 million to 6.6 million cubic metres," he says. "We have also been importing more, which has cost around 100 jobs in the UK."
This may seem ironic coming from a company "founded on peat", he adds. "Peat is cheap, lightweight, stable, growers are familiar with it and horticultural equipment is designed with it in mind. But I am a realist. Change can happen sooner than you think and we need to be ready for it - not have it imposed to our detriment. Look at how quickly digital replaced film-based photography and where it left film suppliers."
But Hartfield does not favour the legislative approach. "An eventual ban would be not so much carrot-and-stick as a double stick. It would mean switching or going out of business," he says. "But I think it's pretty much accepted that you can't just outlaw it - you get into all sorts of issues."
Hayloft Plants owner Derek Jarman agrees. "John Tugman clearly has his own interest," he says. "But it's a daft idea and quite impossible for competition reasons, and I don't think the garden centres would stick it."
Indeed, a Defra representative appears to scotch the idea, saying: "The UK has very limited legal grounds for unilaterally banning the peat imports from other EU countries and restricting the free movement of goods within the European community."
Responding to the charge that peat withdrawal will disadvantage UK growers relative to importers, she says the voluntary approach should extend to them too. "We would like to see retailers treating imported growing media and plants in the same way they treat domestic growing media and plants and ensuring that they do not sell peat-containing products after the phase-out dates, regardless of their source."
Not that the impetus to move away from peat is unique to the UK, she adds. "In high-level European and international fora, peat is increasingly the focus of discussions and it's likely that there will be ever-growing pressure to reduce greenhouse gas emissions from peat extraction, to preserve internationally valuable biodiversity in lowland peat habitats and to reduce waste to landfill by switching to waste-derived products."
HTA director of business development Tim Briercliffe points out that one "stick" that Defra has already indicated it may use would be a tax on peat, rather than an outright ban. This would be among the options if the proposed review of the process in 2015 found that voluntary measures were proceeding too slowly - although it would be a "last resort", he adds.
Briercliffe says he has pressed natural environment minister Richard Benyon on how British growers are not to be put at a disadvantage by forswearing peat. "He has committed to addressing it at EU level," he says. "However, the issue hasn't excited Europe and there certainly won't be any measures in place there within the timescale we are working to here in the UK."
- Derek Jarman, owner, Hayloft Plants
"We are moving with the industry. We use peat-reduced mixes of around 40 per cent and don't see much difference for most crops. The problem is with propagation. Without peat the results aren't as good - the other media just aren't reliable enough. And then there's the extra cost, which you have to pass onto the consumer. It's the consumer who dictates what we all do and what they mostly want is attractive, good-value plants."
- Charles Carr, director, Lowaters Nursery
"I don't know how many growers would have the confidence to go 100 per cent peat-free. We are currently holding peat-free trials with Vital Earth - we'll know in a few months whether that's something we'll continue with. I would certainly consider it if it was both cost-effective and maintained the quality of the plants."
- Dougal Philip, owner, New Hopetoun Gardens
"Whatever you think about the peat argument, peat has lost and now we have to deal with the consequences of that. Having said that, it's not coming from the consumer. We had a huge promotion at New Hopetoun Gardens, but customers just weren't interested - we couldn't get them to engage in the debate."