The use of peat in horticulture continues to be scrutinised in the prolonged run-up to the medium’s eventual withdrawal from the UK market. But suppliers of alternative growing media are confident that the gap can be filled with products that are at least as good.
A recent update published by the Horticultural Development Company showed a seven per cent overall decline in growing-media sales to the professional grower market. This accounts for around 30 per cent of the total growing media market, consuming around 1.2 million cubic metres a year — slightly more than the volume of Wembley Stadium.
The figures reveal that while peat’s share of the professional market dropped from 72 per cent in 2011 to 69 per cent in 2012, the share of peat-free media also declined. With the exception of Northern Ireland, all areas of the British Isles and continental Europe saw their sales to the horticulture sector decrease over the period.
But this may simply be a transitory effect of last year’s poor weather. Bord na Móna has already hailed its peat production this year as being two-thirds higher than its target figure, and four times higher than 2012’s wash-out season. Head of peat operations Paul Riordan says: "After last year’s poor harvest we needed an exceptional harvest and we are delighted now to have exceeded expectations so spectacularly. The good weather played its part in getting us here along with a new operations plan devised last winter and implemented in summer."
Coir suppliers are generally in buoyant mood. According to Botanicoir managing director Kalum Balasuriya: "More and more people are choosing coir as a substrate — they like the fact that it’s renewable and disposable, and that the price has come down. We have several new or refined products this year, each with different water-holding porosity, depending on the requirements of the crop.
"Cucumbers, for example, prefer it wetter, while sweet peppers prefer a drier growing medium. In both cases you still want it to hold water and nutrients, while draining freely." The company’s new netted grow cubes for propagators "have been successful in trials and are solid enough to be machine-handled", he points out.
The coir market is seeing some consolidation as growers come to regard quality and consistency as imperative, says Cocogreen sales and marketing manager Thomas Ogden. "We have seen increasing demand even while overall demand is down, as customers switch either from peat or from other coir suppliers," he adds. "It’s a maturing market, with a dwindling number of suppliers. Some peat suppliers have tried to supply coir, in either pure or blended form, but even the reputable ones haven’t been able to offer the quality or consistency."
Being vertically integrated back to production in Sri Lanka allows Cocogreen to overcome such problems, he says. "That and a qualified technical team to conduct trials and formulate the mixes. The gap is getting wider between suppliers that have control over their product and those that don’t — that’s going on everywhere. You need the whole package to provide the quality and affordability."
Ogden explains that the same applies in other countries, in line with the growing global demand for coir. "Here the medium-to-large soft-fruit growers are all behind coir," he says.
"Smaller growers are more likely to still be using peat, as Irish and Dutch suppliers still have good distribution in that market, but they are likely to follow the larger growers into coir. We have even had some success with growers north of the border, who have long been loyal to peat."
Horticultural Coir managing director Tom de Vesci adds stability and durability to the virtues of coir. "Your crop is likely to be in the same container for a long time and you don’t want the growing medium changing in that time," he says.
"As soon as you add nitrogen or water to peat, it starts to degrade faster — and the cellulose and lignin content in coir ensures that it’s free-draining. After six months, the air porosity of peat is very different from coir."
He also emphasises recent technical advances. "All good coir suppliers have research and development programmes, leading to more and more different mixes, with their own fibre content and particle size. There’s no point in having the top
too dry and the bottom too wet — you want it consistent throughout — and the industry as a whole has got better at addressing these issues.
"If we lost peat tomorrow that would be problematic — there isn’t the processing capacity immediately available. But in coir that capacity is still growing hugely. It’s essentially a by-product of a by-product. Coir pith from coconuts is used to make ropes and mats, but that only accounts for some of the husk waste from the coconut industry, and only some of that then goes to horticultural coir."
More than a hundred countries have a coconut industry, but only a few produce coir pith from the husks, de Vesci points out. "The rest just rots back into the ground. South-east Asia, Africa and South America haven’t yet focused on coir’s potential as a growing medium."
A "huge amount" of coir is already used elsewhere in northern Europe where the environmental argument about peat isn’t made, he maintains. "They buy it because of what it will do for them as growers," he says, adding that other countries such as Spain and Australia, where there are no ready reserves of peat and growing media has to be imported anyway, also favour coir over peat.
Peat still has a role in the industry, de Vesci believes. "Working with other growing-media firms including Ireland’s Bord na Móna is an important part of what we do," he says. "But most peat suppliers are engaging with Defra and they are researching alternatives."
Other established peat product suppliers such as Northern Ireland’s Westland and Klasmann Deilmann in Germany are also diversifying into alternative media, as well as, in the cases of Klasmann-Deilmann and Bord na Móna, into renewable-energy production.
Looking to the future, de Vesci points out a perhaps surprising use for coir as a growing medium. "What’s exciting for people like salad growers is the challenge of growing food in limited space — for example, by stacking up multiple levels lit by artificial light," he says.
"There are a number of interesting projects of this sort that are using coir and we are working with some multinational food companies on this, though we can’t say who right now. Coir might seem dull but really it’s exciting stuff."
Improving product quality
Leicester-based Petersfield Growing Mediums has "banned" green waste in its growing-media mixes, including retail products from this winter. The benefits are already being seen, according to sales and marketing manager Neil Williams (pictured).
"We ran into problems with crops that wouldn’t grow, but when we banned green waste the problems went away. It’s variable depending on the time of year. Our lab tests were showing spikes in sodium, even of boron. Then there were worries of pesticide carry-over. We saw one crop that had what looked a lot like glyphosate damage. Growers can’t afford such losses.
"Something fundamental has to happen to the feedstock if it’s to be turned into growing media. You’d be better growing a dedicated feed crop from scratch."
But he adds that the quality of growing media derived from wood fibre has increased significantly while costs have lowered as volumes have risen. "You get the quality from virgin wood, not from pallets," he adds. "You can only use it up to a certain percentage — 10-25 per cent depending on the crop. But early adopters who have trialled it have been very pleased."
Price, with all such developments, remains key. "If you’re asking 10 per cent more for a mix, convincing the grower of the benefits will be a hard sell," he says.
The coir industry, meanwhile, "has grown up a lot" in the two decades that Petersfield has been using it, adds Williams. "We used to be very nervous and tested every batch."
The company has recovered from the twin setbacks last year of losing sales manager Chris Husband and a fire that destroyed its warehouse shortly after. "We have bounced back and are within a couple of percent of where we were before," says Williams. "We have very loyal customers but you need the product quality to ensure repeat business."