Using coir as a growing susbstrate - sustainably and ethically
Manufactured from the inner husk of coconuts, coir is, but its very nature, produced in distant, and often developing, countries. This means that there is also an ethical slant to consider, as well as the question of shipping costs and carbon use.
As retailers apply more pressure on their suppliers to focus on sustainability and ethics, these points are becoming increasingly important. Growers not only require a high-quality product that will produce top yields and quality, they also need to know that it also meets the green requirements of supermarkets. Sandy Booth, managing director of the New Forest Fruit Company, has been using coir for more than 10 years at Newhouse Farm, Brockenhurst, Hampshire, and is confident that it fits in with his responsible farming policy. “Soil sterilisation was becoming more and more difficult, so we moved from soil to peat, and then to coir,” he says. “The quality of coir has improved tenfold over that time – it used to have a very high salt content, and some still has if it’s not washed properly. That is the biggest problem you can encounter, so you need to make sure it is well produced and quality controlled.”
Sandy Booth visited the Botanicoir facility in Sri Lanka earlier this year, to learn more about how coir is produced. “The whole system of harvesting and processing coconuts was fascinating,” he says. After harvest, the husk is taken to a fibre mill and the waste is processed into coir by being washed, buffered, dried, graded and then pressed into bags. “It is a third-world country, so it’s not very mechanised – although Botanicoir is looking to change that,” says Sandy. “But the welfare of the workers is very good. There is very low unemployment in Sri Lanka so they have to look after their employees. The company pays for all their meals when they’re working, and education for their children – it was quite an eye opener.”
Sandy continues the high welfare policy at Newhouse Farm, where he employs seasonal labour from Eastern Europe, Poland, Romania and Bulgaria. “We pay and look after them well; that way their family and friends come back year after year, which is what we want. In everything we do, the clear objectives of the business are to be professional, responsible and progressive – and we take pride in the quality and provenance of our fruit.”
But is shipping coir from the other side of the world really responsible? Sandy certainly thinks so. “It is a waste product which lasts for four years, rather than peat which lasts just one. That makes it sustainable,” he says. “If we were still buying peat we’d get 100 bags on a pallet. We need 6250 bags/ha – that’s 62.5 pallets, which is a lot of transporting. With coir we get more than 600 bags on a pallet, so only need 10 pallets. That is a huge saving in transport use and cost.”
New Forest Fruit produces more than 2000 tonnes of strawberries and 100 tonnes of blueberries a year, which are sold principally through Sainsbury’s. Quality control is therefore absolutely critical. “For top quality fruit you need healthy plants – and if you don’t start off with the right growing media then you can’t grow the right plants,” he says.
With a long growing season, from April to November, Sandy grows in glasshouses for the first and last months of the season, and polytunnels for the main season. “Most of our strawberries are grown on a tabletop system so that they are picked without the back-bending traditionally associated with picking.”
He buys one metre bags of coir for strawberries, and pots for blueberries, planting in January, March and July. He uses drip irrigation with five drippers per bag, running at 1.2 to 2 litres per hour. “Most people have four drippers a bag, but we find five eliminates any potential salt problem,” he says.
In the past, he had occasional problems with poor coir structure, which led to rooting problems and poor yields. “You need the right balance of fibre and particle size to give the necessary aeration – without that it slumps and the roots can’t grow.” However, four years ago he switched to Botanicoir, and is very happy with the results. “We’ve now got the confidence to really more forward.”
Because coir is inert and doesn’t hold nutrients for long, growers have to feed the correct nutrients throughout, adds Sandy. “We use electronic tools to monitor the EC and pH of the coir, and analyse the leaves and fruit regularly as well.” At the end of the crop, the coir is flushed with water, the bags puffed to improve aeration, and the EC is below 1.0 before replanting. “We use them for three years in the glasshouses and four years in the polytunnels.” After that they can be composted or spread on land, rather than sent to landfill like rockwool. “It’s very cost effective and sustainable, and I’m extremely happy with the quality of my plants as a result,” said Sandy Booth.
Dennis Wilson, managing director of crop advisory and research company DLV Plant UK, says that the supply and grades of coir have grown dramatically as more soft fruit growers make the switch. “Knowledge of the differing physical properties and chemical processing required for different applications has expanded similarly,” he adds. “Different crops and growing systems require different physical specifications – fibre content affects water movement, while fine material adjusts water retention, for example.”
Some crops, like strawberries, have a very high calcium demand and require a well washed and buffered product, whereas other crops, like raspberries, need less calcium but more magnesium, says Dennis Wilson. “It is therefore vitally important that growers and their advisors work closely with reputable and reliable suppliers to ensure the correct grade of product is selected for the crop and growing system. Gone are the days when the cheapest product will suffice.”
Agrovista, one of the UK’s leading horticultural advice and supply companies, has worked closely with Botanicoir for the past four years. “The loss of soil sterilants, increase in picking costs and changes in planning laws have all conspired to drive the move from soil to substrate,” says Mark Davies, head of Agrovista’s soft fruit business. “The product we started with four years ago was, I believe, the best available. However, we have not stopped trying to continually develop the coir’s physical and chemical qualities. Trial work with some of our key growers has led to the development of Botanicoir Precision Plus product, which has seen some growers produce their best crops ever this year, despite the weather conditions.”
Precision Plus contains a blend of different particle sizes, to ensure excellent drainage, air-filled porosity and water/nutrient holding capacity as well as long-lasting structural integrity, says Botanicoir managing director Kalum Balasuriya. “Good drainage is very important for root development. We have different products for different crops- it’s important to select the right coir for your needs.”
As a family business, quality control is integral to the company’s ethos, he adds. “Everyone is very hands-on, and we hire top international consultants to train our staff in quality control. We have our own laboratories to test pH and nutrients levels and use a leading Dutch laboratory to check random samples weekly. Having these checks and balances is critical to the success of our product.”