Commercial and heavy-duty fabrics are used extensively in both the construction and sports care industries, and HW readers will know many of the products serving these markets. But it is the wide range of horticultural fabrics that most of us will be familiar with, including the weed control and ground cover fabrics; crop covers and fleeces; shading and sheltering fabrics; and the biodegradable mulches.
The past decade has seen some revolutionary improvements in the capabilities and production of horticultural fabrics, none more so than the development of biodegradable mulches. Horticultural sales manager Nick Hammond of Bristol-based Tildenet says: "The past couple of years have seen phenomenal sales growth in biodegradable mulches.
There is an ever-growing demand, particularly from growers, who want to be seen to be environmentally conscious, but also want to save a bit of money."
The cost efficiency comes from the fact that after a few months the material biodegrades, which means there are no removal, disposal or storage costs.
The subject of disposal and, ultimately, the avoidance of it through recycling or biodegradability, is an industry "hot potato", with growers coming under increased
pressure to reduce disposal rates — a situation that has existed for some time in heavy industry, says Hammond.
DEFRA’s Waste Strategy 2000 set a target of 67 per cent recovery of waste by 2015, through recycling, composting, incineration and other energy-from-waste systems. This is going to put more reliance on biodegradable fabrics, such as Tildenet’s BioTelo — a 100 per cent biodegradable film made from maize starch that maintains its mulching ability for a minimum of one and a half months, and a maximum of four and a half months in the case of autumn cycles.
BioTelo comes in 500m rolls and is available in two thicknesses, which determine its life expectancy. It has the same characteristics, resistance, elasticity and mulching efficiency as polyethylene films and can be laid using the usual machines and automatic transplanters.
The Mater-Bi biodegradable film from Nottinghamshire-based Capatex is similar. In contact with normal soil moisture and micro-organisms it starts to biodegrade, eventually breaking down to form water and carbon dioxide.
Similar again is the relatively new Biolene black mulch material available from Ilex Organics of Market Rasen, Lincolnshire — a subsidiary of Growing Technologies (GT) based in Derby. GT managing director Mike Spencer says: "
This non-GM starch-based product is very much a key part of our portfolio. We spent a year trialling it. It is available in two grades: Biolene A has a maximum life expectancy of 16 weeks, and Biolene B, 26 weeks. It is relatively expensive to produce, but you have to weigh this against the cost or lifting and disposal."
With other products, such as British Polythene Industries’ (BPI) Visqueen EcoMembrane — made from packaging waste — and Capatex’s EcoPac Paper Mulch, the industry is taking significant steps towards solving the waste problem. But there are still concerns that the targets will be hard to meet. Capatex director Peter Strauss says: "Products such as netting and windbreaks often come in small quantities, making recycling unviable."
A top-selling conventional mulching fabric is MyPex, from GT. Spencer says: "It represents the best engineered-for-purpose solution to weed control, and our volume sales of it increased in 2006 by almost 25 per cent."
MyPex’s distinctive green-and-white- striped woven construction combines weed suppression with good water permeability. At 105g/sq m, it is, says Spencer, ideal for using in the production of bedding and pot plants, container stock and food crops, as well as for use outdoors, in polytunnels and glass-houses, on benches, and in capillary, sand and gravel beds. The company also sells the slightly thinner Red Stripe landscaping fabric from MyPex.
The greenhouse environment is where white fabrics come into their own. Salad growers benefit from earliness promoted by the light-reflective nature of white materials. This is not, as yet, a significant practice within the ornamentals sector, but in some situations — pot plants and bedding, for example — the increased light reflected on the undersides of the leaves could be an advantage.
At this time of year, however, the market demands are not so much for mulching materials but fleeces and covering systems. Tildenet’s Hammond says: "In the early part of the year we are inundated with requests for spunbonded fleece. We sell around nine million square metres of it annually. It works like a protective duvet for plants, maintaining a temperate microclimate while protecting from frost, snow, hail, rainbeat, slugs, snails and some insects."
Tildenet markets Thermagro, which can be used all year round and allows for earlier and maximised crops. "Every roll is individually UV treated and it has a high tension tear resistance, which means that it is very durable," Hammond explains.
Owing to the pounding horticultural fleeces get from the elements, and the variable ways in which they are stored when not in use, they rarely survive more than three or four seasons, some significantly less.
Associate director Brian Calder of Lows of Dundee argues that the fleece market is very price-driven. "It is highly competitive, with lots of manufacturers producing much the same thing, so in terms of attracting business, it usually comes down to a matter of pricing," he says.
Lows produces fleeces with an extra-strong patented seam. Calder says: "Many growers who have bought cheaper fleeces, especially the wider width types, have discovered that the seams come apart. These will almost certainly have been glued, and the glue has perished. We utilise a bonded crop-stitch seam that reduces the risk of separating and helps prolong the life of the product."
One of the first fabrics used in horticulture was glasshouse capillary matting. It is still used by growers, but with more sophisticated, automated, timed watering systems, and better shading technology, the need for capillary matting has declined. The indoor matting usually weighs around 250g/sq m. Outside, standard matting is heavier, at 350g, and premium outdoor matting, at 475g. It is available in black and "natural" colours.