Agricultural film has increased in popularity, despite the criticisms surrounding the use of plastics in the environmental debate.

Demand for plastics for agricultural usage in the film area was 3.6 million tonnes in 2008, according to Andrew Reynolds of Applied Market Information, who spoke at the 2009 AMI conference on agricultural film, held in Barcelona in February.

Specialists argue that such products extend the growing season and raise yield, which is critical as the population grows and the area being farmed remains static.

Agricultural Film 2009 attracted delegates from around the globe and generated extensive debate on ways to develop the best film technology for the horticultural industry.

Researcher CSIC puts the area under film in the Mediterranean at 400,000 hectares, with 80,000ha of vegetables in Spain (tomatoes, peppers and lettuce).

Pliant Corporation cites pest control as the main reason for a significant use of such products in the US, where it is produced from materials such as EVOH and nylon. Around 2.5 per cent of the film used in the US is biodegradable.

The product, “biolice”, was compared with PE film as an option and average temperatures in mulch were the same. It has been used in short-term crops such as maize, cotton and salad; longer term films are under development for tomatoes and melons.

Alternatives to established methods are being looked at - heat control has been examined by scientists at BASF as the main markets for agricultural film are in the tropics and sub-tropics, where the summer months are too hot for cultivation.

Improving greenhouse film properties can extend the growing period. The additive Lumogen IR 1050 works by reflecting infrared and allowing visible light to pass for photosynthesis.

But the event closed with the reassurance that horticultural film is being recovered and recycled at an increased rate with grinders, shredders and pulverisers to break down material for recycling.

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