Why Some Pesticides Can Significantly Shorten the Life of Greenhouse Film
Updated: Oct 7
The Hidden Impact of Sulphur and Chlorine-Based Agrochemicals
Knowledge Centre | Greenhouse Film Science
The Question
Many growers expect a greenhouse film to last four, five or even more years. However, in some greenhouses, the film begins to lose strength, become brittle or fail much earlier than expected.
Why?
While sunlight is the primary cause of plastic ageing, certain agricultural chemicals can dramatically accelerate the process. Among the most significant are sulphur-based and chlorine-based crop protection products.
Numerous studies have shown that these chemicals can shorten the service life of greenhouse films by reducing the effectiveness of their UV stabilisation systems. (Acta Horticulturae)
The Science
Greenhouse Film Doesn’t Fail Because of UV Alone.
Modern greenhouse films are manufactured with specialised UV stabilisers.
These stabilisers act like a protective shield. Instead of allowing ultraviolet radiation to attack the polyethylene itself, the stabilisers absorb or neutralise the damaging effects of sunlight.
As long as this protection remains active, the film maintains its strength, flexibility and mechanical performance.
What Happens When Certain Agrochemicals Are Used?
Some agrochemicals, particularly those containing active sulphur or chlorine compounds, can react with parts of the UV stabilisation system used in many greenhouse films.
Rather than attacking the polyethylene directly, these chemicals reduce the effectiveness of the stabilisers. Once the UV protection is weakened, sunlight can begin degrading the polymer much more rapidly.
In other words:
The chemical doesn’t destroy the plastic overnight.
It weakens the film’s natural defence against sunlight.
After that, UV radiation does the rest. (ScienceDirect)
How Agrochemicals Accelerate Film Ageing
The diagram below illustrates why certain sulphur and chlorine-containing agrochemicals can significantly reduce the service life of greenhouse film.
The chemicals do not destroy the polyethylene directly.
Instead, they reduce the effectiveness of the UV stabilisation system, allowing sunlight to accelerate the ageing process.
Why Does Film Age Faster?
When the UV protection system is compromised, growers may begin to notice:
Reduced flexibility
Increased brittleness
Easier tearing
Lower mechanical strength
Reduced service life
This is why two greenhouses using the same film may experience very different lifespans, depending on the growing environment and crop protection programme.
Sulphur Is One of the Biggest Challenges
Sulphur-based products have long been recognised as one of the most aggressive chemical environments for polyethylene greenhouse films.
When sulphur is used frequently, especially under warm greenhouse conditions with limited ventilation, film ageing can accelerate significantly unless the film has been designed with sulphur-resistant stabilisation technology. (CORDIS)
It’s Not Just About the Film
Film life depends on many factors working together.
These include:
UV intensity
Greenhouse temperature
Ventilation
Frequency of chemical applications
Active ingredients in crop protection products
Quality of the UV stabilisation package
The same greenhouse film may perform very differently under different growing conditions.
Does every pesticide damage greenhouse film?
No.
Not every crop protection product affects greenhouse film in the same way.
The impact depends on the active ingredients, application frequency, concentration and greenhouse conditions.
Is sulphur always a problem?
Sulphur is an effective and widely used crop protection tool.
The issue is not whether it should be used. The important consideration is whether the greenhouse film has been designed to withstand repeated exposure to sulphur-containing environments.
Can better greenhouse films resist these chemicals?
Yes.
Some premium greenhouse films are formulated with UV stabilisation systems specifically designed to provide greater resistance to sulphur and chlorine-containing agrochemicals. However, even these films should be used according to the manufacturer’s recommendations, as no material is completely immune to harsh chemical environments. (ScienceDirect)
Aus Crop Cover Insight
When growers compare greenhouse films, they often ask about thickness, light transmission or diffusion. These are all important.
However, another equally important question is:
“What chemicals will this film be exposed to during its lifetime?”
Understanding the interaction between greenhouse films and crop protection products helps growers choose materials that are better suited to their growing system, not just on the day of installation, but for years afterwards.
At Aus Crop Cover, we believe that long-term performance is determined by more than just the film itself.
It also depends on understanding the environment in which the film will be used.
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