Obstacles to the use of biodegradable mulching

The challenges that agricultural production had to face over the last decades have led many companies and producers to look for increasingly sustainable and environmentally friendly alternatives that also allow them to maintain the quality levels of the crops. For that reason, although biodegradable plastics are currently gaining more followers, the truth is that there is still some resistance when it comes to their use in agricultural production.

First, some background

From the time when agriculture acquired a commercial character, most farmers began to use plastic films to improve the quality of their crops and increase production.

Therefore, in the 1950s, polyethene plastic mulching made from non-renewable oil became popular, as a key piece for the cultivation of fruits and vegetables, thanks to its availability, ease of mechanical application or use and other benefits such as the capacity to control weeds, modify the temperature of the soil, minimize the leaching of nutrients, reduce the damage caused by insects, improve plant growth and accelerate the maturity of crops, among others.

However, over the years and due to the new challenges that emerged, such as climate change, many companies and farmers are looking for more environmentally friendly alternatives, which allow maintaining the quality of crops, while almost completely reducing plastic waste once the harvest season is over.

After several investigations and tests, diverse companies and laboratories managed to create plastics with biodegradable qualities. These plastics are designed to decompose as the growing season of the crop is over, serving as fertilizer for the land and thus omitting the process of elimination of conventional mulching that, although economical, is environmentally expensive.

According to information published in the website Cambridge Core, usually, the costs to remove and transport used polyethene plastics to another place can be more than $250 per hectare ($100 per acre). In the worst case, used mulching plastic is usually burned, buried, or dumped in landfills.

Likewise, while the recycling of agricultural plastics has experienced remarkable growth, is not an easy task due to the dirt it brings from the fields, the lack of specialized packaging equipment, the long distances to the recycling facilities; in short, its high cost.

What cannot be denied is that, although biodegradable mulching is more expensive at the time of purchase compared to conventional polyethene mulching, in the long-term biodegradable mulching can be considerably cheaper when the costs associated with the removal and transportation of the remaining material are considered.

Obstacles to the use of biodegradable mulching

Why are there obstacles to using biodegradable mulching?

Compared to conventional plastics, biodegradable mulching is relatively new. They were introduced in the 1980s as a more sustainable and eco-friendly option to polyethene films.

However, despite their benefits such as the ability to grow in the soil, become fertilizer at the end of the harvest season, and reduce labour and environmental costs related to the elimination of plastic, currently, some prefer to continue using conventional plastics.

Why does this happen? Some of the main obstacles that explain the reluctance to using biodegradable mulching, in some cases, could be due to a lack of knowledge of the benefits of these plastics, thinking that in the long term it will end up being more expensive or because their decomposition process can become unpredictable.

Also, there has been some difficulty in finding a consensus when it comes to categorizing these films as degradable or biodegradable. As an example, USDA-certified organic producers cannot use biodegradable mulch products as it’s prohibited.

According to information published in the website Cambridge Core, based on the current rules of the U.S. National Organic Program (NOP), certified organic producers can use polyethene plastic as mulch if the plastic is removed at the end of the growing season. On the other hand, organic producers cannot use biodegradable plastic cover products, because these products don’t meet the NOP 29 standards.

However, the National Organic Standards Board (NOSB) passed a motion in 2012 to recommend the allowance of biodegradable biobased mulch films that are produced without organisms or feedstock derived from excluded methods, for example, genetically modified organisms, and fully biodegradable (an estimated 90% biodegradation in soil within 2 years). This type of concessions is considered by the NOSB as an excellent alternative to reduce pollution, without sacrificing the principles of organic agriculture.

The European Union approved in 2018 the EN-17033 “Plastics – Biodegradable mulch films for use in agriculture or horticulture – Requirements and test methods,” which standardized the use of these biodegradable mulch in agriculture. Last year the State of California approved the use of biodegradable mulching:

• https://www.packaginglaw.com/special-focus/california-sinks-%E2%80%9Marine-degradable%E2%80%9D-plastic-claims
• https://ucanr.edu/blogs/blogcore/postdetail.cfm?postnum=43880

What can be done to overcome the obstacles to biodegradable mulching?

One of the alternatives that many companies and farmers are applying to break down the barriers to using biodegradable mulches is to inform and educate other farmers about the environmental implications of using these mulches and help them understand that the use of these plastics has more advantages than disadvantages.

For example, when biodegradable mulching is used, there is a noticeable reduction in plastic waste that, with other plastics, can cause considerable (even irreversible) damage to the environment.

In addition, it is crucial to awaken greater interest in farmers, who have not yet entered the era of biodegradable plastics, so that they can learn about the materials used in their manufacture and the benefits they bring to their economy, their crops and the agricultural environment.

Some emphasize the need for sociological research to complement field studies on the performance of these mulches to explore the experiences and perceptions of stakeholders with biodegradable mulch.

One of the measures being implemented today is to conduct surveys and focus groups to explore the reluctance to the use of biodegradable mulch, as well as to establish the necessary bridges that will allow the use of biodegradable mulch to be adopted as something usual, leading to innovation and development of new biodegradable plastics.

Currently, scientists and researchers are continuously developing and evaluating new types of biodegradable mulching. To learn more about biodegradable mulching, we recommend watching our webinar on its benefits and profitability.