Agriculture is one of the largest plastic users in the world, but it is also one of the least visible.
Plastic mulch films, seed coatings, irrigation pipes, silage bags, nursery pots, and packaging collectively produce millions of tonnes of plastic waste every year, much of which ends up in the ground, breaking down into microplastic pollution, affecting the soil, the food chain, and the environment.
As per PMC (2025), human exposure to microplastic in the food chain is currently above 50,000 particles/year, which has been shown to induce an inflammatory response after ingestion. And the amount of plastic waste from the demand for packaging alone is over 100 million tonnes, producing 1.8 Gt of CO₂ eq emissions annually, as per PMC Polymers (2025).
Biopolymers in agriculture: biodegradable, bio-based materials derived from natural feedstocks are emerging as the science-backed solution to this crisis.
What Are Agricultural Biopolymers?
Biopolymers are defined as natural polymeric materials, such as plant-derived, animal-derived, or microbial-derived, that can break down into natural product.
The classes of biopolymers primarily used in agriculture include:
PLA (Polylactic Acid): is produced from corn or other types of starch; it is clear or translucent, rigid, and compostable.
PHA (Polyhydroxyalkanoates): are polyesters produced by fermentation of sugar and starch; they can be completely degraded in soil.
Starch-based systems (TPS): they are thermoplastic starch materials which are the most commercially advanced of the biopolymers in terms of mulching.
Chitosan: this type of biopolymer comes from the exoskeletons of shellfish/seafood; it is antifungal, can form films, and encourages plants’ immune system response.
Cellulose derivates: derived from agricultural crops such as rice husks, corn stover, and other agricultural by-products; they are often used to create structural packaging and films.
Biodegradable Mulch Films: The Biggest Opportunity
Biodegradable mulch film is the area that biopolymers are making the most immediate impact within agriculture; this is reflected in the current market status.
As per a recent report published by Grand View Research, the global biodegradable mulch films market size was estimated to be worth USD 50.75 million in 2024 and is projected to grow with a CAGR of 8.9% and reach a value of USD 82.82 million by 2030. In 2024, the Asia Pacific Region will hold 62.36% share of the biodegradable mulch films market primarily due to China’s enforcement of laws pertaining to agricultural plastic waste.
Why do biodegradable mulch films matter? Because using polyethylene (plastic) to make weed-suppressive, moisture-retaining, temperature-stabilising mulch films is a good thing for crops, but when we no longer need them, we cannot remove all of those plastic polyethylene mulch films from our fields. Their results are typically left on the field, and they break down into microplastics and remain in the soil for many years.
Biopolymer alternatives deliver the same agronomic performance and then disappear:
Starch-based films (TPS): held 61.25% market share in 2024; degrade into harmless CO₂ and water in soil.
PLA/vegetable waste composites: tensile strengths of 10–24 MPa and elongation up to 460%, comparable to conventional PE films, as per ACS Applied Materials & Interfaces (2022).
PHA films: fully biodegradable in soil, projected to grow at 9.10% CAGR, as per Precedence Research (2025).
Next-gen smart mulch films: USDA-funded research (2024) is developing PLA/PHA films that simultaneously suppress weeds, regulate soil temperature, and slowly release fertiliser into the root zone turning mulch film from a passive cover into an active agronomic input.
Chitosan and Biopolymer Seed Coatings: From Microplastic Problem to Crop Solution
Hidden sources of microplastics in agriculture include seed coatings. Conventional seed coatings consist of petroleum-based polymers (PEG, PVOH), which contribute directly to microplastic pollution in the soil, as microplastics are released into the soil during planting with seed coatings.
Biopolymer seed coatings offer a direct replacement and deliver additional agronomic benefits that synthetic coatings cannot:
Chitosan seed coatings can initiate plant immune responses by activating defense pathways, and can promote seed germination, and will inhibit pathogen growth, including Fusarium, Macrophomina, and Aspergillus niger (PubMed, 2024).
Biopolymer seed coatings made from electrospun PLA/cellulose blend nanofibers can provide controlled release of agrichemicals around the roots of newly emerging seedlings, providing precise timing for the release of fungicides or beneficial microbes as the seedling begins to grow (ACS Sustainable Chemistry & Engineering).
Alginate and chitosan seed coatings containing Trichoderma harzianum can maintain a viable population of biocontrol agents for 6 months at 30°C, providing extended disease control in oilseed crops (PubMed, 2024).
As per Plastics Engineering (2025), researchers have identified polysaccharide and protein biopolymers that comply with EU REACH regulations, demonstrating good adhesion, dust reduction, and maintained seed physiological quality the core performance requirements for commercial adoption.
Biopolymers from Agricultural Waste: Closing the Circular Loop
A striking thing about biopolymers and their use in agriculture today is that they originate from agricultural produce.
Agricultural waste comes to approximately 998 million tonnes of material per annum (i.e. rice husks, corn cobs, fruit skins, crop stalks). The majority of this waste will either be disposed of in landfills, set fire to or allow to naturally decompose. However, these agricultural residues are now converted into functional biopolymer packaging and mulch material following the alkaline, enzymatic and/or solvent-based extraction of cellulose, starch or pectin.
A specific example of this activity would be the use of PLA composite resins, which contained 10-30% spinach stems, tomato pomace or cocoa shells to provide mechanical properties sufficient for use as mulch and crop derived micronutrients within the biodegradable film allowing for the soil to receive nutrients from the breakdown of the film when it decomposes. The elegant circularity is that agricultural waste becomes agricultural input through biodegradable polymer manufacturing.
Biopolymer Performance Comparison for Farming Applications
|
Biopolymer |
Agricultural Application |
Key Benefit |
Limitation |
|
TPS (Thermoplastic Starch) |
Mulch films |
Lowest cost, degrades in soil |
Lower moisture resistance |
|
PLA |
Mulch films, packaging |
Good tensile strength, transparent |
Requires industrial composting |
|
PHA |
Mulch films, coatings |
Full in-soil biodegradation |
Higher production cost |
|
Chitosan |
Seed coatings, fungicide carrier |
Antimicrobial, immunity activating |
Moisture sensitive |
|
Cellulose (nanofibre) |
Seed coatings, barrier packaging |
High tensile strength (+90%), low WVTR |
Processing complexity |
Frequently Asked Questions About Biopolymers in Agriculture
Q: What is the difference between a biopolymer and a bioplastic in agriculture?
Biopolymers are those raw materials, such as PLA, PHA, starch, chitosan, and cellulose, from which bioplastics are derived. Bioplastics, on the other hand, refer to those materials derived from biopolymers, such as mulch films, seed coatings, and pots, among others. However, all bioplastics are derived from biopolymers, and not all biopolymers are used to derive bioplastics.
Q: Do biodegradable mulch films work as well as polyethylene?
Yes, biodegradable mulch films perform as well as PE films in terms of weed suppression, moisture retention, and soil temperature control, based on multiple field trials conducted on PLA/vegetable wastes, with elongation rates of up to 460% and water vapor permeability similar to those of conventional Mater-Bi films, as published in ACS Applied Materials and Interfaces (2022).
Q: Are biopolymer seed coatings approved under EU regulations?
Polysaccharide and protein-based biopolymer coatings for seeds are currently being validated under EU REACH regulations, with a majority showing complete compliance, while maintaining comparable performance to those coated with microplastics, as published in Plastics Engineering (2025).
Q: Can agricultural waste be used to make biopolymers?
Yes, rice husks, corn cobs, fruit peels, and crop residues can be utilized as active agricultural waste in biopolymer production, including cellulose, starch, and pectin production. The global agricultural waste has 998 million tonnes of annual feedstock availability for biopolymer production, making circular economy integration feasible.
The Bottom Line
Agriculture has reached an era where biopolymers are no longer an experimental product. Rather, the market, scientific findings, and the regulatory environment are all indicating one result that there is a need to transition away from petroleum-based plastic use in the world of agriculture. As such, biopolymers are the most technologically advanced and accessible solution for the current crop of farmers.
There are numerous biopolymers currently being developed to replace plastic in the world of agriculture. These include biodegradable mulch films, biodegradable chitosan-based seed coatings to stimulate the immune system, and biodegradable cellulose-based packaging using agricultural by-products.
Plastic is no longer the future.
Everything grown from the earth is!
