A Boost for Sustainable Agriculture: The Promise of the US “Plant Biostimulant Act”

In a welcome development for sustainable agriculture, United States Representatives Jimmy Panetta (CA-19) and Jim Baird (IN-04) have introduced the Plant Biostimulant Act of 2025; a bipartisan amendment to the Federal Insecticide, Fungicide, and Rodenticide Act (FIFRA) that could significantly reshape the regulatory landscape for plant biostimulants in the United States. Companion legislation has also been introduced in the Senate by U.S. Senators Roger Marshall (R-KS) and Alex Padilla (D-CA).

What are plant biostimulants?

Plant biostimulants are biological products which hold great potential in advancing sustainable agricultural practices by enhancing plant growth and resilience.  Under the proposed amendments “plant biostimulant” is defined as a substance, microorganism, or mixture thereof, that, when applied to seeds, plants, the rhizosphere, soil, or other growth media, act to support a plant’s natural processes independently of the biostimulant’s nutrient content, including by improving nutrient availability, uptake or use efficiency, tolerance to abiotic stress, and consequent growth, development, quality, or yield¹. They include living organisms, such as bacteria, fungi, plants and algae, as well as extracts from them, such as amino acids, sugars, or compounds that result from their decomposition, such as humic or fulvic acids. Some biostimulants find utility as soil improvers, increasing the amount or availability of nutrients in the soil, but they can also act more directly, for example, as catalysts, triggering or enhancing various endogenous plant processes like root development, nutrient uptake, photosynthesis, and pathogen or stress resistance pathways.

As a result, biostimulants can lead to higher yields, improved crop quality, greater disease resistance, stress tolerance and enhanced resource usage. All of which are critical in meeting the challenge of maintaining adequate levels of food production in a changing climate, whilst simultaneously reducing reliance on synthetic chemical fertilisers and pesticides.

Why is the proposed amendment significant?

Rather than creating a standalone legislative instrument, our understanding is that the proposed amendment to the existing FIFRA legislation seeks to integrate plant biostimulants into the existing regulatory framework and aims to establish a uniform federal definition for plant biostimulants, and a standardised, science-based process for approving these products for commercial use. We also understand that the amended legislation would require the United States Department of Agriculture (USDA) to examine the contributions of a plant biostimulant to soil health and sustainability. The move is being interpreted as a major step toward recognising plant biostimulants as mainstream biological alternatives to synthetic pesticides and fertilizers and, crucially, creating a clear regulatory pathway for their commercialisation.

The amendment aims to provide some welcome clarity for both producers and investors alike, who have long faced uncertainty due to the lack of a formal regulatory definition or pathway to market for biostimulants. By addressing this gap, the amendment could unlock new opportunities for innovation and investment in the sector and allow the benefits of these technologies to be realised.

Importantly, the bill enjoys bipartisan support, which signals strong momentum and cross-party recognition of the role biostimulants can play in advancing soil health, improving water quality, reducing agriculture’s environmental footprint and in boosting the hard-pressed armamentarium of fungicides and pesticides.

If passed, this legislation is expected to catalyse a more robust commercial environment for biostimulants, encouraging further research, development, and adoption of these promising technologies. It’s certainly a positive signal that U.S. agriculture is ready to embrace a more sustainable and biologically driven future.

What are the possible implications?

One consequence of this amendment would be that two of the world’s major markets – Europe and the US – would be more closely aligned in their definition of plant biostimulants and in providing a favourable regulatory environment for them.  

Europe has to some extent led the way on this issue. The EU’s Farm to Fork Strategy, which was introduced in 2020 in order to accelerate Europe’s transition to a sustainable food system, for example by reducing the use and risk of chemical pesticides by 50% by 2030², has provided the policy context for a regulatory landscape which encourages the use of biostimulants as alternatives to traditional agrochemicals. The last few years have seen a steep upward trend in the number of marketing authorisations issued for microbial biostimulants and biocontrol agents in particular, and the European agricultural biologicals market is predicted to increase from 6.5 billion in 2023 to over 10 billion in 2033³.  

Europe currently  operates a twin-track regulatory process with biostimulants regulated by the Fertilising Products Regulation (FPR)⁵, and plant protection products (PPPs, which encompass pesticides, fungicides, insecticides, herbicides and weed killers) protected under separate legislation⁶.  

The differing regulatory pathways for biostimulants and PPPs in Europe (with biostimulant regulation generally being considered less onerous) does have the potential to create some regulatory ambiguities for biological agents which possess both biostimulant and biocontrol properties.  It therefore seems that for some biological agents, the regulatory requirements that need to be satisfied may differ depending on the mechanism of action of the product, and crucially whether or not the mechanism is known.  However, this is an emerging area and it is likely that the regulations may still need some refinement to ensure that products reaching the market are safe and effective to use and do not have unintended effects.

As the biostimulant and biocontrol market continues to grow, intellectual property protection covering biostimulant and biocontrol products is likely to become increasingly important, not least because these are likely to be straightforward for would-be competitors to reverse engineer.  This is especially the case for products containing living or dormant microbial organisms.

Patenting key microorganisms can therefore offer very valuable protection for companies operating in this area. It can, however, be complex, with specific and sometimes very strict formal and substantive requirements needing to be satisfied, particularly in Europe.

1. Plant Biosimulant Act of 2025, A BILL, Sec 2 – Defining Plant Biostimulants, (pp), lines 14-25.
2. European Commission, 2025. Farm to Fork targets – Progress. [online] Available at: https://food.ec.europa.eu/plants/pesticides/sustainable-use-pesticides/farm-fork-targets-progress_en [Accessed 7 June 2025]
3. Spherical Insights, 2024. Europe Agricultural Biologicals Market Size, Forecast to 2033. [online] Available at: https://www.sphericalinsights.com/reports/europe-agricultural-biologicals-market [Accessed 7 June 2025]
4. Adopted in 16 July 2022
5. European Parliament and Council, Regulation (EU) 2019/1009 of the European Parliament and of the Council of 5 June 2019 laying down rules on the making available on the market of EU fertilising products and amending Regulations (EC) No 1069/2009 and (EC) No 1107/2009 and repealing Regulation (EC) No 2003/2003 [2019] OJ L170/1
6. European Parliament and Council of the European Union (2009) 'Regulation (EC) No 1107/2009 concerning the placing of plant protection products on the market and repealing Council Directives 79/117/EEC and 91/414/EEC'. Official Journal of the European Union, L309, pp. 1–50.
   

This blog was co-authored by our AgBiological specialists Louise Atkins and Ben Tolley. If you would like advice on how best to protect your biostimulants and biocontrol products, please reach out to them.