Exploring Bio-Based Surfactants in Crop Protection and Plant Health Applications

Surfactants can help address some of these challenges by influencing how spray solutions behave and interact with plant surfaces. As formulators look for ways to balance performance and sustainability, interest in bio-based surfactants continues to grow. But what exactly makes a surfactant bio-based, and where can these ingredients fit into crop protection and plant health applications? Understanding their chemistry, applications, and key formulation considerations can help determine where these technologies may offer value.

What Do Surfactants Do in Agricultural Formulations?

Surfactants are ingredients that influence how liquids interact with surfaces and with other materials. A simple example is oil and water: because the two liquids do not readily mix, a surfactant can help bring them together and stabilize the resulting mixture. In agricultural formulations, they can modify properties such as surface tension, wetting, spreading, emulsification, and dispersion. These functions can influence how a spray solution behaves before and after it reaches the plant.

In agricultural applications, surfactants can help:

• Improve wetting and spreading: Spray droplets spread easily across foliage for more uniform coverage when incorporated with the right surfactant
• Support ingredient delivery: Surfactants can influence how active ingredients interact with and remain on plant surfaces.
• Promote dispersion: Formulation components can remain more evenly distributed throughout a product or spray mixture when the appropriate surfactant is used.
• Facilitate emulsification: The right surfactant can help ingredients that do not readily mix form a more stable mixture.

Surfactants may be incorporated directly into a finished formulation or added separately to the spray tank as an adjuvant. While both can influence spray performance, formulation surfactants are designed as part of the product itself, whereas in-tank adjuvants are added at the time of application to modify the properties of the spray mixture.

What Makes a Surfactant “Bio-Based”?

Bio-based surfactants are made using renewable or biologically derived feedstocks rather than relying solely on conventional petrochemical sources. But bio-based and biosurfactant are not necessarily interchangeable terms.

The distinction comes down, in part, to how the surfactant is produced:

• Bio-based surfactants can be produced through chemical processes using renewable feedstocks.
• Biosurfactants are generally produced by microorganisms, often through fermentation.

This distinction can matter to formulators because the production process can influence factors such as scalability, consistency, cost, and supply. For example, Integrity BioChem (IBC), a Palmer Holland principal, develops bio-based surfactants using scalable chemical processes rather than fermentation. Bio-based chemistry offers formulators a way to incorporate renewable feedstocks while maintaining the performance characteristics required for agricultural applications.

Where Bio-Based Surfactants Fit in Crop Protection & Plant Health

Bio-based surfactants can serve a range of roles in agricultural formulations and applications. While the specific function will vary depending on the formulation and intended use, their ability to influence how ingredients interact with water, surfaces, and one another makes them useful across several areas.

In-tank adjuvants

In-tank adjuvants are added to a spray solution before application to optimize the mixture’s behavior under field conditions. Surfactants may influence droplet size, wetting, spreading, and retention, helping the spray interact with plant surfaces and supporting more consistent deposition.

In-can formulation surfactants

Unlike in-tank adjuvants, in-can surfactants are built into the agricultural product during formulation. Their role may include helping otherwise incompatible ingredients work together, maintaining uniformity, and supporting the physical stability of the finished product throughout storage and use.

Foliar applications

For foliar applications, the interaction between a spray droplet and a plant's leaf surface can influence how effectively an active ingredient is delivered. Surfactants can help droplets wet and spread across foliage, potentially improving coverage and supporting more consistent deposition. Factors such as leaf structure and surface characteristics can also influence how a particular surfactant performs.

Soil and plant-health applications

Surfactants aren't limited to applications involving leaves. They can also be used in soil and plant-health products, including wetting agents, fertilizers, and biological formulations. In these applications, the objective may be to improve water distribution, help ingredients interact with the surrounding environment, or address specific formulation challenges.

Why Plant Surfaces Matter

Once a spray droplet reaches a plant, the characteristics of the leaf surface can influence what happens next. Leaves are not uniform, and several factors can affect how readily a droplet wets and spreads across the foliage, including:

• Surface waxiness: Waxy or hydrophobic surfaces can make it more difficult for water-based droplets to wet the leaf. Crops such as cabbage, broccoli, and other brassicas can have highly waxy leaf surfaces that cause droplets to bead rather than spread readily.
• Leaf texture and structure: Differences in surface features can affect how droplets spread and where they are deposited. For example, leaves with fine hairs, rough or uneven surfaces, or other structures can interrupt droplet movement.
• Environmental conditions: Temperature, humidity, and other field conditions can influence droplet behavior after application.

Surfactants can help manage these interactions by changing how the spray solution behaves when it contacts the plant. Improved wetting and spreading can increase the area covered by a droplet, while appropriate retention can help keep ingredients on the intended surface.

For formulators, recognizing the relationship between a spray solution and the plant surface is an important part of selecting surfactant technologies for a specific crop protection or plant-health application.

What Should Formulators Consider When Evaluating Bio-Based Surfactants?

With multiple surfactant technologies available, identifying the right option starts with understanding the needs of the formulation and its intended application. A bio-based designation alone does not determine whether a surfactant is the right fit. Instead, formulators should look at the ingredient as part of the complete formulation and consider several factors:

• Application: What is the surfactant expected to accomplish, and where will the product be used?
• Performance: Does it provide the desired wetting, spreading, dispersion, or delivery characteristics?
• Compatibility: How does it interact with the active ingredient and other formulation components?
• Stability: Can it maintain its intended performance throughout storage, handling, and use?
• Regulatory requirements: Is it appropriate for the intended agricultural application and market?
• Supply: Can it be sourced consistently at the scale required?
• Sustainability: What renewable feedstocks and manufacturing considerations contribute to its bio-based profile?

Looking at these factors together can help identify technologies that align with both formulation requirements and broader product development goals.

From Chemistry to Crop Performance

Choosing a surfactant is only one part of developing a successful agricultural formulation. Having the right technical resources and industry expertise behind that decision can be just as valuable. Palmer Holland works with formulators to connect the right specialty chemical technologies with specific formulation needs, helping turn emerging chemistries into practical opportunities.

Through our partnership with Integrity BioChem, Palmer Holland can help agricultural formulators evaluate bio-based surfactant technologies across crop protection, nutrition, and biological applications. Connect with our team to discuss your formulation needs and explore where bio-based surfactants may fit.