Agricultural Biostimulants: What They Are, Benefits, and How to Use Them Effectively
What Are Agricultural Biostimulants?
Composition and Natural Origin
Agricultural biostimulants are products formulated from natural substances such as plant extracts, beneficial microorganisms, amino acids, or humic compounds that act on the physiological processes of plants. Unlike fertilizers, they do not provide nutrients directly, but stimulate the plant’s internal mechanisms to enhance performance, resilience, and development.
Their natural origin and non-nutritive approach make them key allies of organic, regenerative, and residue-free agriculture. They are designed to boost crop vigor without disrupting the balance of the agricultural ecosystem.
Differences Between Biostimulants, Fertilizers, and Plant Protection Products
Biostimulants vs. Fertilizers: Complementary Tools?
Although they may seem similar, biostimulants do not replace fertilizers. While fertilizers provide essential nutrients like nitrogen, phosphorus, or potassium, biostimulants act as catalysts for natural processes such as nutrient uptake, photosynthesis, or stress resistance.
On the other hand, plant protection products are aimed at eliminating pests or diseases. Biostimulants, by contrast, improve plant health and strength, helping it defend itself in a natural and sustained manner.
Main Types of Biostimulants and Their Functions
Microbial, Humic, and Plant Extract Biostimulants
The most common types of biostimulants include:
- Microbial: based on beneficial bacteria or fungi such as mycorrhizae or rhizobacteria, they improve soil structure and nutrient absorption.
- Humic and fulvic compounds: derived from organic matter, they promote root growth and water retention.
- Plant extracts: such as seaweed or nettle, which provide natural phytohormones and antioxidants.
These products work synergistically with the soil and plants, maximizing yield without compromising sustainability.
Benefits of Using Biostimulants in Organic Agriculture
The most notable benefits of their use include:
- Increased tolerance to abiotic stress (drought, salinity, cold, or heat).
- Stimulation of both root and aerial development.
- Improved nutrient uptake and assimilation.
- Increased crop yield and quality.
- Reduction in the use of chemical products and residues.
Their eco-friendly profile makes them an essential tool for producers looking to stand out with responsible practices.
How to Apply Biostimulants According to Crop Type
Foliar vs. Root Application
The effectiveness of biostimulants depends on both formulation and method of application. There are two main approaches: foliar and root. Foliar application involves spraying directly onto the leaves, allowing for rapid absorption and making it ideal during critical stages such as flowering or fruit setting. Root application, on the other hand, is done via irrigation and supports root system development.
In short-cycle horticultural crops such as tomato or pepper, both techniques are often combined for optimal results. In woody crops such as olive or vine, root application is more common, especially in spring and summer.
Key Factors in Choosing a Good Agricultural Biostimulant
With a growing range of products on the market, it’s important to choose wisely. Here are some recommendations:
- Choose products certified for organic farming (EU standards, vegan or cruelty-free labels).
- Check the label composition: look for natural, traceable active ingredients.
- Review field trials or demo studies that support the product’s effectiveness.
- Prefer companies that offer personalized technical support to tailor usage to each crop and phenological stage.
In summary, an effective biostimulant is one that meets the needs of the soil, the crop, and the climate, while also respecting the environment and the farmer’s health.
Biostimulation is more than just a trend—it’s a real, effective, and sustainable tool to face the challenges of modern agriculture. Proper use enhances profitability, protects natural resources, and delivers healthier, higher-quality food.
What are agricultural biostimulants and what are they used for?
They are natural substances that stimulate physiological processes in plants, improving their growth, resilience, and productivity.
What is the difference between biostimulants and fertilizers?
Fertilizers provide nutrients directly; biostimulants activate internal plant mechanisms without supplying nutrients.
What are the most common types of agricultural biostimulants?
Beneficial microorganisms, seaweed extracts, amino acids, and humic compounds are the most commonly used in agriculture.
How are agricultural biostimulants applied?
They can be applied via foliar spray (on the leaves) or through the roots (via irrigation), depending on the crop and the desired effect.
What benefits do they offer in organic farming?
They improve nutrient absorption, reduce abiotic stress, increase yield, and help maintain healthy soils.
Are they safe for the environment and human health?
Yes. Well-formulated biostimulants are biodegradable, non-toxic, and compatible with organic agriculture.
Can I use biostimulants along with other agricultural products?
Yes, they are compatible with fertilizers and other organic treatments, as long as recommended dosages and timings are followed.
