Taking the Mystery Out of Biostimulants

They’re not fertilizer and they’re not pesticides. But what are they? Biostimulants are their own class of agronomy products that have been kept in the shadows for too long.

4 mins
Dr. Eduardo Cancellier
ICL Global Biostimulants Specialist Agronomist

Biostimulants have a sense of mystery about them. I’ve even heard scientists say we don’t really understand how they work.

That’s only partially true. Because the category of biostimulants includes a wide range of products, they work in a variety of ways and have varying effects on different crops. Even though there are many products we understand thoroughly, science is so fast paced that we also continually discover new substances and are learning how they work.

New Frontiers

At ICL, we are committed to sustainable agriculture practices and we believe biostimulants are an innovative solution to help us grow better plants while using fewer resources. I work with agronomists and growers around the globe to decode the mystery of how biostimulants affect different crops in various conditions.

The challenge is that while our knowledge of soil and plant nutrients is quite advanced, with over 150 years of use and research in comparison, our understanding of biostimulants is quite recent and not widely spread in the agronomy community yet.

What are biostimulants?

Let’s start with what they are not – biostimulants are not fertilizers and they are not pesticides. Biostimulant products include a diverse group of substances that improve plant growth and performance. They do not provide nutrients directly, but they do help plants access and utilize nutrients in their environment.

We could compare fertilizer to the food humans eat to glean nutrients. Food is essential – but there are also several other factors – such as sleep, fitness, stress, and supplements – that affect how the body is able to absorb and use nutrition. Biostimulants are like the vitamins or probiotics a person might take as one way to improve their overall health.

Each biostimulant works in its own particular way – improving nutrient use efficiency, a plant’s environmental stress tolerance, crop quality, and even beneficial microbial activity. For instance, ICL’s BIOZ® Diamond contains natural organic substances that, when they come in contact with a plant’s roots, change how the roots work physiologically. The effect is similar to the way the plant hormone auxin induces root growth. The substance will also activate the enzymes that transport nutrients inside the plant so they start working faster.

Solving a Modern Problem

What do biostimulants do?

Through years of research, we know exactly what nutrients plants need, enabling us to develop several types of fertilizer technologies to deliver the optimum form of nutrition. But there is a second step. Once the elements are in the soil, the plant has to reach the nutrients, and it needs the capacity to uptake them.

That’s where biostimulants come in. Biostimulants can cause roots to grow deeper and stronger, allowing the plant to more efficiently explore the soil. To put it in economic terms, farmers invest to build soil fertility, and biostimulants allow plants to access that bank account in the soil.

Biostimulants play another important role because most modern crop varieties have been bred to grow fast to maximize yield. In doing so, it has reduced the capacity of plants to explore deeper with their roots and take up all the nearby, but just out-of-reach, nutrients. By activating processes within the plant, biostimulants can increase the transport of nutrients to a growing crop.

Crops can experience many types of stress due to what we call abiotic factors – soil salinity, drought, high temperatures, etc. Biostimulants can improve the natural capacity of plants to cope with those stressors. While biostimulants are not pesticides and none of them have the goal to kill any pest or disease, by improving the natural capacity of plants, they become more resistant to diseases.

Moving from Confusion to Clarity

Are biostimulants regulated?

Adding to the confusion about biostimulants is that they are defined differently around the world. Some regulatory bodies define biostimulants as microbials, but others do not. I like to note that the law of nature does not care about the law of man. Biostimulants work the same no matter how they are labeled or regulated.

Because regulatory barriers in the biostimulant market are not as strong as for other types of agricultural inputs, some less-than-reputable companies have brought products to market in the past that have not been extensively studied or proven. Marketers have also made exaggerated claims, which has caused a lot of growers to be skeptical about biostimulants.

Today, extensive scientific literature provides strong evidence of how and why these products work. If you’re considering using a new product, be sure to pressure test the information. Minimally, ask your agronomist to show you the field trials or data sheets that validate the results in soil types and crops most relevant to those you’re working with. Look for products with a proven track record.  While BIOZ® Diamond is new on the U.S. market this year, it has been used in Brazil for more than 20 years with success, primarily on soybeans, fruits, and vegetables. U.S. trials show that it has consistently increased corn and soybean yields.

As we learn more, we are decoding the mystery of biostimulants and understanding how they are an important tool to help farmers grow valuable fruits, vegetables and grain more sustainably.