In a scenario where the industry of blueberry Seeking to improve fruit firmness, quality, and condition, plant nutrition continues to occupy a central place within the technical management of the crop. This was the view expressed by Juan Hirzel, a researcher at the Agricultural Research Institute (INIA) of Chile and an international consultant, who emphasized the need to understand nutrition as a balanced system, rather than simply prioritizing certain elements.

During his participation in the XXXIX International Blueberry Seminar in Lima, Hirzel addressed the role of different nutrients in cultivation, warning about the importance of not overdoing calcium and also highlighting the contribution of silicon, especially in firmness and post-harvest.

From a nutritional point of view, what role does calcium play in blueberries?

Calcium is an important element, but it's not the most important. All nutrients are essential in the right amounts. Excessive amounts of one can negatively impact another; a deficiency also affects growth. Just like humans, plants have a diet, and management should respond to their needs, not to over-application.

What factors determine the absorption of calcium by the plant?

Primarily, the environment where the plant is growing—the soil or substrate, the health of the roots, and their ability to absorb water, oxygen, and nutrients—all of these factors modulate how much calcium the plant can consume.

Does the source of calcium influence its effectiveness?

Yes. There are different sources, such as salts or organic molecules. Studies show that when calcium is associated with organic molecules, such as carboxylic acids or lignosulfonates, there is greater absorption and a slight increase in its movement into the fruit, which can improve firmness.

Juan Hirzel at the XXXIX International Blueberries Seminar Lima 2026. © Blueberries Consulting

In terms of strength, what role does silicon play?

Silicon is a beneficial element. When applied as a foliar spray, it is incorporated into the tissues and located under the fruit's cuticle. This increases mechanical resistance, that is, firmness.

Does it have other effects besides firmness?

Yes. It also reduces fruit dehydration, which improves post-harvest life. So there's a double effect: greater firmness and better storage performance.

Is it advisable to apply silicon to the soil?

It doesn't make much sense. Agricultural soils already contain silicon in various forms, and its release depends on biological factors and pH. To have an effect on the fruit, the application must be foliar.

What is the most effective time to apply silicon?

Increasing the frequency of applications close to the start of harvest or during harvest has shown improvements in firmness and fruit quality.

Juan Hirzel at the XXXIX International Blueberries Seminar Lima 2026. © Blueberries Consulting

A nutritional perspective

Hirzel's approach provides a more accurate understanding of nutrition. blueberryThis shifts the focus away from single-nutrient approaches and towards a logic of physiological balance. In a sensitive crop like this, both deficiency and excess can negatively impact yield.

In parallel, the evidence presented on silicon shows how the industry continues to incorporate complementary tools to strengthen key attributes such as firmness and post-harvest life, especially in markets where distance and transit time impose greater demands.

Thus, nutrition ceases to be understood merely as a list of applications and comes to be seen as a system where plant, environment, and management interact. In this scenario, it is not only important what to apply, but also how much, how, and when to apply it.

Juan Hirzel at the XXXIX International Blueberries Seminar Lima 2026. © Blueberries Consulting

Participation in Lima 2026

Juan Hirzel participated in the XXXIX International Blueberries Seminar Lima 2026 in two sessions of the technical program. In the main hall, he presented the talk “Variety-Directed Nutrition: Redefining Sufficiency Ranges for New Genetics of blueberries”, while in the complementary hall he led the “Workshop on interpretation and data analysis”.

Both interventions reinforced the same line of work for the industry: in the cultivation of blueberryNutrition cannot be approached from general recipes or isolated nutrients, but from technical criteria capable of integrating variety, diagnosis and productive decision-making.

Read also:

The voices that drive the blueberry industry today are focusing on its new challenges

From data to decision: the workshops by Claudia Moggia and Juan Hirzel that organized criteria for Lima 2026

International Blueberry Seminars 2026: Blueberries travel through Peru, Chile, Mexico, Morocco and China

Check out the full interview on our YouTube channel, Blueberries TV