Zinc & Copper for Olive Trees

Feb. 23, 2026

Zinc, copper, and wood spirit: a perfect trio in the olive grove

The best defense for the olive tree against fungi (peacock eye, leprosy, lead rot) and bacteria (scab) is through the combination of three elements, here's why!

AIPO

Enzo Gambin

Current agronomic and phytosanitary techniques for olive growing are based on the synergy between “processed” zinc and copper , i.e. carried by organic molecules such as acetates and amino acids, and wood distillate .

This combination not only protects the plant's surface, but also allows nutrients to rapidly penetrate the tissues, providing deep nutritional support and effectively combating pathogens from within. This also allows for a significant reduction in copper metallic dosages per hectare, benefiting the ecosystem.

Copper and zinc

Unlike traditional copper, which remains deposited on the leaf and acts exclusively through contact, in new-generation formulations, copper is bound to organic molecules that ensure its complete solubility and penetrating ability . Thus, while traditional copper-based products form an external barrier, these new complexes can penetrate the waxy cuticle of the olive leaf.

Copper penetration also facilitates zinc absorption , allowing it to circulate freely in the plant's lymphatic vessels.
Synergy within the tissues Once inside the plant tissues, an integrated defense strategy is activated ; copper attacks the cell membranes of harmful microorganisms, fungi, and bacteria , through an oxidizing action that disorganizes their structure.
This process creates micro-cracks in the cell membranes, actual biochemical flaws, which compromise their ability to isolate the pathogen from the outside. In practice, copper "disrupts" cellular protections, paving the way for zinc , which can penetrate the cells of the pathogen, as in the case of the scab bacterium, performing a bactericidal action . Therefore, copper, in addition to normally performing its fungicidal function, acts as a zinc activator, implementing actions against fungal and bacterial pathogens with reduced doses of the metal.

The wood distillate

To maximize the effectiveness of these treatments, wood distillate (e.g., BioDea 's ) can be combined with processed copper and zinc. This extract acts as a true catalyst , facilitating the transport of nutrients into the plant and ensuring deeper, longer-lasting protection against pathogens. Once known as "wood vinegar," this extract is rich not only in tannins and polyphenols, but also in acetic acid and acetates. These components perform a fundamental bacteriostatic action , creating an acidic environment hostile to the proliferation of pathogens.

Thanks to this complex composition, the distillate lowers the surface tension of the solution, improving the adhesion and penetration of the copper-zinc complex. Its acidic pH also stabilizes the mixture and optimizes the plant's physiological response to biotic and abiotic stress, making the entire treatment more persistent and effective.

Applications

This combination proves interesting for controlling pathogenic fungi, such as peacock's eye, leprosy, and lead rot .
Copper, in fact, by penetrating tissues, could have a preventative and curative effect.

Similarly, bacteria such as olive leaf spot are counteracted by the combined action of copper and zinc, supported by the action of wood distillate, which optimizes the plant's overall physiological response.

Conclusion

To maximize the effectiveness of this strategy, it is essential to intervene during critical phenological phases, post-pruning, post-harvest, or after adverse weather events, taking advantage of the plant's window of maximum receptivity.