Cold damage: the hidden challenge for avocados

In agriculture, one season rarely behaves exactly like the previous one, and 2026 is no exception. We had just come from a mild winter followed by a warm autumn that prolonged fruit and foliage growth, maintaining high temperatures between March and May that boosted late bud break in the trees. However, the scenario changed abruptly with the arrival of a June of persistently low temperatures that generated considerable stress in the orchards.

Given this situation, it is crucial to make a technical distinction: not all the damage observed this season can be directly attributed to frost; we must begin to speak firmly of chilling injury. Frost leaves obvious signs such as scorched foliage, loss of flower buds, damaged peduncles, and fruit drop—situations for which many exposed orchards already have micro-sprinkler control systems. This season, however, has presented cumulative stress from consecutive days of low temperatures that cooled the soil and directly affected the root system.

Accumulated stress that impacts the Dusa pattern

One of the first symptoms of this phenomenon has been the drop of apparently healthy fruit, with intact peduncles and no typical sunburn. This behavior has been particularly pronounced in orchards established on the clonal rootstock Dusa. While Dusa is known for its vigor, root development, and ability to produce good-sized fruit, it has shown sensitivity to prolonged periods of cold in certain areas for years, a response previously observed in the O'Higgins Region (even above 200 meters above sea level) and now manifesting in the Valparaíso Region.

Regarding the impact on production, the reality observed in the field is heterogeneous. Although the industry reports localized losses of between 20% and 30% of the fruit, the disparity between orchards—some planted with Dusa rootstocks with no losses and others with rootstocks planted with low-impact seedings—necessitates an analysis of agronomic management. Excessively vigorous trees, those with nitrogen overload, or those with nutritional imbalances and different biostimulation strategies respond differently to the same stress event, so it is still too early to define the overall extent of the damage.

Hidden damage: post-harvest and floral differentiation

Fruit drop is only the most visible effect. The main concern lies in the indirect damage that has not yet manifested itself:

On one hand, we have post-harvest and ripening ; the stress accumulated in the embryo can accelerate the ripening process, causing an early color change in the fruit that remains on the tree. This affects its ability to withstand long journeys to distant markets and reduces its shelf life.

When it comes to flower differentiation, prolonged cold can disrupt bud development. A bud that appears to be a flower bud may transform into a vegetative shoot, develop a weak panicle, or lose buds before flowering, thus impacting next season's production.

Root reactivation and strategic nutrition

Since the roots remained in cold, saturated soils for weeks, their reactivation at the start of the new growth cycle will be slower. Therefore, the agronomic recommendation for this season is to avoid aggressive immediate fertilization programs and prioritize root biostimulation through the use of amino acids, seaweed extracts, chitosan, and organic matter.

In addition, foliar nutrition will play a key role in directly supporting flowering. In this area, the technological evolution of agricultural drones—with greater power and penetration capacity than equipment from a decade ago—now offers a technically viable alternative for these applications.

Market outlook in the face of a complex scenario

The coming weeks will be crucial for assessing the condition of the fruit on the trees and the flowering response. Despite the agronomic complexity, the avocado market is showing clear signs of stability. The emergence of new exporting companies linked to other sectors (such as cherries, citrus fruits, and table grapes) reflects a constantly expanding international demand, driven by growth in Europe, the importance of Argentina, and the strength of the Chilean domestic market.

Understanding the difference between the visible impact of a frost and the slower developmental story that cold damage tells will be key to adjusting the technical management of orchards and safeguarding the competitiveness of the industry.