Alternate Bearing in the Olive Grove: How to Avoid it With a Proper Nutrition

Alternate bearing is a common phenomenon in olive groves that can have a great impact on olive oil production. When we talk about alternate bearing, we refer to the alternation of fruit load from one year to another, which means that one year the olive grove produces a large amount of olives and the next year it produces very few. This cycle is detrimental to olive growers, as it affects the production stability and eventually the economic returns. However, a proper nutrition can help minimize the alternate bearing and promote a more stable production. 

Alternate bearing is a natural phenomenon that occurs in many species of fruit trees, including olive trees. The reason behind alternate bearing in olive trees is a combination of genetic and environmental factors. One year, the olive tree produces an excessive load of fruit, depleting its energy and nutrient reserves, and resulting in low production the following year.

The role of nutrition in alternate bearing 

Poor nutrition is a key factor in alternate bearing in olives groves. When olive trees do not receive the right nutrients, they cannot develop and maintain enough flower buds for the next fruiting season. In addition, the lack of nutrients weakens the overall health of the tree, making it more vulnerable to disease and stress. This is why alternate bearing can be prevented with the right nutrition.

1. Soil and leaf analysis: Before implementing any fertilization strategy, it is essential to conduct soil and leaf analyses to determine nutritional deficiencies. These analyses will provide valuable information on required nutrients and appropriate application rates.
2. Balanced fertilization: Use balanced fertilizers containing the essential nutrients that olive trees need, such as nitrogen, phosphorus, potassium and micronutrients. The application of these nutrients should be based on soil and leaf analysis recommendations.
3. Nutrition throughout the year: Provide nutrients throughout the year, rather than concentrating fertilization at one time. This will help maintain the health of the olive trees throughout the growth cycle.
4. Efficient irrigation: Ensure a proper irrigation to avoid water stress situations that can worsen the alternate bearing. Deficient irrigation can lead to greater alternation in production.
5. Shaping and renewal pruning: Carry out appropriate pruning to promote the development of flower buds and remove unproductive wood.

In the late autumn period, it is essential to remember that our crop enters a stress and exhaustion phase due to the harvesting season. To address this challenge, we consider two essential practices.

• Post-harvest potassium fertilization: During the post-harvest season in the olive grove, it is advisable to apply potassium as a fertilizer. Potassium strengthens the resistance of olive trees to abiotic stress such as water stress, cold and heat. After harvest, olive trees often face adverse conditions, and an proper supply of potassium can strengthen their ability to resist and recover quickly.

We recommend the use of Hero K 40 Denso Neutro, a highly concentrated potassium fertilizer with a neutral pH. Its Denso technology has been designed to improve adherence and persistence in the crop, increasing nutrient uptake, translocation and metabolization.

• Prevention of fungal and bacterial diseases: With increased humidity and mild temperatures during autumn, it is essential to prevent and control diseases that can affect olive trees. Some of these diseases include olive knot (Pseudomonas savastanoi) and anthracnose (Colletotrichum spp.), among others. Copper proved to be an effective ally in reducing both diseases and latent infections in olive trees. Even if no disease symptoms are observed in autumn, pathogen spores may still be present on leaves or other plant tissues.

The treatment with Herocuper 70/38, which also uses Denso technology, can prevent the development of these latent infections during the winter and spring, thus contributing to the health of the olive trees.

In addition, it is important to consider that alternate bearing in olive groves can have a negative impact on olive oil production. However, with a proper nutrition and management of the olive grove, it is possible to minimize this phenomenon. Soil and leaf analysis, balanced fertilization, efficient irrigation and pruning practices are essential tools that ensure more consistent production and maintain the long-term health of olive trees. This investment in the proper nutrition of the olive grove not only benefits growers, but also contributes to the welfare of the olive oil industry overall.