The olive harvest marks the beginning of the olive oil production process. The olive grove has been carefully managed throughout the year in preparation for this important agricultural task. The quality of the final product largely depends on proper planning, the timing of the harvest, the harvesting techniques and equipment used, the ripeness of the fruit, and, ultimately, the experience and knowledge of the workers involved. The main objective is to bring together all these factors to obtain the highest possible yield while maintaining the highest quality standards.
What is the optimal time for olive harvesting?
As with other crops, olive harvesting requires a careful assessment of the factors that determine the optimal harvest time. These factors include the type of plantation, olive variety, harvesting methods and techniques, and the stage of fruit ripeness. As the fruit develops, olives gradually increase in size and, from a certain point onward, begin to change color, indicating their stage of maturity. Several factors are taken into account when determining the ideal time for harvesting:
- Oil content in the fruit.
- Changes in the oil's quality as the fruit matures.
- The olive tree's resistance to the mechanical forces applied by harvesting equipment.
- The harvesting dates of the previous season.
The oil content of the fruit increases as the olives mature. The maximum level is reached when all the green olives have disappeared from the tree. However, the organoleptic characteristics of the fruit, and consequently of the oil produced from it, gradually decline as harvesting is delayed. The fruitiest and most aromatic oils are obtained at the beginning of the ripening process, even when a proportion of green olives is still present.
At Las Valdesas, we begin harvesting our olives between late October and early November. As we produce five different varieties of olive oil (Hojiblanca, Arbequina, Picual, Manzanilla, and Frantoio), we stagger the harvest according to the ideal ripeness of each variety. Our oils are early harvest oils, produced with the goal of achieving exceptional fruitiness, outstanding culinary qualities, and the highest possible concentration of polyphenols (natural compounds found in olives with antioxidant and anti-inflammatory properties). Learn more about the polyphenols in our oils.
What are the olive harvesting systems?
The harvesting system used (with varying levels of mechanization) depends on the farm's level of technological development and the type of olive grove plantation. Olive groves can generally be classified as follows:
- Traditional planting: These olive groves have a low density of trees per hectare (between 80 and 120), usually arranged in a square pattern with 10–12 meters between trees. Olive trees often have two or three main trunks to increase production.
- Intensive planting: These olive groves have a density of between 200 and 600 trees per hectare. They consist of single-trunk olive trees planted at spacings of 6 × 6 meters or 6 × 3 meters, with 6-meter working lanes. Harvesting in these plantations is typically carried out using trunk shakers with catch frames or mechanical branch shakers combined with rods and collection nets.
- Super-intensive planting: These plantations have a density of between 1,200 and 2,000 trees per hectare. In this type of olive grove, harvesting operations are fully mechanized.
The harvesting systems, listed from the most traditional to the most advanced, are as follows:
- Hand picking: Workers harvest from the ground or use ladders, running their hands along the fruit-bearing branches and allowing the olives to fall onto nets previously spread beneath the trees. Harvesting costs are very high with this method because it is labor-intensive and has a relatively low harvesting rate.
- Beating with poles: Workers use poles between one and four meters long to strike the olive branches. The blows are applied sideways to the areas where the olives are located, minimizing damage to the tree, as excessive damage could affect the following year's production. As with the previous method, the olives fall onto nets placed beneath the trees and are then transferred to transport containers for delivery to the olive mill.
- Tree shaking: This technique involves using either a tractor-mounted mechanical arm or a handheld device to shake the tree or its branches until the olives fall due to the vibration. The olives are collected on nets placed beneath the tree. When using a tractor-mounted shaker, the machine is attached to the trunk of the olive tree; when operated manually, it is attached to the branches. The latest development in this harvesting method is the use of machines known as "buggies," which also use vibration but offer greater maneuverability between the rows of trees.
What are the stages of olive harvesting?
The olive harvesting process for olive oil production can be divided into the following stages:
- Soil preparation. This includes clearing the area to facilitate the collection of olives, as well as adapting the planting layout so that the rows are wide enough to allow harvesting equipment to move easily.
- Fruit collection. Olives can be harvested directly from the tree ("tree-harvested olives") using one of the techniques described above, or collected from the ground after naturally falling from the tree as they ripen. Naturally, olives collected from the ground are more mature than those harvested directly from the tree and, consequently, produce lower-quality oil.
- Transport. When olives are collected on nets placed beneath the trees, it is essential to remove leaves, branches, and other plant debris both in the field and later at the olive mill. The time between harvesting and milling the olives should be kept as short as possible, and the transportation method should minimize any potential damage to the fruit.