Weather and harvest conditions aren’t the only things that can affect the quality of olives grown for olive oil. Another important factor that farmers must consider to deliver the best possible crop is the soil.
The type of soil used to grow olive trees has the power to influence the quality and flavor of the fruit. In fact, two olives of the same variety can be grown under the same conditions but with different soil, and the result will be olives with different characteristics. Bertolli collaborates closely with farmers to ensure that all the olives used in their oils are grown in high-quality soil and that the vegetal ground cover — plants that protect the soil — is preserved to ensure a healthy growing environment for the trees.
Delivering the right amount of water
Olive trees are naturally from non-irrigated lands, so they don’t require a lot of water. In the summer, the vegetal cover helps protect and maintain the soil’s moisture under the hot sun. At times, during an especially warm and drought-ridden season, farmers may deem it necessary to water the trees.
Rafael Sicilia, a farmer in the Andalucía area who specialized in growing Hojiblanca and Picudo olive varieties, shares that there is a delicate balance when it comes to the amount of water needed for growing the perfect fruit. “The olive tree is a dry land tree, and some farmers will provide irrigation to the trees in order to increase olive production.” But, he counters, the olives harvested in these conditions will have a lower fat content, so less oil will be pressed from the fruit.
Considering land elevation
In addition to water access, olive orchard growers must adapt their farming techniques to their geographical factors, such as an area’s land elevation. For example, if a grove is sitting on flat land, the soil is deeper and able to allow the tree to produce more fruit.
Juan Caballero, Executive President of Cooperativa Olivarera de Los Pedroches in Andalucía, Spain, has olive groves positioned on a hill where the soil is shallow. The slope allows water to easily travel through the groves. To retain water and fight erosion, farmers use natural systems, like letting plants naturally grow on the land, and organic materials, such as manure. “Deeper soils will result in bigger productions,” explains Caballero. “But this doesn’t mean that the quality is better or worse — it just affects the yield.”
After 33 years in the industry, Caballero strongly believes that it’s important to maintain the land’s natural vegetal ecosystem. The vegetal cover provides security for the olive trees and also helps preserve biodiversity. It’s important for farmers to consider biodiversity, as it protects the natural ecosystem of an environment, where each plant and animal species plays a role. “We promote the growth of local plants, such as clover, but at the same time, we want to make sure many different plants can grow in the region,” says Caballero.
A common technique for maintaining nutrient-rich soil happens after the harvest. Sicilia and Rafael Luque, who manage more than 120 acres, both trim their olive tree branches, crush them and then spread them into the soil. This method brings the olive grove ecosystem full circle.
Through close monitoring of water retention and biodiversity, farmers are able to cultivate the growth of strong olive trees that can last for centuries. In turn, these resilient trees bear the fruit that lives up to Bertolli’s standards. By maintaining nutrient-rich soil, farmers are able to consistently produce the high-quality extra virgin olive oil consumers have come to expect.