We will analyze the different reasons why olives wrinkle on tree, drought, frost, olive pests, diseases, nutritional deficiencies, fat yield…
Finding wrinkled olives in the olive tree is something that can raise our concern.
Influence of drought on olive wrinkles
The olive tree is a tree very drought tolerant. In times of maximum water shortage, the olive tree closes the stomata of the leaves and begins to extract the water stored in the olives to survive. As a consequence, the olives are wrinkled. This is common in weakened trees or when rains are delayed and the olive tree has an important load.
This wrinkled olive is usually reversible with rain. Crumpled olives ripen before and can produce EVOO of good quality.
When the olive tree fertilizer is not adequate or the soil blocks the absorption of nutrients.
If water is scarce and there is Potassium deficiency, the olive tree often has difficulties in removing the water it needs from the ground. Because of this, olives wrinkle more easily.
Subsequently, in the winter, olives of olive trees with deficiencies wrinkle more easily.
In cases of deficiencies of Potassium or other minerals, the foliar fertilizer applications are very useful for the farmer.
Pests and diseases of the olive tree
Some olive pests and diseases can affect olives and produce wrinkles. For example, the olive tree borer, which drills the peduncle, wrinkling and irreversibly drying the olives.
The fungi that cause soapy olives, olive leprosy and rot sphaeropsis dalmatica can mummify infected olives.
Are olives wrinkled on tree with frost?
Frost can wrinkle olives considerably, this is due to two situations.
On the one hand, the olive tree enters a vegetative stop by lowering the average temperature of 10 ° C, so it stops pumping sap to the olives. On the other hand, the cold and dry air at night, favors the evaporation of the water contained in the olives that have been heated by the day. This wrinkle can be reversible when the olives have not frozen, temperatures soften and it rains abundantly.
When olives are wrinkled on tree by frost, the olive oil quality may be compromised. When the olives freeze, they begin to deteriorate, the fruits are lost and olive oil defects appear.
For this reason, in areas where there is a risk of frost, the olives harvest must be started before ripening. With the arrival of low temperatures, the olive tree cannot produce oil and we risk losing quality.
Influence of the variety on the olives shrivelling on tree
Naturally, varieties of olives with high fat yield are less sensitive to shrivel up. This is because the proportion of dry matter in the fruit is greater.
For example, in my area the variety Manzanilla Cacereña wrinkles easily, instead Verdial de Badajoz and Cornicabradon’t wrinkle easily.
We have translated the information on our website from Spanish to English. Note that some words may have seen their meaning altered during their translation.