Table olive yield and quality in super-high-density hedgerows: a long-term study

Olive cultivation in super-high-density orchards has expanded worldwide in olive groves for oil production, reducing cultivation costs and facilitating integral harvesting. Commercial expansion for table olive production is much more recent, but receives special attention given the increasingly scarce labor force. This study presents, for the first time, a long-term evaluation of olive production and quality in super-high-density hedgerows (3.75 m x 1.35 m) of two traditional cultivars, 'Manzanilla de Sevilla' and 'Manzanilla Cacereña'.

The hedgerows were grown under irrigation and identical environmental Mediterranean conditions; they were monitored for nine years from the fifth year after planting (2012-2020). Specifically, for each cultivar and year, olive yield, fruit quality, mechanical harvesting efficiency and dimensions of the hedgerows were studied. Besides, the growing habits of both cultivars were analyzed over three years and compared to those of adjacent 'Arbequina' hedgerows grown under similar conditions. This is a low vigor cultivar typically grown for oil production.

The results demonstrate that both the Manzanilla de Sevilla and Manzanilla Cacereña cultivars formed continuous and more vigorous than 'Arbequina'. 'Manzanilla Cacereña' experiences a more restricted growth. This results in a narrower and shorter canopy that is significantly more productive and efficient, achieving a mean value of 15 t ha^-1 and a cumulative yield of 136 t ha^-1, 65% higher than that of 'Manzanilla de Sevilla' (89 t ha^-1 cumulative yield; 10 t ha^-1 mean). The efficiency of fruit removal exceeds 96% for both cultivars, but while 'Manzanilla de Sevilla' produces larger fruit with greater commercial value, it is extremely susceptible to mechanical damage-specifically browning and cuts-during harvesting. In contrast, 'Manzanilla Cacereña' stands out for its physical integrity, maintaining high fruit quality after mechanized harvesting.