Asturias began producing blueberries in substantial quantities about 15 years ago, called for by the good productive conditions and the growing global demand for this red fruit. Since then, things have changed considerably, due to the appearance of new varieties and cultivation methods that allow their development in areas where it previously seemed unviable. Thus, new countries have joined production and the quality of the fruits has increased. This is a challenge for Asturias, which has to find its market niche to be able to compete effectively with the rest of the territories. The Regional Agri-Food Research and Development Service of the Principality of Asturias (Serida) has just published a report – signed by Juan Carlos García Rubio, Guillermo García González de Lena and Marta Ciordia – in which it proposes several measures to improve competitiveness. Among them, advancing production to the summer months.

Under the heading «New challenges for the expansion of blueberries in Asturias», the report proposes to pose, in the face of this new productive scenario, four challenges: rethinking the most interesting harvest dates; varietal replacement; control of climatic risks and improvement of fruit quality, and minimizing the unproductive period and maximizing productivity.

harvest season

At first, Asturias mainly produced very late harvest varieties, from the months of September and October, which were the ones that provided the best prices. However, the blueberries were not notable for their quality. Currently, there are new production areas such as Peru, Argentina, South Africa or Mexico that put on the market, on the same dates, higher quality fruit and at very competitive prices.

However, in the months of June and July, there is no supply of blueberries in these latitudes, which "would represent one of the best production windows for our region," according to the study.

On the other hand, blueberry production in the Northern Hemisphere in the same months is not high, since in both Morocco and Huelva it usually ends in June. From this date until the end of July "this early summer market niche is much less covered, since the main productions come from central-northern Portugal, northern Spain, Croatia, Serbia, Romania and Georgia mainly, the latter focused "mostly to the Russian market." Even though there are many countries, their production represents less supply than that of countries further north, such as Poland, Ukraine, Germany or Holland, which focus their harvest from mid-July to September.

This favors, then, that the best market prices are reached from end of May to end of July. And to the economic advantage we must add that, in these months, the economic investment can be reduced as the rain cover is not so essential, although it is recommended to cover part of it. And, on the other hand, in these months Drosophila suzukii, an invasive species that appears from August, does not make an appearance.

varietal replacement

Many varieties produced in Asturias have production difficulties and poor quality, due to texture or acidity. It is, therefore, essential to opt for other varieties. Serida considers that There are some with great potential such as those of the Northern Highbush species, "traditionally better adapted to our type of outdoor cultivation", or Southern Highbush, with better quality but more appropriate for protected cultivation.

Climatic risks and fruit quality

According to Serida technicians, we must keep in mind the climatic peculiarities of Asturias, with high relative humidity during spring-summer and frequent rains during the harvest that make the logistics of personnel in outdoor cultivation difficult. To this adverse climate, which causes serious problems, negatively affecting the production and organoleptic quality of the fruit, we must add the presence of the D. Suzukii pest, which, approximately from the halfway point of summer, also negatively affects the success of the crop. Therefore, the need to look for solutions that contribute to minimizing economic losses is evident.

Serida has been recommending to farmers for years that to reduce meteorological risks and address the problem of D. Suzukii cover crops with light structures, as an umbrella, mainly during the harvest period.

An example of the effectiveness of these measures were the 2017 and 2018 campaigns, with heavy and continuous rains, very low temperatures and very few sunny days throughout the spring-summer, in which the few producers who had coverage on their farms They were able to save the harvest. The rest lost almost all their production due to pests and diseases, and what they retained was of very low quality.

Another important issue is that the covers would allow other varieties to be grown in Asturias that have earlier flowering or less tolerance to cold, which have greater productivity and better quality of the fruit: larger size, better texture and more sweetness.

Minimize downtime and maximize productivity

Finally, according to the technicians, "the adjustment and reduction in prices for farmers, together with the increase in all production costs, force agronomic techniques to be optimized to collect the first harvest before the established three years of cultivation."

Today, to achieve good crop development, it is essential to "carry out all soil preparation tasks with the greatest possible precision and rigor, both for the physical part and that which refers to the fertility of the soil", as well as "using the highest possible quality of plant, since the rapid and abundant entry into production will depend on it."

Also, if there is no soil suitable for cultivation, it can be grown on substrate in a container, a technique that is increasingly used worldwide. Although it requires a greater investment per surface area, it is also recovered more quickly.