Agrometeorological forecast for August

On most days of the first ten-day period of August, agrometeorological conditions will be determined by unsettled weather and temperatures around and slightly below the norm for the period. The forecast meteorological conditions at the beginning of the month will increase the level of infections from certain fungal pathogens: blights on vegetable crops from late field production, late brown rot in orchards, and grey mould on the ripening early grape varieties.

The rainfall at the end of July, which in places in the northwestern and central regions exceeded 30-40 l/m² (N. Selo, Vidin, Vratsa, Montana, Lovech, V. Tarnovo), and the precipitation expected during the first ten-day period of August, will have a beneficial effect on the second crops and on the later maize hybrids, in which grain formation and filling will take place. During the ten-day period, the medium-early maize hybrids will be in the milk maturity stage, while the early hybrids will reach wax and full maturity (agrometeorological stations Bazovets, Kneja, Glavinitsa, Pazardzhik, Plovdiv). In sunflower, in the Danube Plain and in the southern regions, the ripening stage will occur.

At the end of the first ten-day period, a substantial increase in temperatures is forecast and an accelerated progression of the final stages of development of the late field crops. During the second and third ten-day periods, agrometeorological conditions will be determined by relatively dry weather and temperatures around and above the climatic norms.

During the second half of August, a large part of the late field crops will complete their development. In sunflower, mass technical maturity will be observed, and in soybean – the ripening stage. At the end of the month, wax maturity will prevail in the medium-late maize hybrids. In rice, the milk maturity stage will occur, and in cotton – the opening of the bolls.

During the second half of the month, the deficit of soil moisture in the second crops will deepen and will necessitate increased irrigation rates. In many places in the field regions, the lack of moisture in the upper soil layers will hinder the quality performance of deep ploughing and pre-sowing tillage of the areas designated for sowing winter oilseed rape. The agrotechnical sowing periods for oilseed rape begin in the third ten-day period of August.

In August, for late fruit tree varieties, the harmful activity of the last generation of fruit moths should not be underestimated. The relatively dry weather during most days of the month will be a precondition for an increase in mite populations. In vineyards, it is necessary to monitor the occurrence and density of the third generation larvae of the European grapevine moth. Plant protection spraying should be carried out during the cooler hours of the day with products having an appropriate pre-harvest interval, in accordance with the ripening period of the crops.

Source: NIMH