Agrometeorological forecast for the month of June

On most days in June, agrometeorological conditions will be determined by unstable weather with unevenly distributed precipitation, which will also result in substantial differences in soil moisture reserve levels. In Western Bulgaria, where June precipitation, similarly to that in May, is expected to reach and exceed the monthly norms, very good soil moisture reserves are forecast. For spring crops, in the 50 and 100 cm layer they will remain above 80% of field capacity (FC). Lower levels of soil moisture reserves are expected in the eastern regions, where less precipitation is forecast in June as well.

During the first and second ten-day periods, the development of agricultural crops will proceed at a moderate rate, under temperatures close to the climatic norms. At the beginning of June, in the higher fields, grain filling will be taking place in the winter cereal crops. In wheat in the lowland areas, the milk ripeness stage will be observed, while in barley – milk ripeness and transition to wax ripeness. In wheat, during the interphase period grain filling – milk ripeness, the larvae of the sunn pest (Eurygaster integriceps) cause serious damage. During this period, wheat stands must be inspected for the presence of the pest and, at densities exceeding the economic injury threshold (2 larvae/m²), insecticidal treatment is imperative.

At the end of the first and the beginning of the second ten-day period, barley will predominantly be at wax ripeness, and rapeseed will be in the ripening stage.

During the third ten-day period, the development of agricultural crops will proceed at an accelerated rate, under above-normal thermal conditions. In the first half of this ten-day period, wheat in the lowland areas will reach wax and full ripeness. By the end of June, some of the spring crops will enter reproductive development stages – in sunflower, the onset of flowering will occur, and in early maize hybrids – tasseling and flowering of the tassel.

During the month, the forecast maximum temperatures, in places up to 35°C, will have a negative impact on flowering and fertilization in vegetable crops. The meteorological conditions in June will maintain an elevated infectious background of fungal pathogens: late brown rot in later cherry cultivars, scab and powdery mildew in fruit trees, downy mildews in vineyards and vegetable crops. In grapevine, the interphase period from flowering of the inflorescences to the formation of pea-sized berries is critical for downy mildew infection. During the first ten-day period of June, an increased probability of hail is forecast, with a risk of lodging of crops and additional damage to agricultural crops. After a hailstorm, the affected fruit and vegetable crops must be treated with copper-containing fungicides at the first opportunity.

During the month, more suitable conditions for conducting in-vegetation soil tillage for spring crops will occur in the third ten-day period.

Source: NIMH