Critical temperatures for early-flowering stone fruit species

The late winter weather events at the end of the first and the beginning of the second ten-day period of March terminated the vegetation processes of the autumn-sown crops in a large part of the field regions of the country and put to a serious test the fruit crops that are more advanced in their development. In some places in the Danube Plain and in the southern regions (Plovdiv, Stara Zagora, Chirpan) minimum temperatures down to minus 6-7°C have been recorded, which are critical for some of the fruit trees that have entered the budding and flowering stages – almond, apricot and peach.

In the second half of March negative minimum temperatures are forecast and an increased risk of damage to early-flowering stone fruit species.

Until the end of the second ten-day period the agrometeorological conditions will be highly dynamic. After the brief warming and snowmelt in mid-March, below-normal temperatures are forecast for the second half of the period, which will restrain the development of agricultural crops. Exceptions are expected in the far southern regions, where the average daily temperatures will reach and exceed the biological minimum required for the vegetation of winter cereal crops. At the end of winter, the wheat stands will be predominantly in the tillering stage.

During the next period significant precipitation is expected and an increase in soil moisture reserves in the 100 cm layer. In most of the field regions, for the winter cereal crops, they will reach levels above 90% of the field capacity (FC).

During the period the conditions will be unsuitable for carrying out seasonal soil tillage and for sowing of early and medium-early spring crops. The probability is high that the agrotechnical deadlines for sunflower sowing in Southern Bulgaria, which start in mid-March, will be missed.

Source: NIMH