Dynamic weather with frequent precipitation in March

The above-normal seasonal temperatures during the second half of February resumed the vegetation of a large part of the overwintering agricultural crops.

During the first ten-day period of March, agrometeorological conditions will again be determined by above-normal temperatures. The forecast warm weather at the beginning of the month, with maximum temperatures up to 18-19°C, will activate vegetative processes in autumn-sown crops and fruit trees in the lowland regions of the country. The expected precipitation during the ten-day period will improve soil moisture reserves in the fifty-centimetre soil layer and the conditions for the development of winter cereal crops and winter rapeseed. During this period, a significant part of the wheat stands, which have overwintered at the third leaf stage, will enter the tillering stage. In rapeseed, the rosette stage will predominate.

During the second ten-day period, the forecast temperatures, around and slightly below the climatic norms, will limit the development of agricultural crops. In some places in Northern Bulgaria and in the western regions, where precipitation in the form of snow is not excluded, a weakening and short-term cessation of vegetation in autumn-sown crops will be observed. In the remaining regions of the country, the values of the mean daily temperatures will be close to the biological minimum required for the development of winter cereal crops and winter rapeseed. 

During the third ten-day period of March, an improvement in thermal conditions and activation of vegetative processes in autumn-sown crops is expected. At the end of the month, the tillering stage will predominate in wheat. In winter cereal crops sown within the optimal agrotechnical period, an increase in the tillering coefficient will be observed.

In March, the following phenological stages will take place in fruit crops: swelling and bud burst of fruit buds, and at the end of the third ten-day period, in stone fruit species (almond, apricot, peach) in the lowland regions, bud formation and flowering will be observed. The forecast minimum temperatures during the month, down to minus 8°C, will pose a risk to the fruit crops that are advanced in their development and have entered the stages of bud formation and flowering.

The precipitation in February, following the prolonged winter drought, contributed to overcoming the moisture deficit in winter cereal crops in the upper soil layers. The expected precipitation in March, around and above the norm, will increase soil moisture reserves in the one-metre soil layer.

On most days in March, the forecast dynamic weather, with frequent precipitation, will impede the implementation of some seasonal agrotechnical activities. More favourable conditions for carrying out pre-bloom plant protection spraying in orchards, and for pre-sowing tillage of areas designated for early and medium-early spring crops, will occur at the beginning of the month and during most days of the third ten-day period. In mid-March, the agrotechnical window (15-20.03) for sowing sunflower in Southern Bulgaria begins, and in the middle of the third ten-day period (25.03–5.04) – in the Danube Plain.

Source: NIMH