Agrometeorological forecast for the month of April

During the month, an increased probability of frost formation is forecast for the second ten-day period, which should be taken into account when hardening vegetable and tobacco seedlings. At the end of the second and the beginning of the third ten-day period in the field areas, soil temperatures in the 10 cm layer will reach suitable values for sowing grain maize, and at the end of the month – also for the heat-loving spring crops (cotton, beans, peanuts, watermelons, melons). In April, the high atmospheric humidity and frequent showers will maintain favourable conditions for the development of a number of fungal diseases

After the wet weather at the beginning of spring, an improvement in the conditions for carrying out the seasonal agrotechnical activities is expected during the first ten-day period of April.  The precipitation in March, which in many parts of the country exceeded the monthly norms twofold (Vidin - 135 l/m², Vratsa - 112 l/m², Lom - 119 l/m², Kneja - 104 l/m², Svishtov - 104 l/m², Shumen - 101 l/m², Dragoman - 105 l/m², Blagoevgrad - 102 l/m², Haskovo - 104 l/m², Kardzhali - 114 l/m², Elhovo - 122 l/m², Sliven - 103 l/m², Karnobat - 118 l/m²), led to waterlogging of the soil in the 50 and 100 cm layers and serious delays in carrying out the pre-sowing tillage and the sowing of early and medium-early spring crops. For these reasons, in Southern Bulgaria the agrotechnical deadlines for sunflower sowing, which fall in the second half of March, have been missed. For Northern Bulgaria these deadlines are in the first ten-day period of April. During the first ten-day period the forecast above-normal temperatures will accelerate the vegetation of the autumn-sown crops. During this period a large part of the wheat and barley in the field areas will enter the stem elongation phase. In rapeseed the budding phase will be observed.

On most days of the second and third ten-day periods, the development of agricultural crops will proceed at moderate rates, at temperatures close to the climatic norms. In the second half of April, the flowering phase in rapeseed will take place. In the third ten-day period, the wheat and barley that entered stem elongation earliest, in mid-March (Plovdiv, Pazardzhik), will enter the heading phase, and in some places in the southern regions the flowering phase of the crops will also be observed.

The expected precipitation in April, around the monthly norm, will maintain soil moisture reserves within optimal limits for the vegetation of the autumn-sown crops and the sown spring crops.

During the month, an increased probability of frost formation is forecast for the second ten-day period, which should be taken into account when hardening vegetable and tobacco seedlings.

At the end of the second and the beginning of the third ten-day period in the field areas, soil temperatures in the 10 cm layer will reach suitable values for sowing grain maize, and at the end of the month – also for the heat-loving spring crops (cotton, beans, peanuts, watermelons, melons).

In April, the high atmospheric humidity and frequent showers will maintain favourable conditions for the development of a number of fungal diseases – septorioses in winter cereal crops; in fruit trees – blossom blight (early brown rot), scab, shot hole disease. More suitable conditions for conducting plant protection spraying will occur on most days of the first, at the beginning and at the end of the second ten-day period.

Source: NIMH