February – restores dormancy in autumn-sown crops and halts the development of some stone fruit species

The cold spell at the end of January, following the unusually high temperatures for the season, restored dormancy in the autumn-sown crops and prevented premature development in some of the stone fruit species.

In February, agrometeorological conditions will be increasingly dynamic. During most days of the first ten-day period they will be determined by below-normal temperatures, but without critical minimum values for overwintering agricultural crops. In most parts of the country, with the exception of the southeastern regions and the Black Sea coast, snowfall, formation of snow cover and an improvement in the conditions for overwintering of the autumn-sown crops are forecast.

At the beginning of the second ten-day period, a warming and a change in the agrometeorological conditions are expected. The forecast temperatures until the end of February in most of the field areas will be close to the climatic norms and will maintain the winter cereal crops in dormancy. Exceptions are again expected in the southern regions and along the Black Sea coast. In these regions, during the second ten-day period, average daily values are forecast to be around and above the biological minimum required for the resumption of vegetative processes in the autumn-sown crops. At the end of February, the wheat stands will be in the third leaf and tillering growth stages.

During the month, the forecast minimum temperatures, in the range of minus 12-13°C, are above the critical thresholds for winter cereal crops that have entered the tillering stage. These values, in conditions without snow cover, will pose a risk to stands overwintering in the third leaf stage (agrometeorological stations: Kneja, Targovishte, Kyustendil, Pazardzhik, Chirpan, Sliven, Yambol, Dolni Chiflik).

The expected precipitation in February, around and above the climatic norms, will increase the soil moisture reserves in the one-meter and two-meter layers. The significant precipitation during the second and third ten-day periods of January, in many places in the country above 60-70 l/m², and in some southern regions – above 120-130 l/m² (Haskovo-165 l/m², Kardzhali-214 l/m², Chirpan-133 l/m², Stara Zagora-144 l/m²), sharply increased the level of moisture reserves in the winter cereal crops. In most of the field areas, the total water reserve in the autumn-sown crops in the one-meter soil layer reached levels above 90% of FC (field capacity).

In February, more suitable conditions for pruning in vineyards and orchards, and for carrying out winter plant protection spraying in orchards, will occur during the second ten-day period. Frequent precipitation during the month will keep the upper soil layers waterlogged, which will hinder the top-dressing of autumn-sown crops with nitrogen mineral fertilizers and the implementation of pre-sowing tillage on areas intended for sowing with early spring crops (peas, vetch, oats, spring barley).

Source: NIMH