The climatic conditions that occur in the coffee regions can influence both the productivity and the quality of the coffees produced. In the agricultural crop 2017/18, the productivity and consequently the volume of coffee produced is in cycle of discharge in the majority of the crops. The quality of coffee now harvested in this harvest is also very good.
Even in regions where coffee is usually fermented in the foot and drinking water / river, this year the quality has improved a lot, as the climate at this time of harvest is proving very dry. With low humidity, the ripe fruits hardly ferment, drying quickly and favoring their quality of drink.
On the other hand, the drought that began to cause water stress very early (already in April and May) and that extends in the main coffee regions of the center-south, already indicates, due to the high defoliation of the plants, a perspective of loss of productivity in the future harvest of 2019. These probable losses due to the climatic effect will be added to those predicted by the dominance of the biennial cycle of low harvest in 2019, considering the cycle of increase occurred in the harvest of 2018.
Also the downward cycle in 2019, which already indicated the greater use of pruning in the post-harvest of 2018 with the use of scaffolding to clear the next harvest, will have the increased use of this type of pruning due to the additional defoliation by stress water.
See the example of water balance in Varginha, which represents, to a large extent, the southern region of Minas Gerais, the main producer of arabica coffee in the country. From July 2017 to June 2018 it rained only 1100 mm, when the normal historical rainfall is 1436 mm annually, therefore 24% less in this last year (see table 1). Now, at the end of July, a water deficit of about 100 mm is accumulating, leaving at least another 2 or 3 normal months of low rainfall, and can accumulate a deficit of 220-300 mm by the end of September or October / 18.
Hence the title of this subject is justified. The climate that facilitates coffee quality tends to reduce productivity in the next crop.
It is still too early to make predictions of likely global losses in the future coffee crop in 2019, but from what has been happening, the least likely reduction over the current crop would be about 10 million fewer sacks. A further reduction will depend on the resumption of rainfall, if late or early, in October / November or in September. For now, the forecasts are sparse and weak rains, which may occur in the coffee region and do not change the situation in the coming months.
Finally it remains to be clarified why we highlight the effect of plant defoliation by stress, either by high load or by water deficit. This is due to the fact that a large part of the coffee reserves, those essential to the flowering glue and to the fruiting of the plants, is concentrated in the remaining foliage in the post-harvest period.