  It is customary, when writing of any crop culture, to give precedence to site and soil, but in the case of cacao these considerations are of secondary importance, and while none of the minor operations of planting, pruning, cultivation, and fertilizing may be overlooked, they are all outweighed by the single essential—climate. In general, a state of atmospheric saturation keeps pace with heavy rainfall, and for that reason we may successfully look for the highest relative humidity upon the eastern shores of the Archipelago, where the rainfall is more uniformly distributed over the whole year, than upon the west. There are places where the conditions are so peculiar as to challenge especial inquiry. We find on the peninsula of Zamboanga a recorded annual mean rainfall of only 888 mm., and yet cacao (unirrigated) exhibits exceptional thrift and vigor. It is true that this rain is so evenly distributed throughout the year that every drop becomes available, yet the total rainfall is insufficient to account for the very evident and abundant atmospheric humidity indicated by the prosperous conditions of the cacao plantations. The explanation of this phenomenon, as made to me by the Rev. Father AlguÉ, of the Observatory of Manila, is to the effect that strong equatorial ocean currents constantly prevail against southern Mindanao, and that their influence extend north nearly to the tenth degree of latitude. These currents, carrying their moisture-laden atmosphere, would naturally affect the whole of this narrow neck of land and influence as well some of the western coast of Mindanao, and probably place it upon the same favored hygrometric plane as the eastern coast, where the rainfall in some localities amounts to 4 meters a year. While 2,000 mm. of mean annual rainfall equably distributed is ample to achieve complete success, it seems almost impossible to injure cacao by excessive precipitation. It has been known to successfully tide over inundation of the whole stem up to the first branches for a period covering nearly a month. Irrigation must be resorted to in cases of deficient or unevenly distributed rainfall, and irrigation is always advantageous whenever there is suspension of rain for a period of more than fifteen days. Concerning temperatures the best is that with an annual mean of 26° to 28°, with 20° as the mean minimum where any measure of success may be expected. A mean temperature of over 30° is prejudicial to cacao growing. The last but not least important of the atmospheric phenomena for our consideration are the winds. Cacao loves to “steam and swelter in its own atmosphere” and high winds are inimical, and even refreshing breezes are incompatible, with the greatest success. As there are but few large areas in these Islands that are exempt from one or other of our prevailing winds, the remedies that suggest themselves are: The selection of small |
|
