Coffee cannot be grown just anywhere, it is limited to places with the right water availability, sun intensity, wind and soil type. Since it is a tropical species it can be found only in the tropical regions, roughly between 25 and 30 degrees latitude. Here there is no frost as coffee plants do generally not survive temperatures below 0 degrees. The optimal temperature differs between species. So does Coffea arabica prefer temperatures between 15-22 degrees whereas Coffea canephora has a higher optimal temperature of 22-28 degrees. Keeping a constant temperature is key to a good coffee plant with an optimal coffee bean production. However, you can imagine this might be a problem if you are solely dependent on natures will and climate change is giving some trouble to the coffee farmers. Moreover, as already mentioned, temperature is not the only key variable. Rainfall is one of the other variables having an effect on the coffee harvest. Large quantities of rainfall (1500-3000 mm per year), evenly spread, are necessary. However, key is a dry season of 2-3 months which will induce flowering and fruiting in the coffee trees. Moreover, this dry season makes the harvesting and drying of the beans much easier as well. The soil type/topography has to be so that water retention is reasonably well and root formation is possible. This will ensure that the coffee plant has enough water in the period that it does not rain. Those main requirements do not fit just any site in the world, however the so-called coffee belt shows the countries that do fulfill the coffee plant requirements (See figure 6) (Descroix, 2004).