The data cited above presents a practical problem: all were obtained under controlled conditions. In field conditions, a study of the initial phases of coffee flowering is extremely difficult since the process is highly influenced by
other factors, mainly photoperiod as the length of time plants are exposed to light determines the flowering process
(Bewley et al. 2000). Moreover, the tools used for such observations were nadequate, i.e., many studies were based on visual observations instead of histological sections. Thus, it is not possible to conclude exactly if there is an annual
cycle defining the periods of initiations and differentiation of floral buds in coffee.