The excision of the inflorescence of Zantedeschia aethiopica Spreng. and its substitution by the cytokinin 6-(o-hydroxybenzylamino)-purine and its riboside 6-(o-hydroxybenzylamino)-9-β-D-ibofuranosylpurine, previously isolated from Z. aethiopica fruits showed that these cytokinins present in fruits are correlated with the self-inhibition of senescence. The determination of chlorophyll levels revealed that both base and riboside promoted regreening, 241–300% over 30 days compared with 341% after normal fructification, the riboside being the most effective (at 10−8 M). Electron microscopic observations on palisade parenchyma cells showed that the reapplied endogenous cytokinins produced an increase in the cytoplasmic and chloroplastidial ribosomes. At the same time that the stroma was restructured, osmiophilic material and starch diminished. The formation of thylakoids begins in osmiophilic dense regions. The sequence of these events is responsible for the regreening and complete restructuring of spathe palisade cells where well structured and functional chloroplasts are evident.