This research was aimed to compare the postharvest performance of the disease caused by the fungus Botrytis cinerea Pers., as well as the Petal Blackening in roses grown in greenhouses cover with plastic of different transmittance to the ultraviolet light. Furthermore, the effect of a climatic screen over the two problems was evaluated. The trial was done in the Centro de Investigaciones y Asesorias Agroindustriales located in Chia, Cundinamarca, under greenhouses with the same features as the ones used in commercial rose cultivation, with the varieties Eterna and Madame Delbard and its clones 13 and 15. The effect of the plastic over the disease made a clear difference, showing a lower development of the diseas e in the greenhouse covered with photoselective plastic, as compared with the commercially used plastic. A lower effect of this cover was found related to the Petal Blackening, where the results were rather similar between the two plastic types. The climatic screen did not show difference over any of the two problems, under these conditions. The effect of the varieties was not very clear related to the disease, but it in fact was in relation to the Petal Blackening, in which the variety Madame Delbard showed a better performance than its clones 13 and 15. No effect was shown in the interactions between the factors.