In order to analyze the growth of tree ferns in the Cordillera Central, between March 2006 and February 2007, the population of Dicksonia sellowiana in the Rio Blanco Reserve (Manizales, Caldas) was monitored. The DAP, total height, number and reproductive status were recorded quarterly. This information was related to precipitation and compared with specimens deposited in the COL, HUA and FAUC herbaria. The diameter increased by 1.2 cm, especially in the first 2007 season. The height growth of the stem was 6.7 cm, with the same trend. The number was stable with 9 initial leaves. Only plants with a height greater than 4 m were fertile. The results showed that D. sellowiana answers to a bimodal seasonal phenological pattern determined by rainfall, coinciding with the increased sporulation recorded in herbarium specimens. Similarly, the growth in the stem was similar to other Cyatheales species, mainly Alsophila. The emission and accumulation of leaves were seen in continuous double leaf modules, an adaptive strategy in the high Andean ecosystems, where the accumulated organic matter of slow decomposition stabilizes the microclimate. These arguments provide a basis for the development of conservation programs from the study and sustainable management of natural populations.