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The objective of this experiment was to evaluate the effect of two sowing densities (17 850 and 11 350 plants/ha) and four planting dates (July, August, September and October 2009) on the establishment of Pennisetum purpureum cv. ’CT-115’. A split-plot design with two repetitions for whole plots was employed and planting dates were randomly assigned. Sowing densities were randomly assigned to the split-plot within each whole plot. Seven plants were randomly sampled in each experimental unit to estimate leaves, stems and senescent material proportions, leaf:stem ratio, dry mater (DM) percentage in stem, number of stems/plant and DM yield (g m(-2)). Temperature and precipitation were recorded during the two years. Grass establishment was evaluated on May of 2010. The two frosts (-6 degrees C) recorded during two consecutive days on January of 2010 did not affect ’CT-115’ grass establishment since normal re-growth was observed on April. Sowing density affected (P <= 0.05) the ratio of senescent material, which was 15.8 vs. 11.4 % for the sowing densities of 17 850 and 11 350 plants/ha, respectively; it did not however affect (P > 0.05) dry matter yield. There was less (P <= 0.05) DM in stems of plants sowed on July and August than in further planting dates. Likewise, leaf proportion was higher (P <= 0.05) in those early months (57.7 and 58.5 %; respectively). Leaf:stem ratio and number of stems/plant were higher (P <= 0.05) in the two first months of planting. It was concluded that dry matter yield was not affected by sowing density or by planting dates, and that the two frosts in January of 2010 did not affect the establishment of ’CT-115’ grass, in spite of its tropical origin.