A viable alternative for the final disposal of Cocos nucifera L. waste is its use in the production of substrates to grow seedlings of vegetal species. We carried out an experiment at the Federal Institute of Ceará, Quixadá campus, to assess the technical viability of this alternative. During the experiment, seedlings of Caatinga species (Libidibia ferrea, Cenostigma pyramidale, and Amburana cearenses) were planted in the following treatments: T0 -70% soil + 30% bovine manure, T1 -70% soil + 20% bovine manure + 10% coconut powder, and T2 -70% soil + 20% bovine manure + 10% coconut fiber. In each treatment, we used ten seedlings per species, in a completely randomized design. First, we calculated the percentage of emergence, then, monthly, we measured the height and diameter of seedlings. After four months of the experiment, we analyzed the investment in morphometric characteristics. The use of coconut waste favored the emergence percentage of L. ferrea and C. pyramidale, but not A. cearenses. The presence of coconut powder provided an increase in maximum height and diameter, primary root length, wood density, and dry matter content in L. ferrea seedlings, and a higher dry matter content in the wood and secondary roots of C. pyramidale seedlings. Thus, we concluded that the use of coconut waste, mainly powder, has positive or neutral effects on the growth of L. ferrea and C. pyramidale seedlings, besides being an environmentally suitable alternative for the final disposal of this material.