The aim of this study was to evaluate the effect of solubilizing phosphate bacterias (BSF), Kocuria sp. and Bacillus subtilis, on the development of coffee seedlings Castillo variety. The experiment was conducted in a greenhouse condition, in Palmira, Colombia during 2013-2014 years. The experimental design was completely random, with nine treatments and ten repetitions. The treatments were established under three types of substrates for the seedlings: natural soil (Typic Melanudand) + decomposed coffee pulp (1:1) lacking or presenting BSF (treatments 1-4), natural soil + decomposed coffee pulp (1:1) + phosphate rock (RF) with or without microorganisms (treatments 5-8), and natural soil without BSF subjected to fertilization with diammonium phosphate (DAP) (treatment 9). The application of decomposed coffee pulp with and without RF and BSF favored the availability of phosphorus that helped to the development of coffee seedlings, the above was reflected in the chemical analysis of the substrate and the response of variables, root and total dry aerial weight. Length and volume root, foliar P and recovery phosphorus efficiency (ERF), did not present significant differences. 

Keywords: solubilizing phosphates, phosphorus in the soil, biofertilizers.