ISSN: 1659-2751



Evaluation of Slow-release Fertilizers for Sports Fields


An experiment was conducted at EARTH University in Guácimo, Limón, in Costa Rica to develop slow release fertilizers and to evaluate effects on turf production and leachate quality. Fertilizers produced were: Varnish coated (CB), oil paint coated (PA), iron sulphate mixed with cassava starch (SH), cassava starch pellet (PLT) and peat mix (PD). Solubility test in water were carried out to select the least soluble fertilizer. The peat mix (PD) fertilizer presented only 1% solubility in water and was selected for field test and compared with the commercial product Osmocote 38-0-0 (PCO) and urea 46-0-0 (U46) fertilizers. A randomized complete block design with three treatments and three replications were established on bermuda grass (Cynodon dactylon). Plant color, density, biomass production and nitrogen loss were measured. Plant color and density were best for the PD fertilizer treatment with a reading of 9 for dark green color on a scale of 10. There was significant differences between treatments in plant biomass production (p<0.05). The PD and PCO fertilizer treatments produced higher biomass dry weight than the U46 treatment but the quantity produced varied with time. Highest biomass production was registered in the last week of the experiment. Nitrate loss was lower for PD fertilizer treatment (<10 mg/L).

Key words: diffusion, slow release fertilizers, leaching, polymer, volatilization.

Artículo en español (pdf) (909)