The experiment was carried out in the Teaching and Research Workshop on Horticultural Plants (TEIPH) of the Faculty of Agronomy-UNAP. The research was experimental, explanatory with an independent variable (planting distance) and eight dependent variables (plant height, root length, root weight, number of leaves/plant, bulb diameter, total plant weight, bulb/plant weight and bulb weight/ha); The objective was to determine the influence of planting spacing on the agronomic characteristics and yield of Allium porrum L. "poro". The experimental design was the completely randomized block design, with four treatments and four repetitions. Each experimental unit consisted of 3 rows, 12 plants/row, in T1 (0.20 m. x 0.30 m.); 8 plants/row in T2 (0.30 m. x 0.30 m.); 6 plants/row in T3 (0.40 m. x 0.30 m.) and 5 plants/row in T4 (0.50 m. x 0.30 m.); the sampling unit consisted of three plants/exper...