In order to obtain: - The dry matter production of butterfly pea under field condition from 41 to 146 days. - Concentration and extraction of the macronutrients. A field trial was executed on a soil called Latossolo Vermelho Escuro, serie "Luiz de Queiroz" (ORTHOX) at Piracicaba, SP, Brazil. Plants were harvested every 15 days when the plants were 41 days old. The plants were divided into leaves, stems, flowers and pods. The material was dried a 75°C and analysed for N, P, K, Ca, Mg e S content. The experimental design was a complete randomized experiment with four replications. The authors concluded: - The dry matter production is very intensive from the begining to the 131 days old plants. - At 86 days the plant presented the following concentrations of the elements in the leaves: N% - 3-96; P% - 0.32; K% - 2.30; Ca% - 0.85; Mg% - 0.43 and S% 0.15. - For the same age the plant presented the following amounts of the elements: N mg - 322; P mg - 31; K mg - 219; Ca mg - 71; Mg mg - 39; S mg - 16.