Response of Vegetable Amaranth to Plant Spacing

ABSTRACT Field studies were conducted in the summer of 1997 and 1998 to determine the influence of three within-row plant spacings (0.3, 0.6, and 0.9 m) on the growth, yield, and mineral composition of vegetable amaranth (Amaranthus cruentus L.). In 1997, root and shoot fresh weights per plant, stem diameter, leaf dry matter, shoot dry weight and marketable yield per plant increased as plant spacing increased, whereas, plant residue cover and marketable yield per hectare increased as plant spacing decreased. Leaf Ca increased as plant spacing increased before seedhead formation, whereas leaf P, K, and Ca similarly increased after seedhead formation. In 1998 root fresh weight, stem diameter, root dry weight, and marketable yield per plant increased as plant spacing increased, whereas, plant residue cover and marketable yield per hectare increased as plant spacing decreased. Although plant spacing did not affect leaf N, P, K, Ca, and Mg content before seedhead formation, both P and Ca increased as plant spacing increased after seedhead formation.