Growth and yield of Echinacea purpurea L. as influenced by planting density and fertilization

Echinacea purpurea L. plants, cultivated with 20, 40, or 60 cm between plants and in rows 50 cm apart, had increased height, vegetative dry weight, roots, and flowering heads at the 60 cm spacing. Total biomass per unit production area, however, was greater at the 20 cm spacing. Application of nitrogen fertilizer improved plant growth end yield. The addition of a low level of potassium gave better results then nitrogen alone. The results confirmed the importance of a balanced N:K ratio.