Fertilizer, Flower Bud Removal and Vegetative Pruning of Echinacea species (Purple Coneflower) Influence Biomass and Phenolic Content

Abstract

Purple Coneflower [Echinacea sp. (Asteracea)] is of great value to the horticultural, pharmaceutical, and herbal industry. More research is needed to determine cultural practices that will produce a plant high in biomass and phenolic content, the chemical used for testing the quality of the harvested plant on a percent basis of roots, flowers and vegetative parts. The objective of this experiment is to determine if biomass and phenolic content of Echinacea purpurea and E. purpurea `Magnus' is influenced by fertilization after flower bud removal and vegetative pruning. The second objective of this study is to form an evaluation of the differences in biomass and phenolic content of five cultivars of E. purpurea and five species of Echinacea. Biomass and phenolic content will be evaluated to determine if exposing these plants to various treatments increases the quality of the plant over 1 and 2 years of growth. Differences in dry weights of Echinacea species and cultivars harvested after the first year of growth was determined. There was a significant difference in total dry weight between E. purpurea cultivars. Echinacea purpurea `Bright Star' and `Clio' significantly produced the most total dry weight compared to all other cultivars. There was no significant difference in root or flower biomass between cultivars. Biomass of Echinacea species was significantly different in root, vegetaive and flower parts. The total biomass of E. purpurea and E. tennesseensis was significantly higher compared to other species. Echinacea pallida and E. paradoxa were not significantly different from E. purpurea in root biomass, even though both species were small in above ground growth. Echinacea tennesseensis significantly produced 45% to 105% more flowers compared to other species. Differences in phenolic content between species and cultivars will also be presented.