Low and erratic seed germination presents a major production problem in the medicinal plants that collectively are called echinacea or purple coneflower (Echinacea angustifolia and E. pallida). In this study, nine seed lots of each E. pallida and E. angustifolia from a wide variety of commercial sources and germplasm collections were collected and treated with a solution of 1.0 mm [144.5 mg·L-1 (ppm)] ethephon (2-chloroethylphosphoric acid) to determine whether ethephon would sufficiently improve seed germination to be used by industry to improve the quality of echinacea seed. Applicationof ethephon increased seed germination in both E. pallida and E. angustifolia seed lots regardless of seed sources. The increase in germination by ethephon in eight seed lots of E. pallida and four seed lots in E. angustifolia were statistically significant compared to the nontreated control seeds. The increases in germination were also significant across seed lots for both species. Average germination increases across all seed lots were 1271 and 29% for E. pallida and E. angustifolia, respectively. Average germination of ethephon treated-untreated control seed lots was 76% to 27% and 79% to 62% for E. pallida and E. angustifolia, respectively.