Best Season to Harvest Echinacea Roots

When (which season) is the best time to harvest Echinacea spp. roots?

Echinacea, like most root crops, is best harvested in the fall. Studies on other root herbs such as angelica back up the conventional wisdom that roots reach their greatest size and potency in the fall after the first frosts. In the case of echinacea, the roots are harvested in either the third or fourth year. One production model, applicable to E. purpurea, indicates that harvesting in the fourth year will produce 1100 kilograms per hectare (1000 pounds per acre).