I dug up some echinacea roots a couple weeks ago. This is not only an important immune stimulating herb but also has antiviral activity making it an important herb for cold season. Although the active principles may be more concentrated in the roots, you can certainly find them in the leaves and flowers too. In the summer if I have flowers that break off I will just dry them and mix them with roots that I dig in the fall. I usually wait until the plant is 3 years old before using to be sure it has a good root system. Echinacea will reseed rather freely so I typically have several clumps growing in various places, so digging up one clump still leaves me with other clumps.
To do this, I use a shovel to dig up the roots, shake and break off the excess dirt and cut off the dead stems. I then bring the roots into the house and use a vegetable brush to clean the dirt from the roots; cutting some apart as necessary. I then let the root clump dry and will store it in a glass jar until needed. A coffee grinder can then be used to grind the roots into smaller pieces that can then be used to make tinctures or teas. Echinacea is an important part of my Thyma-Flu product.