Am I supposed to deadhead Salvia, Echinacea, Rudbeckia, and Bee Balm? Is there a rule of thumb for deadheading flowering perennials?
All of the perennials you mentioned, (Salvia, Echinacea,
Rudbeckia, and Bee Balm) as well as many others, can and should be
deadheaded, to promote more blooms and to keep the plant from going to
seed. (If they are not deadheaded, the plant uses energy to form seeds
instead of producing more buds.) Just follow the stem down to the base
of the plant and cut it off.
In the fall, it’s not necessary to cut back the foliage. Many
gardeners leave the foliage to create winter interest, and to catch
the snow for a natural protective cover. In the spring, when you start
to notice the first green shoots sprouting, then you can cut back the
dry brown stalks. Thank you for your question!