In spring and summer as I’m tending my gardens at home and at school, I click into keep/discard mode. It’s usually pretty straightforward: keep what I planted, discard the rest. But inevitably I pause at the same spot every year, stymied: What is this rangy, tough-stemmed plant that’s pushing upward with such determination? I’m sure I didn’t plant it. A friend wanders by, sees me studying it, and offers an opinion. “A weed, for sure.” I’m not so sure. There are no visible flower buds, nothing that promises to enhance summer’s blossoming and entice insects and hummingbirds. Just some thin, jagged leaves, a reddish stem, and a branching pattern that suggests…something. Something that convinces me to let it be, to wait and see.
I’m glad I did. The plant that I decided to ignore all summer just waited as the sunflowers, coneflowers, and black-eyed Susans burst into bloom, flashed their gaudy petals (or were eaten by the deer), and then became food for the finches. Finally, as I was contemplating spreading compost and putting the beds to bed for the winter, I noticed it. Actually, what caught my eye first were its visitors: sulphurs, monarchs, skippers, buckeyes, wasps, bees, ants.
A stunning array of insects worked over the inconspicuous, delicate white flower heads. I hardly knew where to look first, much less how to focus my camera lens to capture the abundance. Only then did the identity of the plant finally enter my consciousness: late boneset, also known as late thoroughwort. Eupatorium serotinum. Pollinator magnet.
This is not the only “weed” that waits until late summer to attract pollinators. Goldenrod, aster, ironweed, blazing star, and a host of other plants welcome visitors through September and into October in this region. Why so late? Many late-season pollinator species overwinter as larvae or use the nectar derived from fall flowers to fuel migration southward.
E. serotinum won’t be forgotten next year. I’ve submitted photos to the Maryland Plant Atlas, which has no formal record of it for either the Cockeysville (Jemicy LMS) or Reisterstown (my house) quad, in spite of its ubiquity. Better late than never!