Hi, a client has asked our Master Gardener plant clinic to identify this plant, but we just don't have much to go on. Can you help? Here's the information we have: This plant came in with our planting soil and comes back each spring. But they don't seem to spread or reseed themselves. They look like this when they blossom but with tiny white flowers on them, then turn this purplish color. Then they just kind of dry up in the fall but don't stick to clothing etc.
For the start: The stem looks round - not Lamiaceae. There is no bracts of the flower head - not Asteraceae.
She has offered to send a photo when the flowers bloom next year. I'll post them here when she does. Thanks for looking!