Foxglove is a biennial, not a perennial. It may reseed, but it wouldn't be the same plant from year to year.

I'm aware of that, Rob. As I wrote, the plants seed, the seeds germinate, and the new seedlings grow through the fall but they don't survive the winter to bloom the following year. I have tried mulch and no-mulch and neither seemed to help them survive.

Biennial means, that, even if the seeds grew, they'd just be plants year one, followed by flowers year two. Maybe you're pulling seedlings? God forbid!

:)

Try another brand or variety of foxglove this year. Sow in late summer. Don't mulch foxglove seedlings over winter. Leads to rot. Plant them where they won't be subjected to too many freeze/thaw cycles.