I'm in Montreal, Canada zone 5a-5b (USDA zone 4), and although I add lots of compost types as well as fresh wood mulch yearly, my soil will remain fairly rich in clay. Which ferns indigenous to the Eastern seaboard will do well with clay, besides Athyrium filix-femina?
All of these should do well in zone 5 (they're native to the eastern US and Canada). Note that the ostrich fern can run quite a ways and become a nuisance in the garden. They're great in woods, though.
- Ostrich Fern (Matteuccia struthiopteris)
- Interrupted Fern (Osmunda claytoniana)
- Cinnamon Fern (Osmunda cinnamomea)
- Royal Fern (Osmunda regalis)