Discover the best perennial flowering plants for USDA Zone 5. Learn about hardy, beautiful options to create a stunning garden that blooms year after year. Expert tips and care advice included. The best perennial flowering plants for USDA Zone 5 include Coneflowers (Echinacea), Black-Eyed Susans (Rudbeckia), Daylilies (Hemerocallis), Peonies (Paeonia), …