Fall perennial care: What to prune and divide now

As temperatures cool down, the garden seems to come alive again, especially with the recent rains. Dahlias, zinnias, and phlox all appear to deepen in their colors, providing one last burst of beauty before frost arrives. Once the first frost arrives, typically by mid-to-late October, it’s time to prune many perennials and divide them if needed to promote healthy blooms in the spring.