Eupatorium maculatum, or Joe Pye Weed, is one of the many purple flowers that grace the ditches, wild areas and gardens of Bath each autumn. Bath Garden Club recommends this large, easily grown plant.
Even if you’re not familiar with their names, it’s likely that you’ve noticed Joe Pye Weed and Ironweed, the tallest and most impressive of the fall-blooming wild asters. About six feet tall, and two to four feet wide, Joe Pye Weed has rounded flower heads in mauve, while Ironweed has flat flower tops in a dark, rich “royal” purple. Joe Pye Weed may be a bit wild and large for your garden, but there are members of the Eupatorium family to provide a plant for most home gardens.
E. Purpureum, commonly known as “Purple Boneset” is considered an herb as well as a wildflower. Long used as a garden ornamental, it was believed to help heal broken bones. Perhaps the star of garden plants in this group is “Hardy Ageratum,” E. Coelestinum. In late summer and fall, Hardy Ageratum is covered with fuzzy blue-purple flowers, looking very much like our annual ageratum “on steroids.”
Hardy in zones 3 to 10, all Eupatorium like moist soil and sun to part sun. Once established, these plants are both drought and deer resistant. Some, especially “Boneset,” are fragrant, and they are all a favorite of butterflies. Plants in this group spread quickly through shallow tuberous roots, so plant them where they will have plenty of room. They can be divided and moved every two years, and you can pinch them in early summer for shorter, bushier plants that bloom a little later.