Joe-Pye Weed

Plant taxonomy places the various types of this plant in the genus, Eupatorium (you'll also encounter the more recent classification, Eupatoriadelphus). I deal most specifically in this article with spotted Joe-Pye weed (Eupatorium maculatum).

Joe-Pye weed is considered a broadleaf, herbaceous, perennial wildflower. It is a member of the aster family.

Spotted Joe-Pye weed is a "weed" only in the sense that it is a wild plant (in North America). "Wildflower" would be a better name for a plant with such an attractive mauve flower and imposing presence (up to 6 feet tall!). Despite the species name, maculatum (see below), the stems often come in a solid purple that offers an even more striking look. These sturdy stems make Eupatorium maculatum a good cut flower. Flower heads are flattish; leaves grow in whorls. Eupatorium maculatum eventually spreads to form a dense stand. Click the picture above to open a mini-photo gallery if you wish to view more photos.

Indigenous to eastern North America, the plant can be grown in planting zones 4-8.

Plant in full sun and in a moist, loamy soil.

A wet area in the landscape often presents a challenge to the homeowner: many plants won't perform well there. At home in wetlands in the wild, spotted Joe-Pye weeds are a good choice when you need plants for wet soils. They are plants that attract butterflies, including tiger swallowtails and black swallowtails.

Because it is a tall perennial, it is effective in the back row of a flower bed -- in a cottage garden, for instance. At the center of a planting circle surrounded by shorter plants, it can serve as a focal point. In addition to its beauty, the plant has another selling point: it's a late bloomer, flowering in late summer and into autumn, well after most other plants in its native region have ceased flowering. As such, it can be a useful plant to grow if you wish to stagger blooming periods in your yard, as you should be doing if your goal is landscaping for the four seasons.

Besides spotted Joe-Pye weed (Eupatorium maculatum), other types native to North America are:

• Hollow Joe-Pye weed (Eupatorium fistulosum)
• Eastern or "three-nerved" Joe-Pye weed (Eupatorium dubium)
• Sweet Joe-Pye weed (Eupatorium purpureum)

Cultivars of Eupatorium are also available (see below).

Cut the prior year's stalks down to the ground in early spring. New shoots will push up from the system of rhizomes underground. The plant can be aggressive; if you wish to keep it in check, you'll have to contain the spread of the rhizomes either by cutting them or by blocking their progress with bamboo barriers or the like. Cultivars such as Eupatorium maculatum 'Gateway' are better-behaved. Pinch back in late spring to keep the plant more compact.

If you're happy with this aggressive plant and wish to increase your supply of it and grow it in an additional spot in the landscape, undertake springtime division.

Spotted Joe-Pye weed is a wildflower, but cultivars of Eupatorium are also available. Besides the mauve color shown in my pictures, some folks plant white-flowering varieties -- which shouldn't surprise those familiar with the related wildflowers, snakeroot (Eupatorium rugosum) and boneset (Eupatorium perfoliatum). Eupatorium rugosum 'Chocolate' has white blooms; its cultivar name derives from the dark splotches in its foliage.

In The Book of Perennials (p. 150), Alfred C. Hottes states that the genus Eupatorium was named "for Mithridates Eupator, King of Pontus, who discovered a species to be an antidote against poison" (others say that the species in question was, itself, poisonous, and that Mithridates consumed it in small doses to build up a tolerance to it). On the same page Hottes notes that the common name for Eupatorium maculatum, etc. "is derived from Joe Pye, an Indian herb doctor of Pilgrim days in Massachusetts. He is reputed to have cured typhus fever from a decoction of the plant."

Meanwhile, the species name, maculatum is Latin for "spotted" and refers to the fact that spotted Joe-Pye weed often bears purplish flecks on its stems.