HARDINESS: Zones 4 to 8
PREFERRED SOIL pH: Near neutral
PREFERRED SOIL TYPE: Average, moist
PREFERRED LIGHT: Sun to partial shade
ATTRIBUTES: Tall plants with large pink or white flowers; for the back of the border
SEASON OF INTEREST: Midsummer to fall
FAVORITES: Pink-flowered 'Atropurpureum', smaller 'Gateway', white 'Bartered Bride'
QUIRKS: For compact growth, cut plants back by one-third in late spring
GOOD NEIGHBORS: Daylilies, goldenrod, garden phlox, rudbeckia, ornamental grasses
WHERE IT GROWS BEST: Damp soil and full sun
POTENTIAL PROBLEMS: Fungal powdery mildew, leaf spot; grasshoppers, flea beetles
RENEWING PLANTS: Lives for years; divide crowded clumps 5-6 years in spring or fall
CRITTER RESISTANCE: Good
SOURCE: Bedding plants, division
DIMENSIONS: 4-7 ft (1.2-2.1 m) tall, 3-4 ft (1-1.2 m) wide
Joe Pye Weed in the Landscape
When you want a statuesque plant to fill the back of the border or line a fence, Joe Pye weed is a prime candidate. Improved varieties of this North American native from damp meadows are an asset to any sunny garden.
The flower clusters are big enough to balance the tall stems visually but won't topple them, thanks to strong stalks that don't need staking. Because Joe Pye weed attracts little attention through the first half of summer, it is a good plant to set behind daylilies, rudbeckias, ornamental grasses, or other perennials. Or you can use it as a backdrop for zinnias and other tall annual flowers.
Standing up to 7 ft (2.1 m) tall, with long, pointed leaves growing in whorls around thick stems, the widely available 'Atropurpureum' is nothing less than colossal. Its clusters of dusty pink flowers burst into bloom in mid to late summer and last for weeks. If you prefer shorter plants, cut the stems back by a third in late spring. They will rebound and flower but stand at least 1 ft (0.3 m) shorter than untrimmed plants. Another option for shorter plants is to grow 'Gateway', a dark pink-flowered version that tops out at 4-6 ft (1.2-1.8 m). Another popular cultivar, 'Bartered Bride', features attractive white flowers.
Joe Pye weed's fragrant flowers entice man and insect alike. The large clusters of tiny nectar-rich flowers make a good landing pad and sipping station for butterflies. On a warm, drowsy summer day, a single plant may be covered with dozens of swallowtails.
Growing Joe Pye Weed
Don't fret if Joe Pye weed is slow to emerge in spring. This hardy perennial is rarely winter-killed and makes up for lost time when it does emerge. However, this is a shallow-rooted plant that needs to be grown where it won't be disturbed, in a sunny spot with moist soil. Joe Pye weed wilts in dry weather but is unequaled for tolerating standing water. This energetic grower is also a big feeder. Spread a 2 in (5.1 cm) thick layer of composted manure over the dormant plants every spring to keep them at their peak of perfection.
Watch for fungal diseases typical of overly moist sites: powdery mildew and fungal leaf spot. Thinning stems to promote better air circulation is a good preventative. If you do see white powdery or dark sooty spots on leaves, remove and dispose of the affected foliage. The symptoms will naturally diminish in drier weather.
While insects don't inflict life-threatening damage, grasshoppers and flea beetles sometimes chew the leaves in late summer.The possibility of unsightly late-season foliage is a good reason to keep Joe Pye weed at the back of the border, where its lower leaves are hidden from view.
Plants can grow for many years undisturbed, but if a clump becomes overcrowded, or if you want to increase your stock, lift and divide the clumps in early spring, or in fall in mild climates. When replanting, set the divisions at the same depth at which the parents grew.