Hyssop boneset is found in meadows. Good choice for restoration and conservation or use as an ornamental.
FIRST IMPRESSIONS: Eupatorium hyssopifolium is a fine textured vase shaped perennial. Foliage is narrow and gray green. In late summer plants are covered with dense flat terminal clusters of white florets. The clouds of flowers attract a myriad of pollinators. This species thrives in well drained or dry sites with sun or part sun.
HABITAT & HARDINESS: Eupatorium hyssopifolium occurs in the eastern United States from Massachusetts to Florida and west to Missouri and Texas. Distribution is widest in the coastal plain.
Plants are indigenous to dry grasslands, sandy or gravelly fields and roadsides, rights of ways, dry open woods and salt meadows.
This species is hardy from USDA Zones 4-8.
PLANT DESCRIPTION: Eupatorium hyssopifolium is an upright perennial wildflower that produces multiple stems from short rhizomes.
Stems are clothed in linear gray green leaves. Blades are 4” long and less than ½” wide. They taper at the base and tip and are arranged along the stems in whorls of 4.
From mid-summer until autumn, plants bear terminal flat topped flower corymbs that range from 4-10” across. The budded florets show color for several weeks before expanding into small feathery white disk florets.
The late season flower displays are magnificent especially when plants are massed. The blossoms mature into soft buff colored seed clusters that mingle nicely with flowering autumn grasses.
Plants are 2-4’ tall with an average 2’ spread.
CULTURAL & MAINTENANCE NEEDS: Eupatorium hyssopifolium prefers full to part sun. Plants require good drainage and thrive in mesic or dry sandy soils.
This species is pest resistant and foliage is unpalatable to deer and other herbivores.
LANDSCAPE USES: In bloom, Eupatorium hyssopifolium is a dramatic Accent for a Wildlife Garden or Meadow. Plants are lovely in combination with native grasses and golden fall flowers. Plants are also used as Butterfly Nectar Plants, Cut Flowers or as part of a Grouping or Mass Planting. This wildflower has Showy Blooms and provides Erosion Control. It can be used in Cottage Gardens, Deer Resistant Plantings, Rain Gardens, Water-wise Landscapes, Low Maintenance Plantings or Perennial Borders.
COMPANION & UNDERSTUDY PLANTS: Try pairing with Aster laevis, Echinacea purpurea, Monarda fistulosa, Liatris spicata, Rudbeckia fulgida var. fulgida, Solidago rugosa ‘Fireworks’, Sorghastrum nutans, Schizachyrium scoparium or Andropogon virginicus,
Eupatorium coelestinum is a possible substitute if blue flowers are acceptable. The two plants have similar height, flower shape, cultural needs and bloom time. Although Eupatorium hyssopifolium, however, will tolerate drier sites and more drought.
TRIVIA: Unlike other members of the Aster Family, Eupatorium spp. flowers are composed only of disc florets with no rays.
Flowers attract butterflies, skippers, moths and native bees. This species is particularly valuable to beneficial insects.
Eupatorium hyssopifolium (or hyssop leaf thoroughwort) along with the closely related E. perfoliatum are members of the Thoroughwort Tribe. Plants are occasionally called justice weed because in the 1800’s this species was used medicinally by South Carolinian John Justice to treat rattlesnake bites.
Eupatorium hyssopifolium has been lauded as a champ for dry meadows and an underused garden gem by the likes of Tony Avent and Rick Darke. To see this spectacular species in full autumn flower, visit Longwood Gardens in September. Or peruse internet photos of the Meadow Garden and Hourglass Lake where this lovely is massed majestically.
For more information on this plant, visit the USDA PLANTS Database: http://plants.usda.gov/java/profile?symbol=euhy