Globe thistle is a clump forming herbaceous perennial native to Asia and central to eastern Europe. It is a member of the aster family, Asteraceae, that also includes daisy, yarrow and lettuce. Plants grow 2-3′ tall from a tap root and have stiff stems carrying coarse, gray-green spiny leaves that are lobed and have whitish downy undersides. The leaves from a rosette from which the flowering stalks arise with their 1-2″ wide steel blue globose flowerheads that bloom 6-8 weeks starting in mid-summer. The plants have a unique look in the garden and add a very different texture than most other plants. The flowerheads attract bees and butterflies, are spectacular in fresh arrangements, and can be dried if picked before they reach their full color. The genus name, Echinops, comes from the Greek words echinos meaning hedgehog, and ops meaning appearance, and refers to the appearance of the flowerheads. The specific epithet, ritro, may be an old name for a plant with thorns dating back to the mid-1660s.
Type: Herbaceous perennial.
Bloom: Two inch wide steel blue globose flowers bloom in mid-summer or 6-8 weeks.
Size: 48-60�H x 24-48� W.
Light: Full sun.
Soil: Average, moderately moist to dry, well drained, neutral to alkaline soil. Drought tolerant when established.
Fertilizer: Moderate as over fertilization reduces the blooming season.
Hardiness: Zones 4-9.
Care: Very little needed. If the foliage gets ratty after bloom cut it back to tidy up the garden.
Pests and Diseases: None of importance.
Propagation: Plants will reseed but not enough to be invasive. Basal plantlets may be separated from the base of the plant when the plants are at least 3 years old. Two to three inch root cuttings may be taken in spring.
Companion plants: White garden phlox (Phlox paniculata) �David�, lemon daylilies such as �Hyperion�, �Moonshine yarrow, �Moonbeam� coreopsis, pink roses such as �The Fairy� and coneflower (Echinacea purpurea �Magnus� and other pink cultivars).
Comments: Best used in drifts rather than as specimen plants.
