Virtues: False sunflowers (Heliopsis helianthoides) are great perennials for adding bulk to the border, providing long-lasting color and drawing bees and butterflies. We love the selection Summer Sun for its height, strong stems and its ruffly golden flowers that can last into autumn.
Common name: ‘Sommersonne’ or Summer Sun heliopsis, false sunflower or ox-eye daisy
Botanical name: Heliopsis helianthoides var. scabra ‘Sommersonne’ or Summer Sun
Flowers: Bright gold petals surround a darker gold central disk. Summer Sun heliopsis can have a double row of petals, giving the flowers a ruffled look.
Foliage: The leaves of Summer Sun heliopsis differ from those of the straight species (H. helianthoides) and its cultivars in that they are thicker and hairy.
Habit: Summer Sun heliopsis has an upright shape, growing 2 to 3 feet tall and about 1.5 to 2 feet wide.
Season: Midsummer to autumn, for flowers. Deadheading prolongs false sunflower’s bloom.
Exposure: False sunflowers bloom best and maintain a better habit in full sun, although they tolerate part shade.
Origin: Summer Sun is a cultivar of a Heliopsis species native to parts of the United States’s South, Midwest, Mid-Atlantic, Northeast and much of eastern Canada.
How to grow Summer Sun heliopsis: Site this perennial in full sun, in well-drained soil. It is tolerant of poor soil and different soil types as long as the drainage is good. Provide heliopsis with moderate water, about an inch a week. However, it will tolerate periods of drought once it is established. Summer Sun false sunflower will bloom into autumn if it is deadheaded; however, letting the spent flowers remain on the plant and go to seed will draw birds and encourage self-sowing. Self-sowing may be desired because the plant is naturally a short-lived perennial. Summer Sun will come true from seed (that is, seedlings will look identical to the parent plant). USDA Zones 3–9.
Image courtesy PerennialResource.com (Walters Gardens)