Content Detail

Named for the playful, inflated flower buds, balloon flower has large, bluish-purple, bell-shaped flowers that grow on the ends of tall stems filled with blue-green leaves. Balloon flower blooms from early summer into late summer. It prefers full to partial sunlight in average, well-drained soils. They can be grown in rock gardens, containers, beds, or borders.

  • Family (English) Bellflower
  • Family (botanic) Campanulaceae
  • Tree or plant type Perennial
  • Native locale Non-native
  • Size range Medium plant (12-24 inches), Large plant (more than 24 inches)
  • Light exposure Full sun (6 hrs direct light daily), Partial sun / shade (4-6 hrs light daily)
  • Hardiness zones Zone 3, Zone 4, Zone 5 (Northern Illinois), Zone 6 (City of Chicago), Zone 7, Zone 8
  • Soil preference Moist, well-drained soil
  • Tolerances Alkaline soil
  • Season of interest early summer, midsummer, late summer
  • Flower color and fragrance Blue, Purple
  • Shape or form Upright
  • Growth rate Moderate
  • Wildlife Birds, Butterflies, Insect pollinators

More Information

Size and Method of Spreading

Balloon flower is between 1 to 2 ½ feet tall and 1 to 1 ½ feet wide at maturity. They spread by self-seeding.

Native Geographic Location and Habitat

Balloon flower is native to the eastern side of Asia, including China, Russia, Korea, and Japan.

Attracts Birds or Pollinators

Balloon flower attracts bees, birds, and butterflies.

Leaf Description

The blue-green leaves of balloon flower are lance shaped (lanceolate) with numerous sharp teeth along the edges (serrate margins). They can reach up to 3 inches in length. The leaves attach to the stems directly (sessile) or on short stalks (petioles). They alternate up the leaves or occur in whorls. 

Flower Description

The balloon flower name comes from the puffy flower buds, which resemble small hot air balloons. The flowers occur singly or in small clusters at the terminal ends of the stems. When the buds first appear, they are pale green. As the flower matures, the buds seem to inflate, and darken from green to bluish-purple. The tubular petal-like structure (corolla) has five equally sized, pointed lobes at the tip. When the buds open, the lobes separate to reveal a large, slightly flattened bell-shaped flower. Surrounding the base of the corolla is a leaflike, tubular structure (calyx) with five sharply pointed lobes at the tip. The five pollen-bearing structures (stamens) protrude from the center of the tubular corolla and surround the ovary. The ovary is mostly hidden within the base of the corolla, but the tip (stigma) extends beyond the stamens and divides into five spreading sections.

Fruit Description

The fruit of balloon flower is a brown capsule with five valves that open from the top of the fruit at maturity. It is ovoid in shape and tapers to a conical top before opening to release seeds. The lobes of the persistent calyx are situated opposite of the valves of the fruit.

Care Knowledge

Plant Care

Balloon flower does not transplant well, due to the fragility of the roots. Take care not to overwater to prevent root rot. Deadheading extends the blooming period. Tall plants may require staking, but dwarf cultivars are available. 

List of Pests, Diseases, and Tolerances

Balloon flower is susceptible to root rot in overly wet soils, as well as damage from slugs and snails. It is deer resistant.


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