Balloon flower (Platycodon grandiflorus 'Sentimental Blue')
Dwarf Platycodon grandiflorus 'Sentimental Blue' is a low-maintenance Balloon flower offering showy blue blooms from July to August. Ideal for borders in Zones 3-8.
Complete Plant Information
Overview
The Platycodon grandiflorus ‘Sentimental Blue’, commonly known as the Balloon flower, is a charming, compact variety treasured for its distinctive flower buds that puff up before opening. This dwarf selection provides vibrant, upward-facing, 3-inch blue, bell-shaped flowers consistently throughout the summer months. Gardeners value this perennial for its low maintenance requirements and reliability in borders and rock gardens.
As a clump-forming herbaceous perennial, the Platycodon grandiflorus ‘Sentimental Blue’ provides excellent, clear blue color contrast against summer foliage. It thrives in conditions ranging from full sun to partial shade, making it flexible for various garden placements. Once established, this variety forms a neat mound, offering substantial visual appeal with minimal fuss.
This specific cultivar remains relatively short, making it perfect for edging or container arrangements where taller landscape plants might overwhelm the view. Beyond its aesthetic appeal, dividing and transplanting the Balloon flower should generally be avoided due to its fragile, fleshy roots, encouraging gardeners to site it correctly from the start.
Fast Facts
- Plant Family: Campanulaceae
- Plant Type: Herbaceous perennial
- Hardiness Zones: USDA Zones 3-8
- Size at Maturity:
- Height: 0.5-1 ft
- Spread: 1-1.5 ft
- Bloom Time: July to August
- Bloom Description: Blue
- Sun Exposure: Full sun to part shade
- Water Needs: Medium
- Maintenance Level: Low
How to Grow
The Balloon flower performs best when planted in light, medium-moisture soils that are organically rich and, critically, well-drained. Avoid areas where water pools, as overly wet soil encourages root rot. Plant in spring or early fall, ensuring a location that receives full sun or benefits from light afternoon shade.
Watering should be consistent, aiming for medium moisture levels without allowing the soil to stay soggy. Since the Platycodon grandiflorus ‘Sentimental Blue’ has a fragile root system, established plants generally do not require regular fertilization. Deadheading spent flowers can help prolong the blooming period throughout July and August.
Be patient in the spring; new stems for the Platycodon grandiflorus ‘Sentimental Blue’ emerge late. To avoid accidental damage during early cultivation, leave the old, dried-out stems in place throughout winter. These stems serve as markers until the new growth of the Balloon flower appears. If taller stems flop, staking may be necessary, although staking should be less of a concern with this dwarf selection. If you wish to reduce height proactively, cutting stems back by half in May can help manage stature.
Landscape Uses
The compact nature of Platycodon grandiflorus ‘Sentimental Blue’ makes it an ideal choice near the front of perennial borders where its distinctive blue blooms can be easily appreciated. It excels when tucked into rock gardens, providing soft, mounding color among stones and gravel. Furthermore, its contained size means the Balloon flower is perfectly suited for growing in containers or large pots on patios and decks.
When designing mixed plantings, pair this sturdy perennial with plants that share similar sun and water requirements, such as German irises or low-growing sedums. Its mid-summer bloom fills the gap after early spring bulbs fade, offering reliable texture until later-season bloomers take over. Use the Platycodon grandiflorus ‘Sentimental Blue’ for defined edging along pathways.
Standout Features
Flower Qualities
- Showy
- Good Cut
Noteworthy Characteristics
Platycodon grandiflorus, commonly called balloon flower, is a clump-forming perennial so named because its flower buds puff up like balloons before bursting open into outward-to-upward-facing, bell-shaped flowers with five pointed lobes. The species is native to Asian slopes and meadows, producing purple-blue flowers up to 3 inches across. ‘Sentimental Blue’ is specifically noted as a dwarf selection, typically topping out at only 6-12 inches tall, featuring its signature puffy buds opening to single, blue, upward-facing bells throughout most of the summer.
Tolerances
No specific tolerances were listed in the provided data profile other than avoiding overly moist soils mentioned in care requirements.
Potential Problems
This Balloon flower generally experiences no serious insect or disease problems, offering reliably low maintenance. The primary concern stems from cultural mistakes—specifically, root rot can occur if the plant is situated in poorly-drained or overly moist soils. Gardeners should remain vigilant against slugs and snails, particularly on new, tender spring growth, employing standard bait or barrier methods as necessary.
Frequently Asked Questions
What hardiness zones is Balloon flower suitable for?
The Platycodon grandiflorus ‘Sentimental Blue’ is hardy across a wide range, suitable for USDA Zones 3 through 8.
How large does Platycodon grandiflorus ‘Sentimental Blue’ grow?
This is a dwarf type, typically reaching a mature height of 0.5 to 1 foot tall, with a spread ranging from 1 to 1.5 feet wide.
When does Balloon flower bloom?
You can expect the signature puffy buds to open into blue flowers primarily during July to August.
What sun exposure does Platycodon grandiflorus ‘Sentimental Blue’ need?
This plant adapts well to either full sun or partial shade conditions, making it quite versatile in the landscape.
Conclusion
The dwarf Platycodon grandiflorus ‘Sentimental Blue’ provides reliable, showy blue blooms throughout mid-summer with remarkably low maintenance. Its unique, balloon-like buds ensure visual interest even before the flowers open, solidifying the Balloon flower’s place in perennial borders. Before planting, confirm your garden falls within USDA Zones 3-8 and ensure the soil offers the rich, well-drained conditions it requires.
Companion Planting
Selecting companions for the Balloon flower should focus on plants that thrive equally well in well-drained, medium-moisture soils under full sun to part shade. Consider pairing it with drought-tolerant perennials that bloom earlier or later to extend color interest throughout the season. Low-growing ornamental grasses can provide textural contrast to the mounding habit of the Platycodon.
For plants that enjoy similar cultural preferences, consider pairing Salvia nemorosa varieties or hardy Geraniums. These reliable companions won’t compete aggressively for resources, allowing the unique form of the Platycodon grandiflorus ‘Sentimental Blue’ to shine. Because the Balloon flower emerges late, planting spring ephemerals nearby, like Muscari or early Daffodils, can fill the space before its foliage appears.
Container Growing
Growing Platycodon grandiflorus ‘Sentimental Blue’ in containers allows gardeners without ideal in-ground soil to still enjoy this beauty. Use a commercial potting mix amended with plenty of grit or perlite to guarantee excellent drainage, which is vital for its health. Since its roots are fleshy, ensure the container has generous drainage holes.
In pots, the need for consistent moisture may increase slightly compared to ground planting, so monitor watering closely during hot summer spells. The compact 0.5 to 1 foot height of this specific cultivar is excellent for the middle or front ring of a mixed container arrangement. Annual feeding with a balanced liquid fertilizer applied sparingly during active growth can support robust flowering.
