Komachi
Komachi is a distinctive form of Platycodon grandiflorus whose buds inflate and often remain as balloons rather than opening flat. It grows best in full sun to light shade with well-drained, fertile soil. Garden trials recorded a long bloom window from late July into mid September. Plants may be much taller in some seasons than catalog listings suggest.
At‑a‑glance
Group/Class: novelty double/ballooning form
Height × spread: 12-47 in (30-120 cm) × 20-34 in (50-85 cm)
Bloom window: late July to mid September
Color & flower form: lavender-blue; inflated double buds that rarely open
Fragrance: 0 none
USDA hardiness: zones 3-8
Breeder / Year / Origin: unknown
Cut-flower notes: novelty buds; sear cut ends; condition before arranging
Pet safety: unknown
How it differs
- Buds often stay inflated rather than opening.
- Can be much taller than many sources list.
- Stems may need support due to height.
- Flower size is smaller than on many tall strains.
Strengths
- Unusual, conversation-starting flower form.
- Extended summer interest from persistent balloons.
- Cold hardy to zone 3.
- Useful as a tall accent where space permits.
Care in one minute
Light: full sun for strongest stems; light shade tolerated.
Soil: fertile and well-drained; slightly acidic to neutral pH.
Water: regular moisture; prevent standing water.
Feeding: moderate fertilizer; avoid excess nitrogen.
Grooming: deadhead spent blooms; cut stems back by half in late spring to manage height.
Winter: mulch lightly and mark clumps; shoots emerge late.
Watch‑outs
- Height can exceed expectations in fertile soil.
- Stems may flop without staking.
- Avoid wet soils to reduce root problems.
Best uses (tags)
borders, cutting, tall accents, cottage gardens
Provenance note
Public garden profiles note that Komachi is sold as seed and may self-seed, and that the balloon-like buds rarely open.
References
- Chicago Botanic Garden – Platycodon cultivar trial (Komachi notes and measurements)
- Missouri Botanical Garden – Platycodon grandiflorus ‘Komachi’ (Plant Finder)
- Missouri Botanical Garden – Platycodon grandiflorus species profile
- RHS – Platycodon grandiflorus species profile
Written by: Your Flowers Guide editorial team
We are a small independent group of flower lovers who research and review each guide using trusted horticultural and educational sources. Learn more about us