Balloon Flower/Platycodon Grandiflorus
The common name of this delightful plant from Eastern Asia arises from the inflated flower buds which, just before opening, resemble balloons: the open, cupped flowers of Platycodon grandiflorus look much like the blooms of the closely-related Campanula – both belong to the Campanulaceae family. Several different cultivars are available in blue and in white, and in different heights. The border types, which are more suited to the open garden, can grow to 60cm (2ft), while the dwarf-growing types are better for pot or container work. Look for Platycodon grandiflorus ‘Baby Blue’ at just 15-20cm (6-8in) tall, and Platycodon grandiflorus var. Mariesii at around 25cm (10in).
You can grow plants from seed, sown in Spring, but the plants can take a full year to reach flowering size; alternatively, buy established plants for immediate use.
This hardy perennial is fully frost-hardy, surviving better over Winter in the open garden than in pots or baskets. Houseplants should be kept as cool as possible to prolong the flowering period. Seed can be surface-sown in Spring; provide a temperature of around 21°C (70°F). Theare fragile and should be handled carefully.
Grow this plant outside in full sun; plants indoors welcome a respite from direct sunlight, but still need good, bright light.
Water the Balloon Flower thoroughly, then wait for the surface of theto begin to dry out before giving the next thorough watering; keep drier in Winter.
Platycodon grandiflorus has no need of any additional humidity; the closely-packed stems will rot if any excess water accumulates among them.
Give the Balloon Flower a feed every two weeks during the plant’s growing period, using a proprietary fertilizer.
Repot this plant as and when necessary: as the Balloon Flower is fragile, repot the dormant plant in Winter, using a loam-based compost. Other plants for Summer colour can be added carefully later.
Dwarf plants in bud are available as cool-house plants from June to October, or for use in window-boxes. Combine the dwarf Balloon Flower with trailing Lobelia and Baby Blue Eyes (Nemophila) for a pretty Summer display of white and blue, and add a couple of Spider Plants (Chlorophytum) to provide additional height.
Very hot conditions indoors will limit the life span of the flowers.
Aphids may attack plants outside: use a suitable insecticide as soon as the problem, is noticed.