Id-Code: PA 432
Family: Campanulaceae
Origin: Japan and China
Special Features: Flower buds which appear inflated (balloon-like) open into double blossoms leaves
History: Introduced by JELITTO PERENNIAL SEEDS in 1995
Colour: White
Natural Flowering Period: June - August
Winter Hardiness Zones: Z3-8
Growth Habit: Compact, upright habit
Foliage: The lanceolate to ovate shaped leaves are arranged very neatly along the stems
Height with Flower: 50 cm (20'')
Spacing between Plants: 40 cm (16'')
Soil Requirement: Well-drained soils, pH 5.5 - 6.8
Location: Full sun to partial shade
Use: Long-lived perennial well-suited with Eryngium 'Blaukappe', Echinacea paradoxa and Penstemon 'Husker Red'
Specialities: Great for the front of the border; suitable for use as a cut flower

Cultural Tips:
Grams per 1000 seeds: 1
Seeds per Gram: 1000
Seeding Recommendation: 2 g / 1000 plants
Sowing Rate: 2 seeds per cell
Plug tray recommended size(s): 128 or 288
Germination: Rapidly germinating (2 to 3 weeks), keep seed in constant moisture (not wet) with temperatures of about +20°C (68°F). The seed must be covered thinly. Keep in cooler conditions after germination occurs. The germination might be slower and more irregular. This poses no problems.

Scheduling:
Best Sowing Dates: Anytime
Sowing to Germination: 2 - 3 weeks
Germination to Transplant: 4 - 6 weeks
Transplanting to Salable Plant: 6 - 8 weeks
Cutting-Back at Transplanting: Cut-back once to keep more compact

Growing On:
Container Size(s): 1-2 plugs per 11/12 cm (4 1/2'')
Vernalization: Some flowering will occur the first year without vernalization, but improved flowering will occur the 2nd year; and 3-10 weeks of cool temperatures might benefit fuller flowering in the first year.
Forcing: There has been no research on 'Hakone White', but an obvious place to experiment - following vernalization - would be raising daytime temperatures to 60° - 65°F (15° - 17°C). Provide 16 hours of continuous lighting. During the short days of winter, provide a night interruption lighting of 4 hours between 10:00 p.m. and 2:00 a.m. Some later flowering species can be forced in 14 - 16 weeks and perhaps sooner at warmer temperatures. Further experiments are warranted with 'Hakone White'.
Fertilization: Medium (150-200 ppm)