Description

Platycodon grandiflorus
Platycodon grandiflorus

Perennial. Star-shaped blue flowers, 7 cm in diameter, on small plants 20 to 30 cm high. Shoots, flower buds and young leaves are edible. Flowering in August and September. Can flower the first year with early sowing. Also known as balloon flower. Hardiness Zone 3.

Full sun to part shade. Well-drained, rich soil. Sow indoors 8 to 10 weeks before last frost. 1 mm deep, 30 cm between plants. Slow germination, 15-30 days at 18-22°C. Contrasting temperatures, warm during the day and cooler at night, can stimulate germination.

Germination: 40% in January 2026
Ecological seeds produced at Catherine’s Ornamental Garden.

Note
Our seeds come from Platycodon Sentimental Blue, a selection of dwarf plants that rarely exceed 30 cm in height. We’ve been growing and propagating it in our gardens since 2011. We always hoped to achieve a better germination rate. In 2026, after 15 years, we said to ourselves, “Oh boy! This is going to be it!”

It’s a beautiful, long-lasting little perennial that requires little maintenance. Plants are slow to get going in spring, so be sure to indicate where they are to be planted.