Gardeners are always on the hunt for unusual, easy to care for perennials, especially if they bloom from mid-summer into fall.
To help us in our quest comes Plant Evaluation Notes by Richard Hawke, plant evaluation manager at the Chicago Botanic Garden. Hawke and his group keep meticulous records on perennials, comparing cultivar to cultivar and noting plants’ ornamental traits.
A recent report covers balloon flower (Platycodon grandiflorus), an under used perennial with beautiful star like blooms and, as Hawke wrote, plump, balloon-shaped buds that “almost bed to be popped.”
A native of Asia, balloon flower is celebrated in Japan in autumnal arrangements. Here in the Midwest, most of cultivars bloom from early July to early September. This lovely plant with blue, pink or white flowers also provides fall color ranging from purple to golden leaves. It is winter hardy throughout Indiana.
Among the 18 varieties in the report, most got much taller than plant descriptions indicated. The height and overall weak stems of balloon flower accounted for most of the lower rankings. Twelve, however, received a four-star rating of good.
At the Chicago Botanic Garden, they were grown with minimal fuss to mimic how most gardeners will likely grow the plants. They were not fertilized or treated with pesticides. They were watered as needed and mulched.
Balloon flowers do best in full sun and well-drained soil. They tolerate light shade, but it contributes to weakened or stretched flower stems.
This is a perennial that will look best when deadheaded because the 3-inch wide flowers look a bit drab when allowed to hang on the plant.
Balloon flower is a bit slow to break ground in spring, so Hawke recommends marking the plant so as not to disturb it during seasonal clean chores. Cut back in late fall when the plant looks unattractive.
‘Astra Blue,’ ‘Baby Blue,’ ‘Double Blue,’ ‘Fuji Blue,’ ‘Fuji Pink,’ ‘Fuji White,’ ‘Komachi,’ ‘Perlmutterschale,’ ‘Sentimental Blue’ and ‘Zwerg’ all received four-stars, or good ratings in the trial at the Chicago Botanic Garden.