This is a Platycodon, but the common name is “Balloon flower.” Pretty appropriate, isn’t it? From the family ‘Campanulaceae,’ they’re also known as Chinese Bellflowers. Originating from China, Japan, and Eastern Siberia, Platycodons are clump forming, long-lived perennials that flower throughout summer. They thrive in full sun, but also do well in partial shade (mine are in partial shade). I think the purple one is a Platycodon grandiflorous. I have several of them in my front yard garden and they bloom in both purple-blue and white with purple splotches and streaks. Some species of Playtcodon self-seed (mine certainly has).
It is named “Balloon flower” because the flower buds puff up like balloons before opening outward into upward-facing, bell-shaped flowers with five pointed lobes. There is another type of Balloon flower with blue buds that never burst open (remaining balloon-shaped). Hmmmm…methinks I must find one of these and add it to this “organized chaos” of a garden of mine. This link offers information on Balloon flowers and seed-starting instructions as well.
Several plant nurseries sell them online. I’ve ordered other plants from Spring Hill and have had good luck with their inventory. They sell a mixture of Balloon Flowers in a “buy three, get three free” scenario. White Flower Farm sells a beautiful double flowering one (hmmm…shouldn’t I have one of these, too?).
UPDATE: Check out this interesting information about platycodons on the Bookish Gardener’s site!
© Cindy Dyer. All rights reserved.

Ah, the lovely balloon flowers. Very pretty – I’ve never seen a purple/white one before. I have Marie’s Balloonflowers in my perennial garden – all foliage yet, no blooms for a few more weeks I’m guessing.
I have one that has both splotchy and purple blooms on it. I transplanted last summer when I moved to a new house, it promptly died back, but now is back up and looking as good as ever. It’s a cool plant, all around, for sure!