This Balloon Flower (Platycodon species) appears to be a double or semi-double pink variety, but Richard couldn't recall the variety and for the life of us, we can't trace it down. Balloon Flowers are named for the shape of their buds, which open into beautiful star-shaped flowers. Perennials, they like sun or partial shade, usually grow to 2 or 3 feet tall, bloom all season long, and make excellent container plants and cut flowers.