Campanulaceae offers splendid variety

As a flower gardener, I've been a little lost in the Campanulaceae family, with its bellflowers, balloon flowers and ladybells. With approximately 2,400 species in the 80-plus genera on the family tree — or, should I say, family herbaceous plant — it's no small group of bloomers to consider.

For starters, balloon flower, Platycodon grandiflorus, is the sole member in its genus. It is sometimes called Chinese bellflower, which certainly has lent to my confusion because bellflower is the common name of choice for the members of the much larger Campanula genus.

What's special about balloon flower is that its purple, blue, pink or white blooms puff up like Jiffy Pop popcorn bags before bursting open into upward-facing, five-petalled bells. Though they no longer reside in my flowerbeds, they did when my sons were small. They were a source of fascination for the two little boys who, as they raced by, would stop to give the about-to-burst-open blooms a squeeze to help them along.

Balloon flower, native to Siberia, China, Korea and Japan, is a clump-forming perennial that can reach heights of 40 inches with 3-inch blooms that puff up all summer long, especially if dead-headed. Plants can be a little floppy, but a number of cultivars have been developed that add height options and more bloom color choices.

Perhaps the best known of the ladybells branch of the family are Adenophora liliifolia and A. stricta, the latter also known as A. farreri and A. confusa. All feature a pretty 2- to 3-foot tall spike of five-petalled pale purple-blue dangling bells. Some more tidy gardeners find these species spread themselves around a little too freely.

The 40-ish species of Adenophora are native to eastern Asia and Europe, and the difference between ladybells and the 250-ish species of Campanulas, or bellflowers, is internal structure as ladybells have a sort of cuplike disk that covers plants' lady parts.

Honestly, I can't tell the difference between the aforementioned ladybells, also known as false campanula, and one of the most common bellflowers, C. rapunculoides, which until recently held down a corner of one of my flowerbeds for many years.

Because they can spread both below the ground by rhizome and on top of the soil by seed, it's good to keep an eye on bellflowers (and ladybells) wherever you plant them. A hand trowel and a little vigilance can keep them contained, well worth the effort, as there are several bed-worthy bellflowers.

The already mentioned C. rapunculoides is also known as creeping bellflower and rover bellflower. These old-fashioned wanderers grow to 3 feet with pale violet-blue dangling bells. They were actually choked out of their spot by some rogue tawny daylilies that I am having far more trouble managing.

Another species that has reliably grown where I've allowed it to spread is C. glomerata, or clustered bellflower. It has an entirely different growth habit. Reaching a height of only about 18 inches, its upward-facing, darker purple-blue blooms grow in clusters, rather than singly, forming a plump ball of blooms on the top of each flower stem. Smaller clusters appear down the stem and the terminal clusters can be made up of up to a dozen blooms.

Clustered bellflower can be found throughout Europe and parts of Asia where it has naturalized.

The most recent bellflower addition to my gardens is a hybrid cross between C. takesimana, Korean bellflower, and C. punctata, spotted bellflower. Both parent plants' blooms are most commonly pink. The petals of the flowers don't spread apart like many other bellflowers but separate only at the ends. This shape lends itself to the plant's common name in Korea: lantern flower.

Both parent plants are lovely, but I am crazy about their weird and wonderful offspring C. "Pink Octopus," planted two years ago in one of my flowerbeds. Terra Nova Nurseries filed this cultivar in 2006, so it has only been available for a short time.

Octopus' five petals are narrow and separated clear to the base of the bloom. The petals are purple-pink on the outside, and the insides are spotted with a slightly darker color. These unusual and striking plants have grown only to about 10 inches in height.

At least one variety of bellflower is native to Missouri: the sweet little C. rotundifolia, also known by the charming name of harebell. Indigenous plants always are a good choice.