Platycodon or Balloon Flower, for those who still garden in the vernacular, was one of the first perennials that I planted in my garden over 17 years ago. It blossoms in an extremely satisfying shade of blue, it is of good height, and English - style gardens benefit greatly from its presence.
This perennial is slow to establish. In the first year it looks scrawny, in the second it grows flimsily but by year three it is impressive. What I like most about it is the rich shade of blue and the velvety texture of its petals. Of course, there are white or pink varieties that are also available, but they cannot satisfy the gardener’s thirst for luscious perennials, as the blue varieties can. The white and pink don’t project and are not as stately looking. Frankly, if white or pink are desired colors for the flower bed, there are other plants that are more effective than these.
However, just because it is stately does not mean that it is neat. It is uncompromisingly a sun worshipping plant. In my urban garden, each season, I find it necessary to gently stake it and gather together all of the stems into a very loose bouquet. Other more naturalistic gardeners allow the stalks to extend horizontally towards the sun and to kneel through the flower beds, to create swathes of blue punctuation wherever they fall.
Whenever I’ve used Platycodon in large garden composition, I found it more effective to plant it, unstaked, in drifts to create cloudlets of blue throughout the flower bed. The rhythm and repetition of both the flower and the color help to create drama and cohesiveness; the blue is enhanced by its own omnipresence. The composition is especially effective when Phlox paniculata is in bloom. Platycodon makes a perfect partner for this family of perennials because in height, volume and color intensity, it is its equal. Its very specific shade of blue makes the Phlox pop.
Nature rewards the Balloon Flower gardener with polite self seeding. Lift the seedlings as soon as they become apparent and plant them in plastic pots, to be interred in the ground until an appropriate home can be found. Or, transplant the seedlings to a spot in the garden where they can be useful in design or composition. However, mature Platycodon should not be transplanted so cavalierly. Here are two reasons why:-
Firstly, it is often impossible to dig up this perennial with its deep tap root intact. Any pieces left behind, will re grow into a new flowering plant. Secondly, Platycodon goes into shock, the moment that it is lifted, and will not revive fully until the following year. Then, it will remain unimpressive for another season. Balloon Flower is one of the few plants that will be more successful when transplanted directly from a pot with the tap root safely encapsulated within a generous clump of potting soil. That is why I have recommended immediately planting new seedlings into pots until their final homes can be determined. Given the trouble that transplanting seedlings creates, most gardeners simply discard them and purchase nursery - potted plants as needed. Only the patient, fastidious gardener will reap the rewards of the seedlings.
Balloon Flower is camera shy. As the reader can observe from the images posted here, this plant photographs well only in extreme close up. In a long shot or from a distance, it is far more beautiful in the real world.
My first blue Platycodon was the species grandiflorus “mariesii”. It has been replaced in most nurseries first with Fuji Blue and then with double-flowered Hakone. All three will grow 50 cm. tall or twenty inches. A shorter variety, Sentimental Blue, is 25 cm. or 10 inches in height. I grow all four varieties but prefer Fuji Blue for its color and petal texture and Hakone for its double flowers.
In spite of its beauty, there are some gardeners who do not appreciate this perennial because they find its straw-colored dead heads, distributed up and down the stalks of the plant, to be unattractive. I solved that problem by gently removing the dead heads, so as not to disturb the newer buds waiting to open. This can be achieved by snapping off the dead heads with two fingers or, by carefully snipping them with a hand pruner. Done on a regular basis, this manicuring encourages the plant to rebloom. As long as autumn weather remains warm, it is possible to extend the flowering of this plant far beyond its official expiry date.
Platycodon is one perennial whose maturation cannot be accelerated and buying it in a large pot is no guarantee that it will look substantial in the garden in the first season. Sometimes large size plants are force - grown to impress the buyer at point of sale. Then, they often deliver lackluster performances until year two or three. However, it is worth the wait. Repeat; it is worth the wait! Platycodon is in its best form, in year three, when it has created a cloud of blue that makes the pinks and yellows in the garden shimmer. That is when it is truly appreciated.
Update: Several readers have enriched this post with their own Platycodon experiences. Please click on the comment option below to read more.