How to Grow Balloon Flowers: The Complete Guide

Balloon flower might seem like an unlikely name for a plant with star-shaped blossoms, but they got their name because the buds look like little hot air balloons. If you’re looking for a charming perennial plant that blooms throughout the summer, then the balloon flower is ready to come in for a landing in your garden.

About Balloon Flower

A lovely flower with a history of culinary and medicinal use, balloon flower (Platycodon grandiflorus) is primarily grown for its beauty in the United States. Its other common names—which include Chinese balloon flower and Japanese bellflower—reflect its Asian origins. It often grows wild on mountain slopes and open hills in Korea, Japan, China, and Siberia.

Balloon flower is a member of the Campanulaceae family and is a hardy perennial throughout much of the United States. It can generally be grown in USDA Zones 3 through 8. It reaches 1 to 2 feet tall depending on the cultivar, and the taller varieties sometimes require staking. Balloon flower isn’t a go-getter in terms of early growth in the spring—it takes its time to emerge from the ground. Because of this, it blooms in the summer and not in the spring.

As far as placement, you really can’t go wrong by situating your balloon flowers in rock gardens, in containers, or using them as edging or border plants. They’ll add gentle pops of blue, pink, white, or purple to corners and edges of your garden and who doesn’t love that?!

*Just before they bloom, balloon flower buds look like small hot air balloons. Credit: PastorG*

Planting

For best results with balloon flower, you’ll want to start with seeds. Other methods of propagation like division or stem cuttings just aren’t as effective with balloon flowers, and most experts recommend starting via seed.

When to Plant

Direct sow seeds into garden beds after your last frost date has passed. (Be aware, however, that the plants will be unlikely to flower in the first year if direct-sown outdoors.)
You can also start seeds indoors about 6 weeks before your last frost date and then transplant outdoors later, but balloon flowers can be a bit fussy about being moved, so direct sowing is sometimes more effective.

How to Plant

The seeds are small, so plant them in the same way you would lettuce or carrot seeds—just lightly pressed into the soil with the thinnest dusting of soil covering them.
It’s possible to grow balloon flower from cuttings, but it’s less convenient and success rates are usually lower than growing from seed.
Division doesn’t work well for balloon flower, according to the North Carolina State Extension. Balloon flower has a long taproot that is sensitive to disturbance.
If you’ve started seeds indoors, you can transplant your balloon flower seedlings outdoors after all danger of frost is past, or transplant them into a larger container.
If growing balloon flowers in a container, it will need to be fairly large and deep to accommodate the plant’s long root.
In a garden bed, space your plants 12 inches apart so they have room to grow without obstructing airflow between each other.

Growing

Balloon flower is easy to start from seed and the good news is that it’s even easier to grow!

Full sun is excellent for balloon flower, though a semi-shaded area is OK too. They’ll bloom more with more sun, though—at least 6 hours is best.
You might find that a little afternoon shade is helpful in regions that experience very hot summer days.
Balloon flower enjoys some rich soil to help produce those gorgeous blooms—loamy soil with plenty of compost, but still well-draining.
If you do any type of transplanting, do it very carefully and sparingly because these flowers don’t like having their roots disturbed.
Take care not to overwater, but balloon flowers do need moist soil.
Balloon flowers generally need slightly acidic soil; a pH of approximately 6.0 to 7.0.
It’s important to know that balloon flower doesn’t establish quickly; if planted from direct-sown seed, you probably won’t get blooms the first year.
The upside is that balloon flowers are a long-lived perennial that will give you years of enjoyment.
In addition to being slow to initially establish themselves, existing balloon flower plants are slow to start growing each spring, so you’ll need to be mindful of where they’re planted when working in your garden before they emerge. You don’t want to crush one accidentally!
As the summer wears on, you can deadhead blossoms as they fade. This will prompt your balloon flowers to put out new blooms as the growing season progresses.
As your balloon flowers grow, staking may be necessary to help them support the weight of their own blossoms. This is less of an issue with smaller or dwarf varieties.
If desired, you can cut the plants back partway through the growing season. This might reduce the need to stake.

Types

‘Sentimental Blue’ is a dwarf variety with blue flowers.
‘Astra Blue’ and ‘Astra Pink’ are beautiful dwarf varieties.
‘Double Blue’ is a lovely cultivar with (surprise!) double blooms. Gorgeous!
The ‘Fuji’ series has varieties in pink, white, and blue. These plants are taller and will likely require staking, according to the National Gardening Association.

balloon flowers with double blooms — *Some varieties of balloon flower feature beautiful double blooms with ten petals. Credit: RococoNeko*

Harvesting

Balloon flowers look simply lovely growing in the garden or on your porch, and they make an excellent (though sometimes underutilized) cut flower. They also attract pollinators. In the United States, balloon flowers typically aren’t harvested for any purpose besides cut flowers.

Platycodon grandiflorus is used in traditional Korean cuisine, where the flowers, called doraji, are harvested for their roots (also called doraji).
The roots are said to have a bitter taste and an aroma similar to ginseng.
The dried doraji roots are cut into thin strips and often sautéed during traditional Korean holidays. *Note: Some sources say that the roots and older leaves of P. grandiflorus may be slightly toxic.
Balloon flowers make excellent additions to cut flower arrangements. They look awesome in a vase!
You can also easily harvest and save the seeds of open-pollinated varieties after the balloon flower blossoms have dried and faded away. Tiny black seeds reside inside small brown pods, which can be broken open to access the seeds.

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Pests/Diseases

Deer likely won’t bother your balloon flowers. In fact, the plant is pretty much immune to attacks from most mammals—rabbits, voles, deer—everybody leaves balloon flowers alone. You may see occasional signs of insect pests, such as:

Slugs
Snails
Aphids
Spider mites

Additionally, a few of the most common plant diseases can affect balloon flowers, though in general they’re pretty resistant:

Powdery mildew
Root rot
Fungal leaf spot

Wit and Wisdom

Balloon flower is an herb, and in Chinese medicine, balloon flower has historically been used to treat coughs and colds, but it has also been used to treat hypertension and inflammation, and also used as an antioxidant.
Balloon flowers are one of Japan’s traditional “Seven Flowers of Autumn.”

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About The Author

Samantha Johnson

Samantha Johnson is an award-winning author and gardening expert with over 20 years of experience cultivating heirloom vegetables and sharing her passion for rural living. Read More from Samantha Johnson