You know these plants will bring fun and whimsy to your flowerbeds or container garden with the common name balloon flowers! Before the buds open on the plants, they look like miniature bluish-purple, pink, or white hot air balloons. These whimsical buds are fun for kids and adults to pop with their fingers.
Balloon flowers are low-maintenance plants with few pest problems, making them a great addition to your garden. Read through this article for all the information you need for growing balloon flowers yourself!
Also called Chinese bellflower or Japanese bellflower, these beautiful little perennials are native to eastern Asia (Korea, China, and Japan) and the far east region of Russia (Siberia). The flower buds puff up like hot air balloons and open into flowers with five petals to create a star-shaped blossom. They are great for attracting pollinators like bees and butterflies to your landscape.
Types of Balloon Flowers
Balloon flowers have only one species (Platycodon grandiflorus), but numerous cultivars are available. Different varieties have been bred for varying colors and blooms. Sometimes these plants are incorrectly called by the botanical name Platycodon grandiflorum; this, however, is the scientific name for doraji root, which is commonly used in Chinese medicine.
The ten cultivars include:
- Apoyama: violet flowers
- Apoyama Misato Purple: dark purple flowers, dwarf variety
- Double Blue: two whorls of bluish-purple flowers
- Fairy Snow: white flowers with slightly blue veins
- Fuji Blue: bluish-purple flowers that are almost transparent
- Hakone Double Blue: double bluish-purple flowers that grow in clusters
- Hakone Double White: double white flowers that grow in clusters
- Komachi: dark blue buds stayed closed and never open
- Mother of Pearl: pale pink flowers with slightly darker veins in the petals
- Sentimental Blue: light blue flowers, dwarf variety
These perennial plants like slightly cooler temperatures and are recommended for North America in USDA growing zones 3 to 8. They will survive in the somewhat warmer zone 9 if they get a reprieve from the heat; the best way to do this is to plant them where they can get some afternoon shade.
Starting Balloon Flowers
You can start balloon flower plants from seed by taking cuttings from established plants or dividing larger plants into smaller clumps. Starting from seed is the most successful method, and it isn’t necessary to purchase seeds if you have access to a plant. It’s pretty easy to collect seeds from a flowering plant.
Starting new plants from seed is the preferred method, with the seeds being sown directly into the garden soil or potting media if you are growing them in containers. You can start seeds indoors, but they don’t always transplant well—they develop a long taproot that doesn’t like to be disturbed or moved.
After the purple-blue flowers fade and the petals fall off the plant stems, you will see a brown seed pod. Once the stem and pod dry out completely, snap the pod off the stem and dry it in a brown paper bag. After dried, crack the seed pod open to reveal the tiny brown seeds resembling rice grains.
Propagating Via Cuttings
Cuttings aren’t a popular method as they are slow to develop roots and often perish before the roots form. Use a pair of sharp, disinfected pruners to cut off a four-inch piece of a stem. Remove the foliage from the bottom two inches so it is bare. Then dip the cut end in rooting hormone and plant it in a growing medium.
If you choose to divide plants, do so in the spring. The best timing is just after the plant starts sending up new stems but before bloom time. Dig out the clump, removing 12-inches of soil outward from the plant to avoid damaging the roots. Split the cluster in half and then plant both divisions.
Planting Balloon Flowers
As perennials, balloon flower plants don’t begin actively growing for the season until the temperatures warm in the spring. So it’s critical to time planting for the spring to coincide with this natural growth cycle. When direct sowing seeds, wait until all chance of frost has passed. Divide plants and take cuttings once stems are at least six inches long.
Soil Requirements and Prep
Garden plants prefer rich soil with a slightly acidic soil pH and good drainage. They do best when planted in loam or sandy loam but tolerate everything but heavy clay. Before planting, mix two or three inches of fully decomposed manure or finished compost into the garden bed to improve the soil structure, drainage, and organic matter.
Since balloon flowers are short and don’t grow very wide, you can plant them relatively close together. Space seeds, transplants, or cuttings 8 to 10” apart. This close spacing allows for a beautiful mass planting in your flower beds if you want to create an eye-catching display. When starting seeds, you can always plant extras and thin them.
When direct sowing seeds, they need to be planted very close to the top of the soil surface to germinate. The easiest way to accomplish a very shallow planting is to scatter seeds on the surface and cover them with a scant layer of soil. Or set them on the surface and then gently water them in.
Caring for Balloon Flower Plants
Balloon flowers grow in full sun to part shade. They will be the most robust, with the most blooms, when they get at least 6 to 8 hours of direct sunlight daily. However, since they prefer cooler climates, they benefit from partial shade in warmer zones, especially during the hottest part of the afternoon.
If your area doesn’t get regular rain, give your plants one inch of water a week. They like a lot of moisture, especially when it’s hot, but keep the ground from being constantly saturated. Plants are susceptible to root rot and prefer the soil dry before being watered again.
These plants are not heavy feeders—they don’t produce fruit and don’t grow very tall in a single season—so their fertilizer requirements are low. Once a year in the spring, scratch a granular, slow-release fertilizer into the soil around the plant. Or you can add a few inches of nitrogen-rich compost around its base for organic, slow-release nutrients.
Pest and Disease Management
One of the great things about growing balloon flowers is the plants are relatively disease-resistant and have few insect problems. The plants are also deer resistant once they reach maturity; deer may feed on young leaves. Regularly scout the plants for slugs and snails, as they can be problematic, especially in damp climates.
Tips for Growing Balloon Flowers
- Before the balloon-like buds develop, pinch or prune back growing tips to get a fuller, bushier plant.
- Deadhead spent blooms to promote new growth and more flowers.
- Cover them with a couple of inches of mulch to protect plants over the winter.
- Leave stems on over the winter, so you can see where plants are coming up in the spring. They are slow to start growing.
- They make beautiful cut flower arrangements but lightly single the cut ends with a flame to stop the milky sap from oozing after cutting stems.