Balloon flower Platycodon grandiflorus 'Astra Blue' (Astra Series)

👤 Non-toxic to humans
🐾 Non-toxic to pets
🌸 Blooming
🍪 Edible
‍🌱 Easy-care
balloon flower 'Astra Blue'


Commonly known as balloon flower, 'Astra Blue' is recognized for its distinct flower buds which resemble little balloons before they burst open into star-shaped blossoms. The flowers are a vivid blue color, adding a pop of brightness to any garden setting. The foliage is made up of lance-shaped leaves that are a rich green, creating a lovely backdrop for the showy flowers that bloom from early to late summer. The plant has a bushy habit, with multiple stems rising from the base that bear both the lush leaves and the enchanting flowers. Balloon flower 'Astra Blue' contributes a touch of whimsy and charm to the landscape with its unique bud shape and striking blue petals that attract both visual attention and visiting pollinators like bees and butterflies.

Plant Info
Common Problems

About this plant

  • memoNames

    • Family


    • Synonyms

      Balloon Flower, Chinese Bellflower, Japanese Bellflower.

    • Common names

      Platycodon grandiflorus, Campanula grandiflora, Platycodon sinensis, Campanula glauca.

  • skullToxicity

    • To humans

      The balloon flower (Platycodon grandiflorus) is generally not considered to be toxic to humans. Most sources suggest that this plant does not contain significant levels of toxic compounds, and accidental ingestion typically doesn't lead to severe poisoning. However, as with any non-food plant, sensitivity or allergic reactions may occur in some individuals. If someone were to have a sensitivity to the plant, they might experience mild gastrointestinal upset. It's always a good practice to avoid eating ornamental plants as they are not intended for consumption and could be treated with pesticides or other chemicals harmful to humans.

    • To pets

      The balloon flower is not known to be toxic to pets such as dogs and cats. This plant is generally considered safe around animals, and ingestion should not cause serious harm. However, as with humans, digestive upset can occur if a pet eats a significant quantity of non-food plants due to the digestive system reacting to unfamiliar plant matter. If a pet consumes any part of the balloon flower and exhibits symptoms of distress, it is advisable to consult a veterinarian.

  • infoCharacteristics

    • Life cycle


    • Foliage type


    • Color of leaves


    • Flower color


    • Height

      1-2 feet (30-60 cm)

    • Spread

      1 foot (30 cm)

    • Plant type


    • Hardiness zones


    • Native area

      East Asia


  • money-bagGeneral Benefits

    • Easy to Grow: Balloon Flower is known for being easy to cultivate, making it suitable for gardeners with different levels of experience.
    • Attracts Pollinators: The vibrant blue flowers attract bees, butterflies, and other pollinators to the garden, promoting biodiversity.
    • Drought Tolerance: Once established, Balloon Flower can tolerate periods of drought, reducing the need for frequent watering.
    • Long Blooming Period: It offers a long blooming period from summer to early fall, providing extended visual interest in the garden.
    • Cold Hardy: Balloon Flower is resilient in cold temperatures and can survive in USDA hardiness zones 3 to 8, making it versatile for various climates.
    • Compact Size: The 'Astra Blue' variety is compact, which is ideal for small gardens, borders, containers, or even as a houseplant.
    • Unique Flower Shape: The balloon-like buds and star-shaped flowers add unique textures and shapes to a garden display.
    • Low Maintenance: Balloon Flower is low maintenance, requiring minimal care once it's been established in the garden.
    • Deer and Rabbit Resistant: It is generally resistant to deer and rabbits, which helps prevent damage from these animals.

  • medicalMedical Properties

    • Anti-inflammatory: Platycodon grandiflorus, commonly known as balloon flower, has been used for its anti-inflammatory properties.
    • Expectorant: It is traditionally used to clear mucus and may work as an expectorant.
    • Throat soothing: The root of the balloon flower is known to soothe a sore throat.
    • Immune support: Some preparations of the plant are believed to bolster the immune system.

  • windAir-purifying Qualities

    This plant is not specifically known for air purifying qualities.

  • leavesOther Uses

    • As a natural dye: The blue-violet flowers of the balloon flower can be used to impart color to fabrics and textiles when processed correctly.
    • In soap making: The petals can be incorporated into homemade soaps for decorative purposes as well as for their potential mild astringent effects.
    • As edible cake decorations: The fresh or candied flowers of the balloon flower can be used to embellish desserts, adding an elegant and edible flair.
    • In floral arrangements: The striking shape and color of the balloon flower make it a unique addition to both fresh and dried floral arrangements.
    • As a teaching tool: The plant's unique balloon-like buds can be used to demonstrate plant development and morphology in educational settings.
    • In balloon flower festivals: In some regions, the balloon flower is celebrated and showcased in festivals, focusing on the cultural and aesthetic value of the plant.
    • As craft material: Dried flowers can be incorporated into homemade paper or used in various arts and crafts projects, such as pressing into picture frames or making bookmarks.
    • In photography: Due to their distinctive and photogenic blooms, balloon flowers are often used as subjects in botanical and artistic photography.
    • As a natural confetti: The petals, being biodegradable, can be used as a natural confetti alternative for celebrations.
    • In mixed perennial gardens: Apart from aesthetic value, the balloon flower's deep root system can help improve soil structure and integrity in garden beds.

Interesting Facts

  • bedFeng Shui

    The Balloon Flower is not used in Feng Shui practice.

  • aquariusZodiac Sign Compitability

    The Balloon Flower is not used in astrology practice.

  • spiralPlant Symbolism

    • Enduring Love and Affection - Platycodon grandiflorus, commonly known as Balloon Flower, often symbolizes enduring love due to its ability to withstand various conditions and its hardy nature.
    • Perseverance and Determination - The Balloon Flower's growth habit of breaking through tough soil can represent overcoming obstacles and remaining steadfast in adversity.
    • Unfading Beauty - With its striking blue petals, the Balloon Flower is also seen as a symbol of everlasting and ageless beauty.
    • Honesty and Openness - The flower's unique balloon-like buds that burst open into star-shaped blooms can symbolize honesty and the revelation of one's true sentiments.

Every 1-2 weeks
2500 - 10000 Lux
Every 2-3 years
Spring to Summer
As needed
  • water dropWater

    Balloon flowers should be watered deeply to encourage root growth, providing about 1 inch of water weekly. They are drought-tolerant once established, so it's important to allow the soil to dry out between waterings. Overwatering can lead to root rot; hence, watering should be reduced during the fall and winter months. For potted balloon flowers, ensure the pot has drainage holes and water until the excess just starts to escape from the bottom.

  • sunLight

    Balloon flowers thrive in full sun to partial shade. The ideal location offers morning sunlight and afternoon shade, especially in areas with hot summers. They can tolerate some shade, but too little light may result in fewer blooms and a leggy plant.

  • thermometerTemperature

    Balloon flowers prefer temperate climates and do well in temperatures between 60°F and 80°F. They are hardy from USDA zones 3 through 8, able to withstand temperatures as low as -40°F. Extreme heat above 90°F can stress the plant, so providing some shade during the hottest part of the day is beneficial.

  • scissorsPruning

    Prune balloon flowers to remove spent blooms and encourage a second flush of flowers. Deadheading regularly improves the plant's appearance and vigor. Cut back the stems to the ground level in late fall or early spring, as this promotes healthy growth and prevents overcrowding.

  • broomCleaning

    As needed

  • bambooSoil

    Balloon Flower thrives in well-draining soil with a mix of loam, compost, and perlite. The best pH for this plant ranges from slightly acidic to neutral, approximately 5.8 to 7.2.

  • plantRepotting

    Balloon Flower should be repotted every 2-3 years to refresh the soil and accommodate root growth, preferably in the spring as new growth begins.

  • water dropsHumidity & Misting

    Balloon Flower prefers moderate humidity levels but is quite adaptable and can tolerate the humidity levels typically found in home environments.

  • pinSuitable locations

    • Indoor

      Place Balloon Flower in bright, indirect light and ensure good air flow.

    • Outdoor

      Plant in full sun to part shade, rich soil, space 12 inches apart.

    • Hardiness zone

      3-9 USDA

  • circleLife cycle

    Platycodon grandiflorus 'Astra Blue', commonly known as balloon flower, begins its life cycle as a seed sown in late winter or early spring. Upon germination, the seedling emerges and develops into a small rosette of foliage, gradually forming a thick, fleshy root system. As the plant matures, stems elongate, and distinctive flower buds that resemble hot air balloons form, eventually blooming into star-shaped blue flowers by mid to late summer. After pollination, typically by insects, these flowers produce seed capsules that ripen and release seeds for the next generation. In fall, the above-ground parts of the plant die back, while the root system goes dormant over winter. With the arrival of spring, the plant regrows from its perennial roots, repeating the cycle.

  • sproutPropogation

    • Propogation time

      Spring to Summer

    • The most popular method of propagating Balloon Flower 'Astra Blue' is through seed sowing. They can be started indoors 6-8 weeks before the last frost date or directly sown into the garden after the danger of frost has passed. The seeds should be lightly pressed into the soil but not covered, as they need light to germinate effectively. Keep the soil consistently moist and at a temperature of around 70°F (21°C). Germination usually takes 14-30 days. Once the seedlings have developed their first true leaves and are large enough to handle, they can be transplanted into individual pots or spaced in the garden. It's key to handle Balloon Flower roots carefully as they do not like to be disturbed.