This compact trailing plant produces masses of fully double blue-purple blooms that resemble miniature roses, creating a rich and elegant display throughout summer. Calibrachoa ‘Callie Double Blue’ is perfect for hanging baskets, patio containers, and window boxes, where its cascading stems spill naturally over the edges in a cloud of colour. Flowering continuously from late spring until the first frosts, it brings long-lasting impact with very little maintenance.
Calibrachoa ‘Callie Double Blue’, commonly known as Million Bells, is loved for its abundant flowering and soft, layered double blooms. The velvety blue-purple flowers add depth and texture to summer displays and pair beautifully with white, silver, or lime-green trailing plants. Compact but vigorous in growth, this variety creates full, lush baskets while remaining neat and easy to manage through the season.
Tender Perennial
Trailing, Basket Plant, Long Flowering
Flowers: Late Spring to First Frosts
Foliage: Spring to Autumn
Scientific Name
Calibrachoa ‘Callie Double Blue’
Synonyms
Often sold simply as Calibrachoa or Million Bells
Common Name
Million Bells, Double Calibrachoa
Origin
Cultivated hybrid originating from South American Calibrachoa species
Pruning Tips
Trim lightly during midsummer if stems become leggy or flowering slows. This encourages bushier growth and a fresh flush of blooms.
Wildlife Value
The nectar-rich flowers can attract bees and other pollinating insects during summer.
Positioning
Best grown in full sun or light partial shade in hanging baskets, patio containers, and window boxes. Prefers a warm, sheltered position for the strongest flowering display.
Water
Water regularly during warm weather, especially in baskets and containers which can dry out quickly. Keep compost evenly moist but avoid soggy conditions.
Soil
Thrives in fertile, free-draining compost rich in organic matter. A quality peat-free basket or container compost is ideal.
Food
Feed every 1–2 weeks with a high-potash liquid fertiliser throughout the growing season to support continuous flowering.
Pet-safe
Generally considered non-toxic to pets, although ingestion may still cause mild stomach upset.
Sprouts Top Tips
The rich blue-purple double blooms look especially lovely paired with white flowers or trailing silver foliage for a softer, elegant summer basket display.
