How to Grow Million Bells: Your Guide to Trailing Petunias

Million Bells bloom in multiple colors in a hanging basket
Photo Credit
Aprilflowers
Botanical Name
Calibrachoa
Plant Type
Sun Exposure
Bloom Time
Hardiness Zone

Also receive the Almanac Daily newsletter including gardening tips, weather, astronomical events, and more.

No content available.
Subhead

Planting, Growing, and Caring for Million Bells

Print Friendly and PDF

Million Bells, a vibrant and prolific flowering plant, is a popular choice for hanging baskets and containers. Known for its abundance of small, colorful blooms, this trailing beauty adds a splash of color to any outdoor space. Learn how to grow Million Bells. With proper care, this plant will reward you with nonstop blooms throughout the growing season.

About Million Bells

Ring out! Commonly referred to by its trademarked name ‘Million Bells’ and also sometimes known as “mini petunia” for its abundance of 1-inch-wide blooms and resemblance to that annual, trailing petunia belongs to the Calibrachoa— not Petunia—genus. If given the attention it needs, this plant will pour forth hundreds of colorful flowers on stems up to 30 inches long from spring to first frost. The colors of its blooms range from blue, bronze, magenta, pink, and red to violet, white, and yellow. The plant is well suited for hanging baskets and containers.

Nate Dalman of the West Central Research and Outreach Center says, “They are a fairly new ornamental, introduced in the 1990s, and rapidly gained popularity with the gardening world.”

Million Bells is a tender perennial that is winter-hardy in Zones 9 to 11 and treated as an annual elsewhere.
 

Calibrachoa or bell flower, Flower of a cultivated Million bell, Calibrachoa x hybrid
Photo: ElenaNoeva

Planting

Million Bells are hybrid plants that produce few to no seeds. Purchasing plants or growing cuttings vegetatively (from an existing plant, unless such propagation is prohibited by trademark law) is recommended. Take a 6-inch cutting that is flower-free and remove the leaves from the bottom half. Dip the cut end in rooting hormone and plant in potting mix. Provide bright light and warm temperatures (about 70°F) and keep the soil consistently moist; roots should develop in 2 to 4 weeks.

When planting purchased plants or transplanting cuttings, provide potting mix amended with compost and/or
aged manure and peat moss (if desired). If using potting mix that does not contain fertilizer, add in a slow-release formula at the time of planting. A pH of from 5.0 to 6.5 is crucial: This plant will not thrive in soil with a pH that is outside this range.

Move outdoors when the threat of frost has passed.

Growing

Million Bells require full sun (at least 6 hours per day); while they tolerate light shade, their production diminishes as shade increases.

Water regularly to keep the soil moist but not soggy. Trailing petunia is somewhat drought-tolerant but check it often in hot, dry weather by pushing a finger 1 inch into the soil: If it is dry, water enough to be damp to moist. Between waterings, allow the soil to dry out. Wilting can be a sign of root rot, caused by overwatering.

Fertilize every 2 weeks with a balanced product.

Pinch back tips to encourage branching and flowers. Deadheading is not necessary, as Million Bells cleans itself. In midseason, if desired, encourage new growth/rejuvenation by cutting back branches.

Purple Million bells, Calibrachoa, a popular outdoor container plant in hanging basket, closeup with selective focus
Photo: mcajan
Gardening Products

Wit and Wisdom

Pests/Diseases

Diseases: black root rot, powdery mildew, viruses. 

Pests: aphids, spider mites.

About The Author

Jennifer Keating

Jennifer is the Digital Editor at The Old Farmer’s Almanac. She is an active equestrian and spends much of her free time at the barn. When she’s not riding, she loves caring for her collection of house plants, baking, and playing in her gardens. Read More from Jennifer Keating