Gardening Plants & Flowers Perennials

How to Grow and Care for Million Bells

million bells

The Spruce / Autumn Wood 

Million bells, also known as Calibrachoa and mini petunia, is a perennial, flowering plant that is often grown as an annual, blooming nonstop from spring to frost without the need for deadheading. These flowers thrive in warm climates, preferring full sun and moist, well-draining soils, and look spectacular in hanging baskets.

Common Name Million bells, Calibrachoa, mini petunia
Botanical Name Calibrachoa x hybrida
Plant Type Perennial, herbaceous
Mature Size 3-9 in. tall, 6-24 in. wide
Sun Exposure Full, partial
Soil Type Loamy, silt, moist but well-drained
Soil pH Neutral, acidic
Bloom Time Spring, summer, fall
Flower Color yellow, orange, purple, red
Hardiness Zones 7-11 (USDA)
Native Area South America, Central America

Million Bells Care

Million bells plants make excellent ground cover in perennial regions, in addition to their popular use as annuals in baskets. Here are the main care requirements for million bells:

  • Choose a sunny spot, ideally getting six hours of sunlight per day, though partial shade is also acceptable.
  • Prepare organically-rich soil that holds moisture but is still well-draining.
  • Water regularly to keep the soil evenly moist and do not let it dry out completely.
  • Fertilize regularly during the growing season.
million bells
The Spruce / Autumn Wood
million bells in a hanging container
The Spruce / Autumn Wood 
multi-colored million bells
Hidestugu Mori / Getty Images

Light

Million bells flowers grow best in full sun. Dappled shade or afternoon shade are second-choice placements in the garden, but this might turn your “million bells” into “hundred bells” due to a reduction in blooming.

Soil

Fill your planting containers with soilless potting mix amended with humus or compost. Potting mix will ensure the excellent drainage necessary for plant health, as million bells hates soggy soil.

If you are growing the plants in the ground, plant them in rich, well-draining soil with a slightly acidic pH of 5.2 to 6. Space the plants about 18 inches apart to allow for spreading. Cover the soil with organic mulch to keep the root system cool and to stop evaporation.

Water

Keep the plants evenly moist, and don't ever let the soil completely dry out. Do a "swing test" daily if you have hanging baskets: Does the basket seem light when you give it a push? If so, you must irrigate until water flows through the drainage holes. If you're using pots or other containers, test the soil moisture by inserting your finger up to the second knuckle. If the soil at your fingertip feels dry, it's time to water. Add water until it comes out of the container's drainage holes. And continue to test the soil regularly to keep on top of watering needs.

Temperature and Humidity

Million bells plants thrive in warm weather, but they can become heat-stressed. If you live in a dry climate, you can try misting the plants daily or as needed to increase humidity and revive the foliage. But do not mist in direct sunlight, which can lead to leaf burn.

Fertilizer

Fertilize your million bells every two weeks throughout the growing season with a liquid flower fertilizer, which provides nutrients more quickly than time-release formulas. This is especially important at summer's end to coax more blooms out of the plants. If your million bells plants have light green or yellowish foliage, this is also a symptom that they need a nutrient boost (or more sunshine). 

Types of Million Bells

Million bells is the most well-known hybrid in the Calibrachoa genus. Within this group, there are many varieties and colors to choose from, including:

  • 'Kabloom': Flowers available in pink, white, red, yellow, and deep blue
  • 'Crackling Fire': Dark neon orange flowers marbled with yellow
  • 'Tangerine': Cheerful clear orange flowers with red veining
  • 'Terra Cotta': Yellow flecked with red
  • 'Trailing Sky Blue': Bright lavender-blue flowers with green throats
  • 'Cherry Pink': Hot pink flowers with yellow throats; a hummingbird beacon

Pruning

In order to keep million bells plants bushy, pinch or cut back the tips, which will cause the plant to put out more branches. You can cut the plant back significantly in a hanging basket if it has become leggy, especially when there's lots of time left in the growing season.

Propagating Million Bells

Million bells is most easily propagated by cuttings, ideally during the growing season. In order to start a new plant from a cutting:

  1. Remove a stem without any flowers, removing the leaves from the bottom few inches.
  2. Place the cutting in water.
  3. Wait until you see roots forming, which could take about a month.
  4. Place the rooted cutting in fresh, well-draining soil.
  5. Keep a close eye on the cutting as it's becoming established.

Common Pests & Plant Diseases

If you plant your million bells too early in the spring, they might fall prey to aphids. To prevent this, plant them outdoors around the same time you'd plant tomatoes in your area.

Whether they're grown in containers or in the ground, keep your plants from becoming heat-stressed, which can tempt spider mites. If the weather conditions are dry and dusty, practice cultural control of these pests by misting plants with water daily.

Furthermore, unlike petunias, million bells don’t suffer from the dreaded tobacco budworm. 

How to Get Million Bells to Bloom

Million bells should flower prolifically when healthy and grown in the proper conditions. Though these plants can survive in partial sunlight, they really prefer full sun. So if your million bells isn't blooming properly, make sure it's getting at least six hours of sunlight per day or, ideally, even more.

Bloom Months

Million bells typically blooms from May until October or until the first frost.

How Long Does Million Bells Bloom?

Million bells will bloom from late spring and well into fall. You can make them bloom for even longer by protecting them from the first few frosts of the season, by covering in-ground plants or bringing baskets inside at night.

When grown as perennials, they will bloom year after year in good health.

How to Encourage More Blooms

Give million bells ample sunlight, protect their soil from drying out, and fertilize regularly to encourage as many blooms as possible.

Deadheading Million Blooms

Deadheading million bells flowers is totally unnecessary. These plants are considered "self-cleaning" and will continue to bloom readily without deadheading. You may want to pinch back long stems as plants in hanging baskets get leggy towards the end of the growing season to sustain bushiness.

FAQ
  • Do million bells come back every year?

    Million bells are perennial to USDA zones 7-11, where they will come back year after year. However, they are commonly sold and grown in other zones as annuals, where they will not come back and will need to be repurchased.

  • Are million bells the same as petunias?

    No, while they look similar, million bells and petunias are totally different plants, each in a separate genus: Calibrachoa and Petunia, respectively.

  • Do hummingbirds like million bells?

    Yes, million bells plants are known for attracting hummingbirds, especially when grown in hanging baskets.