How to Grow Million Bells Flowers

Yellow and Pink Million Bells (Calibrachoa) Flowers.

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Million bells is an annual flower that blooms nonstop without the need for deadheading. When grown in containers, it spills gracefully over the sides of the pot or hanging basket but has a dense trailing habit rather than a spindly one. Million bells plants also attract hummingbirds and butterflies to boot.

Your grandmother probably didn’t grow million bells but not because they didn’t exist. Petunias and million bells were exported from South America to Europe in the 1800s. Petunias ruled until 1997 when Proven Winners licensed the up-and-coming million bells from its breeder, Sunstory Ltd. Million bells filled a rainproof, hot weather-loving niche that petunias couldn't. 

Get to Know Million Bells

Genus Calibrachoa, like other members of the plant family Solanaceae, is a tender perennial, but most gardeners treat the spring through frost bloomers as annuals. The blooms of million bells are approximately 1 inch across, and many sport veining or colorful throats that contrast with the primary petal color. Million bells foliage is bright green, oval-shaped, and compact.

Designing With Million Bells

Their trailing habit, low maintenance, and prolific blooms make million bells excellent candidates for containers and hanging baskets. Million bells are also somewhat drought-tolerant, so you can include them in the rock garden, where they will appreciate the sharp drainage conditions. If you use million bells as a ground cover, keep in mind that plants seldom spread more than 2 feet, so plant enough to ensure adequate coverage.

Popular million bells varieties include:

  • Kabloom: Seeds 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

Tools and Supplies You Will Need

The majority of million bells on the market today are hybrid plants that are vegetatively propagated, so you must grow these from plants rather than seed. However, the newer Kabloom series offers gardeners an economical way to grow million bells from seed, with the same self-cleaning habit and prolific blooms of other varieties. The trade-off is a significant waiting period, as it takes about four months from sowing to bloom for these plants. Million bell seeds need light for germination, which takes about two weeks.

  • Million bells plants
  • Planting containers
  • Soil-free potting mix
  • Humus or compost
  • Organic mulch
  • Watering can
  • Liquid flower fertilizer


Choose the Right Time to Plant

Million bells thrive in warm and hot weather. Plan to plant them outdoors around the same time you plant your tomatoes. Plants that are installed too early in the spring may fall prey to aphids. 

Fill Your Containers

Fill your planting containers with soil-free potting mix amended with humus or compost. Potting mix will ensure the excellent drainage necessary for plant health, as million bells hate wet feet.

Plant the Flowers

Space the plants to allow for spreading, about 18 inches apart. Cover the soil with organic mulch to keep the root system cool and to stop evaporation.

Place the Containers

Million bells flowers grow best in full sun, where they will attain a height of 3 to 12 inches and a spread of up to 2 feet. Bright dappled shade or afternoon shade are second choice placements in the garden but may turn your “million bells” into “hundred bells” due to a reduction in blooming.

Check for Watering Needs

Keep the plants evenly moist; the soil surface should not dry out. Do a "swing test" daily if you have hanging baskets: Does the basket seem as light as a feather when you give it a push? If so, you must irrigate until water flows through the drainage holes. If you're using pots or similar containers, test the soil for 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. Test the soil regularly to keep on top of watering needs.

Feed Your Million Bells

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

Protect Your Million Bells

Keep your plants from becoming heat stressed, which tempts spider mites. If your weather conditions are dry and dusty, practice cultural control of these pests by misting plants with water daily. Unlike petunias, million bells don’t suffer from the dreaded tobacco budworm.