Calibrachoa Plants: How to Grow Million Bells

Calibrachoa, known by the common name million bells, is an herbaceous perennial or annual native to South America that blooms in a variety of flower colors (from pink and orange to white). They have dark green foliage and trumpet-shaped blooms that feature lines down their petals, similar to a begonia or petunia flower.

Calibrachoas have a trailing habit, and they spread quickly to spill over the sides of a growing container, making them popular to grow in window boxes and hanging baskets. It is also a popular choice for ornamental ground cover if you plant it directly in your garden. Calibrachoa plants are prolific bloomers that flower multiple times throughout the growing season, attracting helpful pollinators like hummingbirds and butterflies.

Calibrachoa is a hybrid plant that gardeners cross-breed ubiquitously to create a number of varieties that suit their preferences. Here are some of the most popular varieties of calibrachoa plants.

1. 1. MiniFamous double amethyst: These annuals bloom stunning violet and magenta flowers that have a double-petaled effect. They are a popular choice to plant in hanging baskets because of the way they spill over the edge.
2. 2. Cabaret deep yellow: This heat-tolerant Calibrachoa cultivar attracts butterflies, bees, and hummingbirds with its dense coverage of yellow flowers.
3. 3. Superbells dreamsicle: Superbells dreamsicle calibrachoa blooms showy, deep orange flowers throughout its warm growing season and needs full sun to partial shade to thrive.
4. 4. Callie apricot: Callie apricot is another variety that is perfect for hanging baskets because of its trailing growth habit. It blooms with an abundance of apricot-colored flowers.
5. 5. Kabloom white: Gardeners who love neutral flowers will love kabloom white calibrachoa, which has stunning white flowers with yellow-edged petals. This variety is both drought- and heat-resistant.

Plant your million bells calibrachoa plants in early spring or in fall if you’re planting them outside, or year-round if you’re growing them as indoor container plants. Spring-planted calibrachoa plants will benefit from the heat as the soil warms up in summer, encouraging the plant’s root and foliage growth. Your calibrachoa plants should start to bloom by late spring. If you plant calibrachoa in the fall, mulch the soil around your new plants to protect their root systems from frost. Keep in mind that these frost-tender perennials grow well in USDA hardiness zones nine to eleven and will not tolerate a cold winter.

You can grow calibrachoa from an established plant bought from a nursery or garden center, or from seeds that you buy. Follow this simple tutorial for planting calibrachoa from seed.

1. 1. Sow seeds in a seed tray. Sow your calibrachoa seeds in a seed tray roughly eight weeks before you want to plant them in their final growing spot. Lay your seeds on the surface of a slightly acidic to neutral potting soil and mist it lightly with water. Leave your seed tray in a warm place.
2. 2. Care for your seedlings. You should see sprouts within ten to fourteen days. Move the seed tray to a location that receives sunlight, like a window sill, once your seeds have become seedlings.
3. 3. Thin your seedlings to one per cell. Thin out the seedlings so that you have only one sprout per cell in your seed tray. Do this once your seedlings develop two leaves each. Continue to mist your seedlings with water and give them lots of sunlight.
4. 4. Plant in your garden or a container. Move your seedlings into the garden after eight weeks of growing, as long as the last frost has passed. Plant your seedlings in a container such as a hanging basket or terra cotta pot filled with organic soil or directly in the garden. Remember that calibrachoas are fast-spreading plants, so give them a lot of space in your garden.

Functioning both outdoors and as houseplants, million bells flowers are typically low-maintenance, but there are a few things you can do to help them thrive. Follow these calibrachoa care tips as your plants establish themselves.

• Deadheading: Calibrachoa plants are “self-cleaning” plants, meaning that they shed their dying blooms without the need to deadhead—or remove spent blooms to redirect the plant’s energy. Cut calibrachoa back at the end of the summer to promote new growth for the following growing season.
• Soil: Calibrachoa plants need well-draining soil. Make sure your planting container has drainage holes, and that your soil doesn’t become too compacted to avoid root rot. Calibrachoa is also susceptible to becoming root-bound if you grow it in a container. Check your plants and prune back roots if your plant becomes root-bound.
• Pests: Calibrachoa plants are susceptible to aphid infestations. Treat your plants with neem oil to keep aphids away. You can also use a mixture of water and dishwashing detergent to spray aphids off of your plants.
• Fertilizing: Feed your million bells plants with a slow-release liquid fertilizer every two weeks, particularly during the end of the growing season, to encourage one last bloom time before the winter.

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