Calibrachoa, also known, as million bells are one of the most popular plants for growing in containers and it's no wonder why. They look great in hanging baskets, bowls, or mixed containers. They also look fabulous in unusual containers like colanders or even plastic laundry baskets--actually, they look pretty great in anything. They come in a dizzying array of colors—from magenta to purple, to white and everything in between and are a classic spiller plant. They also come in a double bloom that is stunning. Calibrachoa are prolific bloomers and will happily produce smallish blossoms that resemble tiny petunia flowers, from spring to well into fall if given good sun, enough water, and food. They are pretty drought, heat tolerant, and even cold tolerant but to get the best blooms, don’t let them dry out repeatedly.
Care – Calibrachoa are not hard to care for, but there are a few things to know to keep them blooming from spring through summer and well into fall. They like full sun but will tolerate some shade. They like, fast-draining potting soil and make sure your pot has good drainage because they don’t like to be kept too wet. To keep them well hydrated, but not water-logged, add water after the top inch or so of the soil dries out. To check if your plant needs water, stick your finger into the soil up to the second knuckle. If the soil feels dry at your fingertip, water deeply, adding water until it drains out of the bottom of your pot. Don’t water again until the soil dries, testing as above. However, there's a catch--how fast your soil will dry out depends on several factors and those may change over the growing season. Heat, wind, and lack of humidity can cause your soil to dry out as quickly. Depending on your conditions, you may have to water as often as twice a day or you may need to water once a week.
The best thing to do is to check the soil frequently, particularly at the beginning of the season, until you get to know your plants’ needs. However, as the summer heats up and the plant grows, be aware that its water needs may change.
Feeding – Calibrachoa are heavy feeders and need to be either given a slow release fertilizer and/or fed a diluted liquid fertilizer regularly. Mix an organic, slow-release fertilizer into my potting medium and then give them a diluted liquid every couple of weeks. Be careful not to over-fertilize by following the directions on whatever brand or type of plant food that you choose. More on Fertilizer
Re-potting – Most calibrachoa are incredibly root-bound when you buy them so there is very little soil left in the pot. This means that your margin of error for watering is very slim and there isn’t much nutrition for the plants to use. When you re-pot calibrachoa, add a slow release fertilizer into the potting mix.
Deadheading – Calibrachoa are considered a “self-cleaning” plant and don’t need to be deadheaded to keep blooming, however, to keep them looking good throughout the growing season give them a serious cutting back towards the end of the summer.
Some favorite varieties of calibrachoa are: