Calibrachoa, also called million bells, is a cousin of the petunia. It has a more limited color range than petunias, finer foliage, a trailing habit and numerous tiny flowers when in bloom. It is most easily and commonly propagated through vegetative cuttings from existing plants. Knowledge of how to take these cuttings and create the right environment for them will give you new plants.
Take a cutting from an existing calibrachoa plant. Look for a healthy shoot with at least three nodes where the leaves connected or once connected to the stem. Clip the stem with scissors, making sure to include the nodes.
Fill a small pot for each cutting with a potting medium of half peat and half perlite. This will provide enough aeration and just the right amount of moisture for the calibrachoa cuttings.
Prepare the cutting by stripping the bottom 1/3 of all its leaves. Also remove any flowers that still remain. Dip the bottom end in a rooting hormone. Calibrachoa does not need this to root, but the hormone will encourage it to root more quickly.
Stick one cutting in each pot, water the potting medium deeply and place clear plastic bags over each to increase humidity. The cuttings root best at about 70 degrees Fahrenheit. Placing a heating pad underneath the cutting may encourage faster growth.
Set the potted cuttings down in a south- or east-facing window with filtered sunlight for best results. Make sure the potting medium does not dry out. Take the plastic bags off the top of the cuttings when they start to leaf out on their own.