The bright flowers of the calibrachoa (Calibrachoa x hybrida), also known as million bells, brighten gardens and hanging baskets. While grown as an annual in most climates, calibrachoa is actually a tender perennial and may overwinter outdoors in sheltered, frost-free gardens of U.S. Department of Agriculture plant hardiness zones 9 through 11. While calibrachoa is normally propagated with cuttings, collecting the seeds is possible for an enthusiast of these South American natives.
Collecting the Seeds
Not every flower produces seed, but there are a lot of flowers on each of these 8- to 12-inch tall and 10- to 24-inch-wide trailing plants.
Monitor the plants, watching for swelling under the flowers as they fade and die back. Flowers pollinated by bees, butterflies or hummingbirds may develop seed pods.
Snip the drying seed pods off at the stem as they turn brown but before they burst open. Drop the seed pods into a paper bag.
Spread the seed pods in a single layer in a shallow cardboard box. Place the box in a warm, dry location where the pods can continue to dry for one to four weeks.
Break open the seed pods over newspapers and shake out the tiny seeds. Crush the pods if necessary. Pick out the pods and debris, leaving small amounts of chaff and the seeds.
Pour the seeds into envelopes or small jars. Use a permanent marker to clearly label the containers with the flower name and date. Store in a cool, dry location until early spring.