Caren White is a Master Gardener and instructor at Home Gardeners School. She has been associated with Rutgers Gardens for over a decade.
Some of my favorite flowers are old fashioned cottage garden flowers. Canterbury bells grew in my mother’s garden when I was a child. Not surprisingly, I have added them to my own garden.
What are Canterbury Bells?
Canterbury bells (Campanula medium), also known as Cups and Saucers, are biennial flowering plants that are native to Southern Europe. The plants spread to the rest of Europe where they have naturalized because they readily self-sow. They were brought to North America by European colonists who brought many flowers and plants from their countries of origin to grow in their new homes. Canterbury bells have also naturalized throughout North America.
Because they are native to the Mediterranean area which is very dry, they do not grow well in the very humid climate of the Southeast. They grow better in the cooler, dryer climate of the Northeast US.
The plants are hardy in zones 5 – 8. They are biennial which means that they only live for two years. The first year, they grow a rosette of leaves which dies after the first frost in the fall. The second year, the rosette of leaves returns and the plants flower, produce seed and then die permanently after the first frost.
The second year, when they grow more upright, the plants can be 18 – 36 inches feet tall and 9 – 16 inches wide.
The flowers, which are bell shaped, grow from the upright stems. They can be pink, white, blue or violet. Bloom time is May through July. If you allow the flowers to die and go to seed, the seed will drop into your garden and new plants will start growing which will bloom the following year.
To ensure blooms every year, most gardeners plant Canterbury bell seeds every year so that they will have both first and second year plants in their gardens every year.
Grow them in your cutting garden. Canterbury bells can be used in cut flower arrangements.
Bee keepers believe that the pollen of Canterbury bells makes especially flavorful honey.
How to Grow Canterbury Bells
Canterbury bells are easily grown from seed but some gardeners may prefer purchasing second year plants from their local nursery so they will have blooms that year. Plant the purchased plants 12 – 15 inches apart. When planted singly, they may need staking. Plant them in a bunch to maximize the impact of their flowers and to provide support for individual plants.
Canterbury bells grow in both full sun and partial shade. They grow best and require less staking when grown in full sun. They like soil that is rich and well-draining. The soil should be kept evenly moist. Adding a thick layer of mulch will keep the soil moist and discourage weeds which compete with your plants for sunlight and water.
Fertilize your plants in the late spring using a balanced fertilizer such as 10-10-10. Water your plants regularly during the growing season.
How to Grow Canterbury Bells From Seed
You can start your seeds indoors or outdoors. If you are starting your seeds outdoors directly in your garden, surface sow them in the late spring or early summer. Do not cover the seed. It needs light to germinate. Keep the soil evenly moist. Germination should occur in 2 – 3 weeks. Thin your seedlings to 12 – 15 inches apart.
The seedlings will form rosettes of leaves which will die after the first frost. The following spring, the plants will start growing again and flower.
You can also start your seeds indoors, 6 – 8 weeks before your last frost. Surface sow them on pre-moistened soil in a container. I always water my soil before I plant seeds because I’ve discovered that if I water afterwards, especially with surface sown seeds, both the soil and the seeds wash away.
Don’t cover the seeds with soil. They need light to germinate. Germination should occur in 2 – 3 weeks. The seeds of biennial plants take longer to germinate than the seeds of annual plants so be patient.
Place your seedlings in a sunny window. You can transplant your seedlings into your garden after your last frost when the outdoor soil temperature reaches 50⁰F. Space them 12 – 15 inches apart.
The first year, you will just have rosettes of leaves which will die after the first frost in the fall. The plants will start growing again in the spring. They will produce flowers during this second year.
© 2020 Caren White