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Canterbury Bells

How to Care for a Campanula Plant

Campanula also is known as bellflower. There are approximately 300 varieties of campanula, including annuals, biennials and perennials. Their trumpet-shaped flowers are white, rose, blue or purple. The different varieties grow from 3 inches high to about 4 feet high. The shorter varieties make good ground cover for areas that do not receive foot traffic.

  • Campanula also is known as bellflower.
  • The different varieties grow from 3 inches high to about 4 feet high.

Grow campanula in full sun to partial shade. The shorter the variety, the less sun required. Campanula likes the dappled shade of deciduous trees and makes an excellent ground cover beneath them. It also benefits from the shade tree's roots, which loosen the soil as they grow deep underground in search of moisture. The roots of campanula will do the same thing.

Grow campanula in unimproved soil. It grows well in any type of soil, except heavy clay or waterlogged, marshy soil.

Water campanula only in times of extreme drought. Its deep-growing roots will seek out and find water deep underground and will thrive with only natural rainfall.

Cultivate to remove weeds as campanula does not favorably compete with them, especially lawn grasses. Put down a mulch of hay or straw about 2 inches thick to suppress the growth of weeds and reduce competition for water and nutrients.


Supplemental fertilizing of campanula flowers is not necessary. It grows and thrives with very few nutrients.

Canterbury Bells

Canterbury Bells

(Campanula medium)

What an elegant flower! This dramatic, tall plant is an excellent backdrop for your shorter annuals and perennials. Flower colors include purple, violet, blue, lavender, pink and white. The bell-shaped flowers will remind you of an English cottage garden. Spring to early summer bloomer. Also works well as a cut flower. Easy to grow from seed.

Flower Type: Biennial
Bloom Time: Spring
Height:2' to 3' tall
Exposure: Light shade or sun

When to Sow Outside: Late spring or early summer for blooms the second year. This plant is a biennial which produces foliage the first year and flowers the second year.
When to Sow Inside: Six to eight weeks before the last frost. It may bloom the first year if started indoors.
Seed Spacing: 1"
Seed Depth: Press onto surface of the soil.
Days to Emerge: 15 - 20
Thinning: 6" - 2' apart

Bells of Ireland Fast Facts


Despite its name, the plant is not from Ireland but is a member of the mint family from Western Asia, including Turkey and Syria.


Bells of Ireland grow to 2 or 3 feet. They prefer sandy, well-drained soil and lots of sun. If planted in too much shade, the spikes will lean.


Sow Bells of Ireland seeds indoors for an early start, or plant them right in the garden. The seeds require light to germinate, so barely cover them with soil.

Interesting Tidbit

Bells of Ireland are also sometimes called "shell flowers" because the plant's large white seeds appear at the bottom of the calyx.


Bells of Ireland make an excellent dried flower. Cut them when all the blooms are open and hang upside down to dry. They also do wonderfully in arrangements.


The stems have tiny thorns, so gloves are recommended when handling Bells of Ireland.

Canterbury Bells or Bellflowers

(Campanula medium)

Canterbury bells are classic cottage-garden flowers. The annual forms grow in noteworthy 2 1/2-foot-tall pyramids, which are covered in late summer with spikes of large bell-shaped pink, rose, lavender, blue or white blossoms, each 2 inches or more long. A "cup-and-saucer" variety, C. medium calycanthema, bears flowers with double bells, one inside the other. Although this variety is a biennial, it will blossom the first year if started indoors. The handsome plants look good in an annual border and make unusual, long-lasting cut flowers. They look best in massed plantings in borders or among shrubs.

Canterbury bells require sun and rich, moist soil. Sow seeds in the garden as soon as the soil can be spaded and raked in the spring, or start them indoors six to eight weeks before the last frost for earlier flowering. Transplant seedlings started indoors into 3-inch pots when they are large enough to handle, then move them into a cold frame two weeks before the last frost is due to enable them to become acclimated to outdoor conditions gradually. Set them in the garden, 12 inches apart, when all frost danger has passed. Protect from strong winds. Light support may be necessary when plants are in full bloom. They will benefit from monthly side-dressings. Annual Canterbury bells require about six months to grow from seeds to flowers.

  • Type
    annual (or biennial)
  • Propagation
  • Light
    full sun
  • Flower Color
    pink, rose, lavender, white, blue
  • Bloom Time
  • Height
    30 inches
  • Width
    12-15 inches
  • Soil Requirements
    rich in organic matter, well drained
  • Zones
    not suited to tropical or dry regions
  • Uses
    bed, border, cutflowers, massed planting
  • Canterbury bells are classic cottage-garden flowers.
  • The handsome plants look good in an annual border and make unusual, long-lasting cut flowers.

Canterbury Bells Fast Facts


Canterbury bells grow as pyramid-shaped bushes that can reach 2 1/2 feet tall and from 12 to 15 inches wide. The bell-shaped flowers are about 2 inches long and come in pink, rose, lavender, blue or white.


Canterbury bells need full or partial sun and rich, moist soil. The seeds can be started indoors six to eight weeks before the last frost, or they can be directly sown in the garden when danger of frost has passed. Plant the seedlings outdoors 12 inches apart in an area protected from winds.


Give Canterbury bells fertilizer about once a month. When they get high, attach them to a stake to prevent them from falling over.


Because they are so tall, Canterbury bells can be used at the back of a garden or against a wall.


Canterbury bells can have problems with insects like slugs, snails, vine weevils, spider mites and aphids. Diseases include powdery mildew, rust, Septoria and Ramularia leaf spot, and southern blight.

Gardening Information on Marine Bell Flowers


The trailing form of Marine Bells is perfect for hanging baskets and other containers, as well as flower borders. The flowers attract hummingbirds and butterflies. Marine Bells can be cut back, potted and moved inside for a houseplant before the first frost in fall.

Growing Conditions

Marine Bells grow best in rich, well-drained soil that remains evenly moist. They grow in partial shade to full shade, and need long days to bloom. They are hardy to 45 degrees.

Growing From Seed

Marine Bells can be sowed indoors eight to 10 weeks before the predicted date of the last frost. The seeds need light to germinate and should not be covered. They should be kept in a moderately warm place--between 70 and 75 degrees. The seeds will germinate in seven to 21 days.

  • Marine Bells can be sowed indoors eight to 10 weeks before the predicted date of the last frost.
  • The seeds need light to germinate and should not be covered.

Growing Tips

Marine Bells should be pinched back regularly to encourage new growth for a bushy plant. The flowers are more deeply colored when the plants receive afternoon shade.


Marine Bells will wilt during periods of high temperatures and drought. Too much water or fertilizer will produce more foliage and fewer flowers.

How to Protect Canterbury Bells

Stake taller varieties of Canterbury bells to protect them from blowing over in strong winds. Use a plant support purchased from a garden center or use twine to secure the plant to a bamboo cane or dowel rod.

Sprinkle a ring of diatomaceous earth, crushed eggshells or wood ash around the flowers to protect Canterbury bells from slugs and snails.

Prevent rust fungus from developing on Canterbury bells. Plant them in a garden site with good air circulation. Direct water toward the roots of the plant and avoid getting the leaves wet. Remove any affected plants or plant parts to prevent them from spreading to other plants. Do not add these to the compost. The Connecticut Agricultural Experiment Station states, “Although not usually necessary, applications of fungicides can be made when new growth emerges in the spring.”

How to Plant Million Bells (Calibrachoa)

Choose a spot in full sun and in soil that drains water well to plant million bells. Mix in 2 to 3 inches of peat moss or compost to the top 8 to 12 inches of soil to improve drainage. For clay soil, also mix in equal amounts of coarse sand.

Plant million bells as deep as they were planted in their original containers. Space them approximately 20 to 30 inches apart, depending on the million bell variety.

Water the newly planted million bells with 1 inch of water. Water at the base of the plants rather than from overhead, which can wilt the flowers and cause fungus to grow on the foliage.


Plant million bells in containers, if desired. Trailing varieties are also popular plants for hanging baskets. Use a potting soil mix that contains material that retains moisture well, such as coir or rock wool.

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