Ornamental · Campanulaceae
Bellflower
Campanula persicifolia
Give it cool weather, sun, and well-drained soil, and the bellflower rings out blue bells every summer.
Full sun
Every 5–7 days
USDA 3–7
2–3 ft · 0.5–0.9 m
Overview
Bellflowers bring an easy wash of blue and white to the early-summer border. The peachleaf bellflower sends up slim stems hung with large, outward-facing bells, blooming from June into July. It belongs to a big family of Campanula that ranges from tall border plants to low edging mounds.
This is a cool-climate perennial, hardy from zone 3 to 7 and happiest where summers stay mild. It comes back year after year and slowly forms a clump you can divide for more plants. Heat is its weakness, so gardeners in warm regions give it afternoon shade and a steady drink.
Most bellflowers ask for very little. Give them sun, drainage, and room to breathe, and they reward you with weeks of bloom. Deadhead the spent flowers and they often ring out a second flush later in the season.
Care
The short version: full sun, or afternoon shade where summers run hot, in average well-drained soil kept evenly moist. Deadhead the spent blooms, divide the clump every few years, and skip the heavy feeding.
Light
Bellflowers do best in full sun but take partial shade without complaint. Where summers turn hot, give them afternoon shade, which keeps the plants cooler and the blooms lasting longer.
Water
Keep the soil at average, even moisture and water every 5 to 7 days in dry spells. The plants want drainage above all, so steer clear of ground that stays soggy or bakes bone dry. Add extra water in hot regions from zone 7 up.
Soil
Almost any well-drained soil suits them, from loam to sand to ground rich in organic matter. They handle a wide pH range, anywhere from 6.0 to 8.0, so most garden beds will do.
Temperature
This is a cold-hardy plant, riding out winters down to -29°F (-34°C). It struggles once summer heat climbs past 86°F (30°C), which is why it fades in warm-climate gardens without some shade.
Humidity
Ordinary outdoor humidity is fine, so there's no level to manage. Air movement matters more, since muggy, still air with warm nights is what wears these cool-weather plants down.
Feeding
Bellflowers need little. A light, balanced feed about four weeks before bloom is plenty, and like most perennials they get along on lean soil rather than rich.
Pruning
Deadhead spent blooms to push a second flush and rein in self-seeding. When the stem leaves start to fade, cut the flowering stalks back to the basal rosette, and pinch the plant now and then to keep it bushy.
Repotting
Bellflowers grow into clumps that tire over time. Divide them every 3 to 4 years to keep the flowering strong, and watch for crowded growth or fewer blooms as your cue to lift and split.
Size & spacing
Plants stand 1.5 to 3 feet (46 to 91 cm) tall and spread 12 to 18 inches (30 to 46 cm) wide. Give each one that much room so air moves freely and the clump can fill in.
When to plant
Bellflowers run on a cool-season rhythm. Start seed indoors in late winter, set young plants out in spring once the frost has passed, and the bells open from June into July.
Northern hemisphere
Southern hemisphere
Typical months for a temperate climate: start earlier in warm zones, later where spring frosts linger.
- Sow: Late winter to early spring (8-10 weeks before last frost)
- Plant: Spring after last frost
- Harvest: June to July
Hardiness
USDA hardiness zones: 3–7
Temperature: down to -40°C
Troubleshooting
Bellflower problems are few and usually easy to read. Most come down to chewing pests on the leaves or summer heat wearing the plant down. Match what you see below and step in early.
Plants fading fast or dying out where summers run hot
Bellflowers are cool-weather plants, and heat and humidity wear them down where nights stay near 70°F (21°C). They falter south of zone 7, so give them afternoon shade and steady moisture if your summers are punishing. The surest fix is to plant them in the coolest corner you have.
Fix:
- Site plants where they receive afternoon shade in hot regions
- Ensure good drainage and adequate moisture
- Choose cooler microclimates for planting
Ragged holes in leaves and flowers, with silvery trails nearby
Those chewed edges and the shine left behind point to slugs and snails, which feed after dark and hide by day. Go out with a flashlight in the evening and pick them off by hand. Clear away the mulch and old leaves they shelter under, and set iron-phosphate bait if they keep coming back.
Fix:
- Hand-pick slugs and snails in the evening
- Remove plant debris and mulch that provides hiding spots
- Use traps or iron-phosphate baits if pressure is high
Curled new growth covered in tiny insects and sticky film
Clusters of soft green or black specks on the tender tips, along with a sticky coating, mean aphids are at work. Blast them off with a sharp jet of water, and follow with insecticidal soap if the colony holds on. Lay off the nitrogen feed, since the soft new growth it pushes is exactly what draws them in.
Fix:
- Spray plants with a strong jet of water to dislodge aphids
- Apply insecticidal soap if infestation is heavy
- Encourage natural predators such as lady beetles
Toxicity
Good news for households with animals: bellflower is not known to be toxic to pets, livestock, or people. It stays off the standard poison lists, and some Campanula are even eaten by foragers. A pet that chews a lot of foliage might get a brief stomach upset, nothing more.
Safe for
People · Cats · Dogs · Horses · Rabbits · Livestock · Birds
Cats None
Bellflower is safe for cats, with no toxin on record. A cat that nibbles a leaf might get a brief stomach upset, the same as with any plant it shouldn't be eating.
Dogs None
Dogs can be around bellflower without worry, since it stays off the standard toxic-plant lists. At worst a dog that wolfs down a mouthful of foliage may drool a little or have a loose stool for a day.
Horses Safe
Nothing in bellflower is known to harm horses. A grazing horse can crop it without any reported ill effect.
Rabbits Safe
Rabbits are fine around bellflower, and the foliage carries no toxin that would trouble them.
Livestock Safe
Cattle, goats, and sheep can graze near bellflower safely, since it holds no compound known to poison stock.
Birds Safe
Bellflower poses no danger to birds. Backyard poultry and wild birds can move through a planting without harm.
People Safe
Bellflower is safe around people, and some Campanula are eaten by foragers. Children are in no danger from a stray leaf or flower in the garden.
Generally considered safe around pets and people; as with any plant, ingesting large amounts of foliage may cause mild, temporary stomach upset.
Varieties
The genus Campanula is large, but a few bellflowers turn up again and again in gardens. These are the ones worth knowing by name.
Campanula persicifolia (Peachleaf bellflower)
Tall, upright stems reach 1.5 to 3 feet and carry large outward-facing bells in white through violet-blue from June into July.
Campanula carpatica (Carpathian bellflower)
A low, compact mound of upward-facing blue, purple, or white bells that makes a tidy edging plant.
Campanula glomerata (Clustered bellflower)
Stands 6 to 24 inches tall and gathers its violet to lavender-blue flowers into dense clusters at the stem tips.
Campanula medium (Canterbury bells)
A biennial bellflower grown for its big cup-and-saucer blooms.
How to propagate
Bellflowers are simple to multiply, whether you split a clump, sow seed, or root a basal cutting.
DivisionEasy
Spring or early fall · One growing season
Division is the easiest way to make more bellflowers and keep old clumps vigorous. Lift and split an established plant in spring or early fall, and each piece settles in within a single growing season.
SeedModerate
Sow indoors late winter to early spring or allow self-seeding outdoors · Often blooms the second year from seed
You can start bellflower from seed indoors in late winter or early spring, or simply let the plants drop their own. Seed-grown plants usually wait until their second year to flower, so deadhead through the season if you want to keep the self-sowing in check.
Stem cuttingsModerate
Spring to early summer from basal growth · Several weeks to root
Cuttings give you exact copies of a plant you like. Take basal shoots in spring or early summer, and they root over several weeks into new plants.
Myths
All bellflowers are dangerously poisonous to cats and dogs.
Campanula carries no reported toxin for pets. It is missing from Cornell's list of plants toxic to dogs, NC State's profile gives no poison warning, and some species are even eaten by foragers. Bellflower is safe to grow around cats and dogs.
Every bellflower is a harmless garden ornamental.
Creeping bellflower, Campanula rapunculoides, is a different story. It spreads hard by both seed and underground rhizomes and is brutal to dig out once established. Skip that species and plant a well-behaved bellflower instead.