Milky bellflower
Campanula lactiflora · Campanulaceae
Great domed heads of hundreds of small, open bells in milky lavender-blue, on leafy stems as tall as a person's shoulder.
- Size
- 4½ ft tall, 24 in wide
- Zones
- 5 to 7
- Light
- Full sun to part sun
- Flowers
- Late June to early August
- Pets
- Not checked
- Job in a bed
- Drift
A bed built around milky bellflower
The planner designed this bed around milky bellflower when this page was made: a 12 × 6 ft (3.7 × 1.8 m) cottage garden in zone 6, full sun. It chose the other plants from the 966 that suit those conditions, and says below why milky bellflower stands where it does.
The plants
- 1 Milky bellflower × 3, lavender
- 2 Creeping phlox 'Emerald Blue' × 6, blue
- 3 Mouse-ear coreopsis 'Nana' × 19, yellow
- 4 Little bluestem 'The Blues' × 3, tan
- 5 Inkberry 'Gem Box' × 1, dark green leaves
- 6 Narrow-leaved foxtail lily × 3, yellow
- 7 Netted iris × 12, purple
Why this plant
- The only bells. The others are open bowls, daisies and spires. Shape reads at a distance, where colours blur.
- The only lavender.
Why here
- Anchors a back corner. At 4½ ft it is the tallest plant here, and the tallest close the ends of the bed, where they stand in front of nothing.
- A step in the back row. Next to inkberry 'Gem Box' (2½ ft): no two neighbours there are the same height, so the back steps up and down like a skyline.
- 3 plants in one group. Massed, one kind reads as a single shape. Scattered, it would look spotty.
Why now
- In flower for 7 weeks. From late June to early August.
- Fills a gap. For three of those weeks nothing else on the plan is in flower.
Planned as a cottage garden: 32 of the 32 plants (100%), bulbs aside, stand alone or in groups of no more than five, small enough for the kinds to mingle. Cool colours (lavender, blue and purple) with yellow as the warm note, and tan to calm things between them. The bed is tied together by its repeats: two kinds come round again along it, mouse-ear coreopsis 'Nana' and creeping phlox 'Emerald Blue'.
The planner's own design check: 11 Excellent, 5 Good, 1 Satisfactory. It flags one thing to watch: Nothing on this plan is highly poisonous or an aggressive spreader.
Open this bed in the planner Change its size, the sun or the style, move plants about, or swap one for another.
Where milky bellflower goes in a border
At 4½ ft it belongs at the back of a bed. In the planner's ten height classes it is tall (4 to 5 ft).
Its job: drift. Planted in a small group of three or five, and repeated further along in the other number.
The grandest bellflower, and a mainstay of the English summer border. Stake it early or cut it back by a third in May, which gives a shorter, later plant that stands alone.
- Height in a summer border
- Cottage gardens
- Partnering with roses
What to plant with milky bellflower
Plants recorded as good partners for it, and what each pairing does:
- English rose: blue against orange, opposite each other on the colour wheel, if you choose those colours, in flower together for seven weeks.
- Peony: flowers first, late May to late June, so the spot is never empty.
- Lady's mantle: in flower together for two weeks, from late June; low enough (18 in) to stand in front of it; happy in the same moist soil.
Questions about milky bellflower
Does milky bellflower need sun or shade?
Milky bellflower grows in full sun (6 or more hours of direct sun a day) and part sun (4 to 6 hours of sun, including some afternoon sun).
It wants soil that stays evenly moist, rich in organic matter, and a good soak in dry spells.
What zones does milky bellflower grow in?
USDA zones 5 to 7. It is hardy to zone 5, which means it survives winter nights down to about −10 °F (−23 °C).
Above zone 7 it struggles: the zones measure winter cold, but a plant's top zone usually means the summers are too hot or the winters too mild for it to rest.
Gardening in Canada? Use the USDA zone for your town: Canada's own zone map uses different numbers.
When does milky bellflower flower in my zone?
In zone 5 it flowers late June to early August. As a summer flower it moves about half a week for every zone: earlier where it is warmer.
| Zone 5 | Late June to early August |
|---|---|
| Zone 6 | Late June to early August |
| Zone 7 | Late June to early August |
Worked out from Hopkins' bioclimatic law: spring arrives about four days later for each degree of latitude north, and one zone is roughly two degrees. A warm spring or a cold one moves any garden two weeks either way.
How far apart should milky bellflower be planted?
20 in (50 cm) apart, from the middle of one plant to the middle of the next. That is a little closer than its full width of 24 in (60 cm), so a group knits into one patch.
It grows 4½ ft (130 cm) tall. Give it the full distance from anything taller, or it will lean out towards the light.
How many milky bellflower plants do I need?
At 20 in apart, set out in staggered rows:
- 4 to fill 10 square feet (about 1 m²)
- 7 for a single row 10 ft (3 m) long
- 14 to fill a 4 × 8 ft bed on its own
In a mixed border, plant it as a group of three or five, with a second group further along in the other number.
In the bed above, the planner used three in one group.
Is there a native plant like milky bellflower?
Milky bellflower is not native to North America. These North American natives come closest to doing its job:
- Swamp milkweed: the same job in a bed and the same flowering time; 4 in wider, pink or white, not lavender.
- Bee balm 'Jacob Cline': the same job in a bed and the same flowering time; 4 in wider, red, not lavender.
- Garden phlox 'David': the same job in a bed; 8 in shorter, flowers mid July to early September.
Matched the way the planner's Swap button matches plants: the same job in a bed, then size, then flowering time.
Will milky bellflower spread?
It seeds itself about; the risk of it taking over is moderate. Self-seeds in moist soil, and the seedlings vary in colour. Cut off the spent heads.
What flowers after milky bellflower?
Milky bellflower is over by early August. These start as it finishes and carry the same spot on, so it never goes flat:
- Japanese anemone: from mid August to early October, 3 ft tall, to stand in front of it and cover its fading stems.
- Little bluestem 'Standing Ovation': from early August to mid September, 3½ ft tall, to stand in front of it and cover its fading stems.
- Lilyturf: from early August to mid September, 16 in tall, to stand in front of it and cover its fading stems.
What does milky bellflower look like in winter?
Milky bellflower dies down to the ground and there is nothing to see until spring. The old stems can be cut in autumn, or left until spring as shelter for overwintering insects.
More Campanula
- Bellflower 'Dickson's Gold' Campanula garganica 'Dickson's Gold'
- Bellflower 'Kent Belle' Campanula 'Kent Belle'
- Bellflower 'Sarastro' Campanula 'Sarastro'
- Carpathian bellflower Campanula carpatica
- Carpathian bellflower 'Blue Clips' Campanula carpatica 'Blue Clips'
- Clustered bellflower Campanula glomerata
- Dalmatian bellflower Campanula portenschlagiana
- Fairy thimbles Campanula cochleariifolia
- Harebell Campanula rotundifolia
- Peach-leaved bellflower Campanula persicifolia
- Serbian bellflower Campanula poscharskyana
- Spotted bellflower 'Cherry Bells' Campanula punctata 'Cherry Bells'
In these guides
- Tall perennials and grasses for the back of a border
- Plants with blue flowers
- Plants for a white garden
Every fact on record
- Type
- Perennial
- Size
- 4½ ft (130 cm) tall, 24 in (60 cm) wide
- Plant
- 20 in (50 cm) apart
- Height class
- Tall (4 to 5 ft)
- Place in the bed
- Back
- Flowers
- Late June to early August; hanging bells; lavender, blue, white, pink
- Leaves
- Medium texture, herbaceous; green
- Shape
- Upright, self-seeding
- Hardy in
- USDA zones 5 to 7
- Light
- Full sun, part sun
- Soil
- Rich, evenly moist
- Water
- Moderate
- Feeding
- Light, in spring
- Family
- Campanulaceae
Checked against VASCAN (plants of Canada). Flowering times are for zone 5: later in colder zones, earlier in warmer ones. Toxicity and spread information is a general gardening guide, not veterinary or medical advice, and invasive status varies by region. If a person or pet eats a plant, contact poison control or a vet. Check your local invasive species list before planting anything with a spread warning.