Centaurea montana
Mountain knapweed, Perennial cornflower, Mountain bluet, Perennial bachelor's buttons
- Height × spread
- 0.45m × 0.5m
- Position
- Full sun
- Hardiness
- Colder than -20C (RHS H7)
- Flowers
- Summer
Availability
Generally available in Spring & Summer
Many plants are seasonal. Call 01234 567890 to check current stock.
About this plant
This is one of those charming cottage garden plants. It is striking with its jagged blue petalled flower heads that flare out at their ends and big red-brown eyes. The lance-shaped toothy leaves have a floppy habit and produce a large sprawling clump.
- Flower colour
- Blue
- Foliage colour
- Green
- Variegated
- No
- Scent
- No
- Shape
- Fan
- Height
- 0.45m
- Spread
- 0.5m
- Season of interest
- Summer
- Flowers in
- Summer
- Evergreen
- Deciduous
- Garden style
- Seaside garden, Cottage garden
- Sun or shade
- Likes full sun, tolerates part shade
- Soil type
- Gravelly soil, Loam (normal), Poor soil, Sandy soil
- Soil pH
- All types
- Drainage
- Moisture retentive soil, Well drained soil, Dry soil, Drought resistant
- Hardiness
- Colder than -20C (RHS H7)
- Borders & containers
- Borders
- Use for
- Bee attraction, Butterfly attraction
- Hazards
- No
Spring
Spring-Autumn · Outdoors
Water in dry periods
Established plants in the ground can cope with 7-10 days of dryness, and shrubs often manage 2 to 3 weeks. Water one section of the garden thoroughly each day rather than a little everywhere. Check plants in pots more often, especially in hot weather.
Summer
Summer - early · Outdoors
Feed a general fertiliser
Where plants have moderate needs for nutrients, they can simply be given a general feed, fairly early in the growth season so that the growth has plenty of time to harden off before the cold weather.
Give plants a general boost with the application of a general purpose fertiliser which is spread around the root area of the plant, with amounts as directed on the feed label.
Planting & general
Planting
Deadhead blooms during flowering season
Remove flowers as they turn brown and fade. Snip the stem just below the bloom. This will keep the plant tidy and encourage more flowers.
The removal of spent flowers encourages the plant to produce fresh ones, rather than spend its energy on the development of seeds.
Found in
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Centaurea 'Jordy'
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Centaurea 'Silver Feather'
Silver Feather knapweed
Centaurea bella
Beautiful knapweed
Centaurea cineraria subsp. cineraria
Dusty miller