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Centaurea cyanus 'Blue Diadem' (Cornflower 'Blue Diadem')

Beginner
skill rating
1 hour care
per year
0.75m
Max height
0.3m
Max spread
1 years
To maturity

Plant details

Botanical name

Centaurea cyanus 'Blue Diadem'

Other names

Cornflower 'Blue Diadem', Blue-bottle 'Blue Diadem', Bachelor's buttons 'Blue Diadem'

Genus

Centaurea Centaurea

Variety or Cultivar

'Blue Diadem' _ 'Blue Diadem' is an upright, branching annual with lance-shaped, sometimes pinnate, grey-green leaves and deep blue flower heads in late spring and throughout summer.


Centaurea cyanus 'Blue Diadem' is: Deciduous

Habit

Branching, Upright

Flower

Dark-blue in Spring; Dark-blue in Summer

Foliage

Grey-green in Spring; Grey-green in Summer; Grey-green in Autumn

How to care

Watch out for

Pests

Generally pest free

Powdery mildew Powdery mildew

General care

Pruning

Deadhead regularly to extend the flowering season.

Propagation

Self-seeds readily

Propagation methods

Seed


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Where to grow

Centaurea cyanus 'Blue Diadem' (Cornflower 'Blue Diadem') will reach a height of 0.75m and a spread of 0.3m after 1 years.

Suggested uses

Beds and borders, Bees (attract & feed bees), Coastal, Containers, Flower Arranging, Wildflower, Wildlife

Cultivation

Grow in well-drained soil in full sun. Autumn sowing will produce earlier-flowering plants.

Soil type

Loamy, Sandy

Soil drainage

Well-drained

Soil pH

Acid, Alkaline, Neutral

Light

Full Sun

Aspect

South, West

Exposure

Exposed, Sheltered

UK hardiness Note: We are working to update our ratings. Thanks for your patience.

Hardy (H4)

Companion plants

We do not currently have companion plants added for this plant.

Botanical name

Centaurea cyanus 'Blue Diadem'

Other names

Cornflower 'Blue Diadem', Blue-bottle 'Blue Diadem', Bachelor's buttons 'Blue Diadem'

Genus

Centaurea Centaurea

Variety or Cultivar

'Blue Diadem' _ 'Blue Diadem' is an upright, branching annual with lance-shaped, sometimes pinnate, grey-green leaves and deep blue flower heads in late spring and throughout summer.

Foliage

Deciduous

Habit

Branching, Upright


Colour

Flower

Dark-blue in Spring; Dark-blue in Summer

Foliage

Grey-green in Spring; Grey-green in Summer; Grey-green in Autumn


How to care

Watch out for

Pests

Generally pest free

Specific diseases

Powdery mildew

General care

Pruning

Deadhead regularly to extend the flowering season.

Propagation

Self-seeds readily

Propagation methods

Seed


Monthly care advice


Where to grow

Centaurea cyanus 'Blue Diadem' (Cornflower 'Blue Diadem') will reach a height of 0.75m and a spread of 0.3m after 1 years.

Suggested uses

Beds and borders, Bees (attract & feed bees), Coastal, Containers, Flower Arranging, Wildflower, Wildlife

Cultivation

Grow in well-drained soil in full sun. Autumn sowing will produce earlier-flowering plants.

Soil type

Loamy, Sandy

Soil drainage

Well-drained

Soil pH

Acid, Alkaline, Neutral

Light

Full Sun

Aspect

South, West

Exposure

Exposed, Sheltered

UK hardiness Note: We are working to update our ratings. Thanks for your patience.

Hardy (H4)

USDA zones

Zone 10, Zone 9, Zone 8, Zone 7, Zone 6, Zone 5, Zone 4, Zone 3, Zone 2

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This plant likes... Garden match
Soil types: Loamy, Sandy Tell us...
Soil drainage: Well-drained Tell us...
Soil pH: Acid, Alkaline, Neutral Tell us...
Light: Full Sun Tell us...
Aspect: South, West Tell us...
Exposure: Exposed, Sheltered Tell us...
Hardiness: Hardy (H4) Tell us...

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