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Centaurea Species, Cornflower, Perennial Bachelor Button, Red Knapweed

Centaureaatropurpurea

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Centaurea atropurpurea by JonnaSudenius
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Family
Asteraceae (ass-ter-AY-see-ee)
Info
Genus
Centaurea (sen-TAR-ee-uh)
Info
Species
atropurpurea (at-ro-pur-PURR-ee-uh)
Info
Synonym
Centaurea oliveriana
Sun Exposure
Full Sun
Foliage
Herbaceous
Height
12-18 in. (30-45 cm)
18-24 in. (45-60 cm)
24-36 in. (60-90 cm)
Spacing
18-24 in. (45-60 cm)
24-36 in. (60-90 cm)
Hardiness
USDA Zone 7a: to -17.7 °C (0 °F)
USDA Zone 7b: to -14.9 °C (5 °F)
USDA Zone 8a: to -12.2 °C (10 °F)
USDA Zone 8b: to -9.4 °C (15 °F)
USDA Zone 9a: to -6.6 °C (20 °F)
USDA Zone 9b: to -3.8 °C (25 °F)
USDA Zone 10a: to -1.1 °C (30 °F)
Danger

Unknown - Tell us

Bloom Color
Dark Purple/Black
Maroon/Burgundy
Bloom Time
Mid Summer
Late Summer/Early Fall
Other Details
Category
Perennials
Water Requirements
Drought-tolerant; suitable for xeriscaping
Average Water Needs; Water regularly; do not overwater
Foliage Color
Bronze
Where to Grow
Grow outdoors year-round in hardiness zone
Bloom Characteristics
Flowers are good for cutting
Flowers are good for drying and preserving
This plant is attractive to bees, butterflies and/or birds
Bloom Size

Unknown - Tell us

Other details
May be a noxious weed or invasive
Soil pH requirements
6.1 to 6.5 (mildly acidic)
6.6 to 7.5 (neutral)
7.6 to 7.8 (mildly alkaline)
Patent Information
Non-patented
Propagation Methods
Self-sows freely; deadhead if you do not want volunteer seedlings next season
Seed Collecting
Allow seedheads to dry on plants; remove and collect seeds
Regional

This plant is said to grow outdoors in the following regions:

Cicero, Indiana

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4 members have or want this plant for trade

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Gardener's Notes:

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coriaceous
ROSLINDALE, MA | January 2016 | neutral

Deep/wine red flowers in early summer may rebloom if deadheaded. Silvery, deeply divided foliage is good throughout the season.
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