Psephellus Species, Knapweed, Persian Cornflower

Psephellusdealbatus

Family
Asteraceae (ass-ter-AY-see-ee)
Species
dealbatus (day-al-BAH-tus)
Synonym
Centaurea dealbata
Sun Exposure
Full Sun
Sun to Partial Shade
Light Shade
Foliage
Herbaceous
Succulent
Height
18-24 in. (45-60 cm)
24-36 in. (60-90 cm)
Spacing
15-18 in. (38-45 cm)
18-24 in. (45-60 cm)
Hardiness
USDA Zone 3a: to -39.9 °C (-40 °F)
USDA Zone 3b: to -37.2 °C (-35 °F)
USDA Zone 4a: to -34.4 °C (-30 °F)
USDA Zone 4b: to -31.6 °C (-25 °F)
USDA Zone 5a: to -28.8 °C (-20 °F)
USDA Zone 5b: to -26.1 °C (-15 °F)
USDA Zone 6a: to -23.3 °C (-10 °F)
USDA Zone 6b: to -20.5 °C (-5 °F)
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)
Danger
N/A
Bloom Color
Pink
Bloom Time
Late Spring/Early Summer
Mid Summer
Other Details
Category
Perennials
Water Requirements
Drought-tolerant; suitable for xeriscaping
Average Water Needs; Water regularly; do not overwater
Foliage Color
Blue-Green
Where to Grow
Grow outdoors year-round in hardiness zone
Bloom Characteristics
This plant is attractive to bees, butterflies and/or birds
Bloom Size
Other details
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
By dividing the rootball
From seed; direct sow after last frost
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:

Booneville, Arkansas

Edwardsville, Illinois

Saint Charles, Illinois

Wauconda, Illinois

Foxboro, Massachusetts

Constantine, Michigan

Mason, Michigan

Pinconning, Michigan

Hopkins, Minnesota

Minneapolis, Minnesota(2 reports)

Rosemount, Minnesota

Saint Paul, Minnesota

Saint Joseph, Missouri

Manchester, New Hampshire

Buffalo, New York

Wallkill, New York

Richfield, Ohio

Bartlesville, Oklahoma

, Ontario

Knoxville, Tennessee

Austin, Texas

Weatherford, Texas

Salt Lake City, Utah

Leesburg, Virginia

Cathan, Washington

John Sam Lake, Washington

Kalama, Washington

Lynnwood, Washington

North Marysville, Washington

Poulsbo, Washington

Priest Point, Washington

Seattle, Washington

Shaker Church, Washington

Stimson Crossing, Washington

Weallup Lake, Washington

Eau Claire, Wisconsin

Menasha, Wisconsin

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Gardener's Notes:

5
positives
1
neutral
0
negative
Sort By:
Sort By:
C
ROSLINDALE, MA | May 2016 | neutral

According to the RHS, C. hypoleuca is a different species, not a synonym.

M
Coon Rapids, MN (Zone 4a) | April 2008 | positive

Tough species - I have never seen them selfseed. Bloom a bit later than C. montana and have heavily lobed leaves that stays close to the ...Read More

B
Lynnwood, WA | June 2007 | positive

Flowers are wonderful addition to the garden. The plant is spreading though so plant it where you have lots of space. Also it is easy to ...Read More

B
Appleton, WI (Zone 5a) | July 2006 | positive

Nice carefree flower. Finer cut foliage than regular cornflower. Gold finches eat all the seeds so I don't know if it self seeds.

F
Manchester, NH | August 2005 | positive

Mine just flowered this summer for the first time and I love it! No mildew, no bugs eat it, just beautiful flowers, no fuss.

P
Anchorage, AK | July 2004 | positive

Our USDA zone is usually 3, although we have had
several favorable winters lately. The Persian Cornflower
has performed ver...Read More

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