Persian Cornflower, Knapweed
Centaurea dealbata

Family: Asteraceae (ass-ter-AY-see-ee) (Info)
Genus: Centaurea (sen-TAR-ee-uh) (Info)
Species: dealbata (day-al-BAH-tuh) (Info)
Synonym:Centaurea hypoleuca

Category:

Perennials

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)

Sun Exposure:

Full Sun

Sun to Partial Shade

Light Shade

Danger:

N/A

Bloom Color:

Pink

Bloom Time:

Late Spring/Early Summer

Mid Summer

Foliage:

Herbaceous

Blue-Green

Velvet/Fuzzy-Textured

Other details:

This plant is attractive to bees, butterflies and/or birds

Drought-tolerant; suitable for xeriscaping

Average Water Needs; Water regularly; do not overwater

Self-sows freely; deadhead if you do not want volunteer seedlings next season

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

Seed Collecting:

Allow seedheads to dry on plants; remove and collect seeds

Regional

This plant has been said to grow in the following regions:

Booneville, Arkansas

Edwardsville, Illinois

Saint Charles, Illinois

Wauconda, Illinois

Foxboro, Massachusetts

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

Kalama, Washington

Lynnwood, Washington

Poulsbo, Washington

Seattle, Washington

Eau Claire, Wisconsin

Menasha, Wisconsin

show all

Gardeners' Notes:

5
positives
0
neutrals
0
negatives
RatingContent
Positive

On Apr 4, 2008, Malus2006 from Coon Rapids, MN (Zone 4a) wrote:

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 ground. More uncommonly sold compare to C. montana. A common name is Tall Bachelor's Button.

Positive

On Jun 11, 2007, bakingbarb from Lynnwood, WA wrote:

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 dig up the baby plants, just make sure to get some roots with it.

Positive

On Jul 4, 2006, bigcityal from Menasha, WI (Zone 5a) wrote:

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

Positive

On Aug 10, 2005, flowercrazy39 from Manchester, NH wrote:

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

Positive

On Jul 23, 2004, peonylady from Anchorage, AK wrote:

Our USDA zone is usually 3, although we have had
several favorable winters lately. The Persian Cornflower
has performed very well, has not reseeded agressively here,
grows strongly, may need dividing every third year to keep it
in bounds, color and form is very attractive, and it is
especially nice to photograph.