Ornamental Onion
Allium thunbergii 'Ozawa'

Family: Alliaceae
Genus: Allium (AL-ee-um) (Info)
Species: thunbergii (thun-BERG-ee-eye) (Info)
Cultivar: Ozawa

Category:

Bulbs

Perennials

Height:

6-12 in. (15-30 cm)

Spacing:

6-9 in. (15-22 cm)

Hardiness:

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)

USDA Zone 9a: to -6.6 C (20 F)

USDA Zone 9b: to -3.8 C (25 F)

Sun Exposure:

Sun to Partial Shade

Danger:

N/A

Bloom Color:

Fuchsia (Red-Purple)

Bloom Time:

Mid Fall

Foliage:

Herbaceous

Other details:

Average Water Needs; Water regularly; do not overwater

Soil pH requirements:

Unknown - Tell us

Patent Information:

Non-patented

Propagation Methods:

By dividing the rootball

Seed Collecting:

Unknown - Tell us

Regional

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

Park Ridge, Illinois

Roslindale, Massachusetts

Uxbridge, Massachusetts

Lisbon, New Hampshire

Clinton Corners, New York

Hendersonville, North Carolina

Wilkes Barre, Pennsylvania

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Gardeners' Notes:

1
positive
0
neutrals
0
negatives
RatingContent
Positive

On Jan 20, 2014, coriaceous from ROSLINDALE, MA wrote:

I've grown the cultivar 'Ozawa' for many years. It's a tough, easy plant, valuable for its rich purple flower color, long late season of bloom, and brilliant orange fall foliage color. It clumps up very quickly without being at all aggressive. I've never seen a self-sown seedling.

Though it's a bulbous plant, this species does not go dormant before late fall. The leaves stay healthy, slowly turning a luminous orange, up till Thanksgiving, or later if not hit by hard frost.

Division of the clumps is the easiest way to increase a planting. A single bulb forms a good tight clump in one season. Clumps can be divided any time of year the ground is workable.

This cultivar produces flower scapes about 9" tall in midsummer, but the buds don't begin to ... read more