Reynoutria, Asian Knotweed, Japanese Knotweed 'Devon Cream'

Reynoutriajaponica

Species
japonica (juh-PON-ih-kuh)
Synonym
Fallopia japonica
Sun Exposure
Sun to Partial Shade
Light Shade
Foliage
Grown for foliage
Good Fall Color
Veined
Height
24-36 in. (60-90 cm)
36-48 in. (90-120 cm)
4-6 ft. (1.2-1.8 m)
Spacing
24-36 in. (60-90 cm)
Hardiness
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)
USDA Zone 10a: to -1.1 °C (30 °F)
USDA Zone 10b: to 1.7 °C (35 °F)
Bloom Color
White/Near White
Bloom Time
Late Spring/Early Summer
Mid Summer
Late Summer/Early Fall
Other Details
Category
Perennials
Shrubs
Water Requirements
Average Water Needs; Water regularly; do not overwater
Foliage Color
Where to Grow
Bloom Characteristics
Bloom Size
Other details
May be a noxious weed or invasive
Soil pH requirements
Patent Information
Propagation Methods
Seed Collecting
N/A: plant does not set seed, flowers are sterile, or plants will not come true from seed
Regional

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

Ben Lomond, California

Boulder Creek, California(2 reports)

Calistoga, California

Clayton, California

Fairfield, California

Mount Prospect, Illinois

Saint Paul, Minnesota

Media, Pennsylvania

Wilkes Barre, Pennsylvania

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Gardener's Notes:

1
positive
0
neutral
1
negative
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C
ROSLINDALE, MA | April 2016 | negative

The sale, purchase, planting, and cultivation of all forms of this species are illegal in my state and seven others, because of the damag...Read More

N
Madison, WI | July 2004 | positive

I've grown three of these plants in Southern Wisconsin for 4 years, two in partial shade and one in sun. The plant in full sun is larger...Read More

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