trefle.io · Taken Sep 5, 2021 by The Sandgrounder (cc-by-sa)
Polygonaceae
Japanese knotweed
Reynoutria japonica
Also known as Reynoutria hachidyoensis, Polygonum cuspidatum var. uzenense, Reynoutria uzenensis, Polygonum zuccarinii
Native Plants · Invasive · Hardy · Bamboo-Like · Screening · Rhizomatous · Vigorous · Edible-Shoots · Medicinal
Japanese knotweed is extremely hardy and requires minimal care once established. It thrives in most soil conditions and spreads rapidly through underground rhizomes. Note that this plant is considered highly invasive in many regions and should be grown with extreme caution.
Growing conditions
The details behind the basics
- Daily light
- 6 hours
- Watering
- Deep watering until soil is saturated, then allow to dry between waterings · Every 10-14 days
- Maintenance
- Low
- Soil
- loam
- Soil pH
- 5.5–6.5
- Temperature
- -30°F to 95°F
- Cycle
- Perennial
- Propagation
- Seed
Hardiness
USDA 4a-10b
Form & growth
Mature size and habit
- Mature height
- 2 ft – 5 ft
- Spread
- 4 ft
- Spacing
- 24 in apart
- Growth rate
- Moderate
- Root depth
- Medium
- Flowers
- No
- Foliage
- Medium
Ecology & origin
Where it belongs and what it brings
- Native to
- Alabama, Alaska, Amur, Arkansas, Austria, Baltic States, Belgium, British Columbia, Bulgaria, California, Central European Rus, China North-Central, China South-Central, China Southeast, Colorado, Connecticut, Czechoslovakia, Delaware, Denmark, District Of Columbia
- Attracts
- Bees, Butterflies
Sources: trefle, usda
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No nursery lists Japanese knotweed right now.