Japanese knotweed

Reynoutria japonica

Reynoutria

Polygonaceae

Native Plants

Zone 4–10

🐾 Pet-Safe

🌱 Beginner Friendly

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.

Care Requirements

Care Level

Low

Sun

Partial Sun

Water

Moderate

Growth Rate

Moderate

Mature Height

24″ – 60″

Soil

loam

Life Cycle

Perennial

Spacing

24″

Watering Schedule

Every 10-14 Days • Deep Watering Until Soil Is Saturated, Then Allow To Dry Between Waterings

Soil pH

5.5 – 6.5

Temperature

-30° – 95°F

Mature Spread

up to 48″

Root Depth

Medium

Foliage

Medium

Propagation: Seed

Ecology & Origin

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

Safety & Use

⚕ Medicinal

🐾 Pet-safe

Sources

Data: trefle, usda

Image: trefle.io — Taken Sep 5, 2021 by The Sandgrounder (cc-by-sa)

Hardiness Zones

Check your zone:

Available From (0)

No nurseries currently have this species in stock.