broadleaf weed · perennial
Fallopia japonica
Fast-growing stems 3–10 feet tall with broad, triangular leaves and small white or greenish flowers in late summer.
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Japanese knotweed has rhizomes up to 10 feet deep — digging alone almost never works. Inject or spray glyphosate into cut stems in fall. This is a multi-year project. In some areas, professional removal is recommended.
Glyphosate is most effective; apply repeatedly to foliage in late summer into fall when plants are translocating carbohydrates to roots. Herbicide alone often requires multiple seasons.
Prevent any fragments from spreading; contain and remove root systems entirely if possible.
Prevent any fragments from spreading; contain and remove root systems entirely if possible.
BioAdvanced All-In-One Weed & Feed (22-0-4)
Scotts Turf Builder Southern Triple Action
Scotts Turf Builder Southern Triple Action
Scotts Turf Builder Triple Action1
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Measure my lawn — it's free →Fast-growing stems 3–10 feet tall with broad, triangular leaves and small white or greenish flowers in late summer.
Herbicide spray. Japanese knotweed has rhizomes up to 10 feet deep — digging alone almost never works. Inject or spray glyphosate into cut stems in fall. This is a multi-year project. In some areas, professional removal is recommended.
Knotweed (Japanese and Giant) is rated hard to control. It usually requires multiple applications and a consistent plan.
Prevent any fragments from spreading; contain and remove root systems entirely if possible.