Japanese Knotweed Removal & Treatment in Seattle
By Lee's Product Team August 28, 2025

Japanese Knotweed Removal & Treatment in Seattle

Landscaping

Japanese Knotweed Removal

Japanese knotweed is one of the most aggressive invasive plants in Seattle. It grows fast, spreads underground, and can damage fences, patios, foundations, and even concrete. Once it takes hold, this weed is almost impossible to get rid of without the right approach.

At Lee’s General Landscaping, we specialize in safe, effective knotweed removal for Seattle homeowners. Our team knows the local regulations, the timing, and the best techniques to stop knotweed in its tracks—and keep it from coming back.


Why Knotweed is Such a Problem in Seattle

  • Spreads underground: Its rhizome roots can travel 20 feet or more and resprout from tiny fragments.
  • Damages property: Knotweed pushes through asphalt, concrete, and foundations, creating costly repairs.
  • Hard to kill: Cutting or mowing only makes it worse—each cut encourages new shoots.
  • Regulated plant: Knotweed is a listed noxious weed in King County, which means it must be controlled properly.

Our Proven Knotweed Removal Process

  1. Site Evaluation
    We inspect the infestation and surrounding area to understand how far knotweed has spread.
  2. Cutting & Containment
    We carefully cut and manage the plant growth without spreading fragments to new areas.
  3. Targeted Herbicide Treatment
    In late summer and fall, when the plant draws energy into its roots, we apply professional-grade treatments that move deep into the rhizomes.
  4. Follow-Up & Monitoring
    Knotweed removal is rarely a one-time job. We schedule follow-ups to make sure the infestation weakens year after year until it’s fully under control.

Why Choose Lee’s General Landscaping?

  • 🌱 Local Experts – We’ve handled knotweed removal across Seattle’s neighborhoods, from backyard patches to hillside infestations.
  • 🛠 Safe & Effective Methods – We use techniques designed to target knotweed without harming the rest of your yard.
  • 📋 Seattle Regulations – We know King County’s noxious weed rules and help you stay compliant.
  • 💪 Full-Service Care – Beyond knotweed removal, we can re-landscape the cleared area with mulch, native plants, or hardscape features to give your property lasting beauty.
See also  Garden Animals: Entomology for Seattle Homeowners

Get Knotweed Under Control Today

Japanese knotweed only gets worse the longer it’s left untreated. Don’t waste time with DIY methods that don’t work. Call Lee’s General Landscaping and let our Seattle team tackle knotweed at the root.

Contact us today for a free estimate and protect your home from one of the toughest weeds in Washington.

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