How to Properly Dispose of Japanese Knotweed for Good

Japanese knotweed is an invasive plant that can quickly take over gardens and yards. Getting rid of it takes persistence and using the right disposal methods to prevent further spread. Learning the proper ways to dispose of Japanese knotweed is key to successful removal.

Why Japanese Knotweed Needs to Go

With bamboo-like stems and pretty cream-colored flowers, Japanese knotweed can seem attractive at first glance. However, this plant is one of the most aggressive invaders in North America and the UK. It’s even considered an ecological threat.

Here are some key reasons why Japanese knotweed must be controlled:

• It grows very rapidly, as much as 4 inches per day. This allows it to quickly crowd out native plants.

• The roots can spread outward up to 20 feet and grow 10 feet deep. They are difficult to fully remove.

• It can push through concrete and even cause damage to buildings, driveways, and other structures.

• Many areas have laws restricting Japanese knotweed due to its destructive capabilities It’s even regulated as “controlled waste” in the UK.

Clearly, allowing Japanese knotweed to thrive leads to major issues down the road. That’s why it’s so important to get rid of it and prevent further spread.

Start by Cutting Down the Canes

Cutting the stalks or “canes” of Japanese knotweed can help slow its growth when done properly, Here are some tips

• Use loppers or pruners to cut the canes to the ground. Try to remove every bit above ground.

• Put the cut pieces in heavy garbage bags immediately to contain them.

• Cutting works best in summer when the plant is actively growing. Cut once per week to really slow it down.

• Combine cutting with other methods like herbicide application for best results.

Cutting alone won’t kill Japanese knotweed. But it can help weaken and control it when done persistently. It also stops the plant from spreading seeds.

Apply Herbicides to Kill the Roots

Since the roots of Japanese knotweed run so deep, the only way to kill the plant is by using a systemic herbicide like glyphosate (Roundup). The chemical will penetrate to the roots and destroy the entire plant.

Follow these guidelines when using herbicide:

• Spray on a dry, calm day to avoid drift. Wear protective clothing.

• Apply during summer and early fall when the plant is actively growing.

• It may take several applications a week apart to fully kill the plant.

• Leave sprayed plants in place for 1 week before removal so the herbicide can work.

• Always read and follow label directions. Use caution when applying near water sources.

Herbicides provide the strength needed to successfully get rid of invasive knotweed. Repeated applications are key.

Dig Up the Root System

Once the aboveground parts of the Japanese knotweed plant have died back after cutting or spraying, the next step is to dig up the root system. This helps prevent any remaining roots from resprouting.

Follow these pointers when removing the roots:

• Use a shovel, pickaxe, or pruning saw to remove roots. They can run very deep so dig down at least 3-4 feet.

• Remove every piece of root and rhizome you find. Even small fragments left behind can grow into new plants.

• Consider installing a root barrier after removal, especially near hardscapes like fences or buildings.

• Removing the roots is hard work and may not be 100% effective, but it should help slow down the plant’s return.

Persistence pays off when digging out knotweed roots. Just make sure to get every piece, no matter how small.

Dispose of Knotweed Carefully

Perhaps the most crucial part of knotweed removal is how you get rid of the plant parts after cutting or digging. Careless disposal can enable spread to new areas. Here are smart disposal methods:

Drying Out

• Place all plant parts, including roots and canes, in heavy black plastic bags.
• Seal the bags fully and leave them in direct sun for at least a week. The heat helps destroy the plant cells.
• Once dried out, the bags can be disposed of in regular household trash pickup.

Burning

• Burning is effective but check local ordinances first. Most communities restrict outdoor burning.
• Use a metal burning barrel and burn the knotweed until it’s completely ashes.
• Bury the ashes at least 3 feet underground.

Landfills

• Not all regular landfills accept Japanese knotweed due to its invasive nature. Always call ahead.
• Special waste disposal sites and waste transfer stations are equipped to incinerate knotweed properly.
• Clearly label the bags as containing Japanese knotweed so the landfill is aware.

Avoid Composting

Never put any part of the Japanese knotweed plant into your home compost pile. It can quickly re-sprout from even tiny remnants.

Stop an Infestation Before It Starts

Prevention is also key in the battle against Japanese knotweed. Follow these proactive measures to avoid issues:

• Learn to identify Japanese knotweed so you can spot it early. Look for hollow, bamboo-like stems and shovel-shaped leaves.

• Monitor your property frequently, especially along fence lines, drainage ditches, and low-lying areas prone to invasion.

• Never purposefully purchase or transplant Japanese knotweed. Many online sources sell it unaware of the risks.

• Clean equipment, tools, footwear, and tires after working in knotweed-infested areas to avoid transporting pieces elsewhere.

Staying vigilant allows you to get a jump on any potential knotweed growth before it gets out of control. Your quick action can pay off.

Be Patient and Persistent

Completely removing Japanese knotweed takes time, dedication, and using multiple control methods together. There is no single easy fix. Just stay focused on the goal and don’t allow the plant to ever fully recover.

With persistence and the right techniques, you can successfully rid your property of the Japanese knotweed menace. Careful disposal prevents it from taking root elsewhere. Stopping this destructive invader in its tracks restores your yard to its natural beauty.