Best Root Killer for Sewer Lines (2023 Update)

If DIY remedies don’t help much, you’re gonna need the best root killer for sewer lines to tackle the issue.

According to the U.S. Department of Agriculture study, tree roots caused more than 50% of all sewer blockages. It’s nothing strange shrubs and trees grow mostly around sewer lines (where oxygen, water, and other nutrients roots crave reside).

Thus, at a certain moment, roots will start invading the pipes and cause blockages, and there are very few steps to take when things start getting out of control.

At this point, unusual gurgling sounds will start coming out of your drain and the drainage will get slower and slower with every flush. If that’s already the case in your household, it’s safe to say your sewer line is in danger.

You’d better act quickly before the issue becomes critical, and the first step to take is to get – a root killer for trees!


Roebic FRK-1LB Foaming Root Killer, Clears Pipes and Stops New Growth, Safe for All Plumbing, 1...
Zep Root Kill - 2 lbs (Case of 4) ZROOT24 - Drain and Septic Care, Professional Strength Formula
Root Destroyer – 2lbs of Pure Copper Sulfate Crystals - Root Killer for Sewer & Pipe Lines- Stops...
Best Value For Money
Roebic FRK-1LB Foaming Root Killer, Clears Pipes and Stops New Growth, Safe for All Plumbing, 1...
Best Value For Money

A root killer for trees can help you prevent roots from creeping into your sewer pipes and endangering your septic system even if everything seems normal down there.

How does this product work, how often should you use it, and what are the best picks in this category? String along to find out!

What Is the Best Root Killer for Sewer Lines?


Which one to pick – foaming or a copper-based root killer for sewer lines? How can you know whether it can cause potential environmental harm? How to use this product at all? We’ve done the hard work for you. Here’s a list of the 5 best root killers for sewer lines (and all the details you should know about each).


1. Roebic FRK-1LB

Roebic FRK-1LB Foaming Root Killer, Clears Pipes and Stops New Growth, Safe for All Plumbing, 1...
  • KILLS ROOTS IN SANITARY SEWERS: Roebic FRK-1LB Foaming Root Killer kills roots in sanitary...
  • FOAMS ON CONTACT: Exclusive Roebic Root Killer formula, which does not contain copper,...
  • SAFE FOR ALL PLUMBING: Foaming Root Killer is safe for all types of plumbing and will not...

Roebic FRK-1LB is a foaming root killer specifically formulated to help homeowners get rid of severe and recurring root problems in a walk. Not only does it kill the existing roots in your sewer system but it also prevents new root growth.

This agent is safe for all plumbing as it contains copper instead of dichlobenil that efficiently destroys roots without damaging the surrounding trees.[3]

How to use this product? Fill the pipeline with the Roebic FRK-LB1 granular concentrate, flush the water down the system, and it will start foaming right away. You can also use this formula to maintain your system and prevent clogs and breakouts roots can make.


  • Works wonders with recurring root problems;
  • Completely safe for the surrounding trees;
  • Instant foaming;
  • Typically takes 4 to 6 hours to work.


  • Florida banned this product under the pretext it is not safe for septic systems;
  • A few customers complained they received an expired product.

2. Roebic K-77

Roebic K-77 Root Killer for Sewer and Septic Systems, Clears Pipes and Stops New Growth, Safe for...
  • KILLS ROOTS IN SEWER AND SEPTIC PIPES: Roebic K-77 Root Killer clears existing roots and...
  • PREVENTS RE-GROWTH: The K-77 copper formula chemically kills roots at the point of entry...
  • SAFE FOR ALL PLUMBING: Root Killer is non-corrosive and safe for all types of plumbing and...


Another great product from the same brand, Roebic K-77 is the ultimate root killer for sewer lines.

What’s more, hundreds of customers rave about the Roebic K-77 as the best root killer for sewer lines.

This copper sulfate formula destroys nasty roots at the entry point into the pipe and prevents new ones from growing and clogging your systems.

Safe for all types of plumbing and non-corrosive, Roebic K-77 works without destroying or harming surrounding trees, pipes, or septic tanks so you can use it worry-free.

Yet, how to use it exactly? Pour 1/3 of the bottle into the toilet bowl (never through a sink or tub), flush it, and do not flush for the next several hours. Ideally, you will do this before going to bed so the formula has enough time to take effect.

In case of a serious blockage, it might take from 2 to 7 days for the product to work. Use it every 6 to 12 months to maintain your sewer system properly.


  • Provides relatively quick results;
  • Destroys roots at the entry point;
  • Comes in a large bottle;
  • Does not damage plumbing.


  • The bottle might not be properly sealed so be careful upon receiving the product

3. Roebic FRK Foaming Root Killer

Roebic FRK Foaming Root Killer, 1-Pound (2 Pack)
  • Packaging may vary
  • Use quarterly to kill roots in drain pipes
  • Active Ingredient coats roots causing them to dry, get brittle, and break into little...

This Roebic Foaming killer is one of the most efficient products in this category.

This powerful formula dehydrates roots and prevents their further growth. Once the roots get dehydrated, they got brittle and way easier to flush out of the system.

It doesn’t contain copper sulfate (which some states have banned), meaning – only the roots are in danger, while your tree is completely safe.

How to use Roebic FRK Root Killer ?

Put it into the sewer line. Flush slowly with 1-3 gallons of water. After that try not to flush drain for 4 to 6 hours.

This procedure should be done once a year.



  • Great for maintenance
  • Can be used for septic systems
  • Kill all kinds of roots


  • The contents of the second bottle can be hardened
  • Takes time to work

4. Zep Root Killer

Zep Root Kill - 2 lbs (Case of 4) ZROOT24 - Drain and Septic Care, Professional Strength Formula
  • For direct use in household or residential sewer systems, septic tanks, leach lines, and...
  • Professional strength: Zep Root Kill is a pro-strength, granular formula that is highly...
  • Safe for trees: the drain root killer effectively gets rid of unwanted tree roots in pipes...

If you are on the hunt for a product that can provide immediate results, Zep root killer could be the one. This granular formula boasts the ultimate strength and efficiency and is capable of dissolving tree roots in your sewer system and pipes almost in one-two-three.

Not only does it help you get rid of the unwanted visitors in your sewer system but it does not harm the surrounding shrubs and trees (woohoo!). Also, this product is safe to use in sewer systems, leach lines and line pipes, and septic tanks.

How to use the Zep root killer? Pour one-quarter of the product in your toilet, flush it, and refrain from flushing in for the next 8-10 hours. Use this root killer for sewer lines 2 times per year to keep the roots away for the good.


  • Super-efficient root dissolving properties;
  • Promotes fungus control;
  • Safe on pipes;
  • Comes in a large 2lb bottle that can last for a while.


  • Banned in California.

5. Sanco Industries Root Destroyer

Root Destroyer – 2lbs of Pure Copper Sulfate Crystals - Root Killer for Sewer & Pipe Lines- Stops...
  • Made up of copper sulfate crystals that will kill invasive septic and sewer pipe roots...
  • Root Destroyer will temporarily reduce bacterial action, but will return to normal...
  • Only roots inside the leach line will be killed. Do not apply through sink or tub drains.

Sanco Industries root destroyer is a powerful formula that invades and kills tree roots and re-establishes the optimal flow in your sewer system with ease. It takes 3 to 4 weeks for the product to eliminate all the roots from the system, while you’ll notice a gradual flow increase within no more than 72 hours. Oh, and, don’t worry – this root destroyer won’t harm your tree, only the roots.

How to use the Sanco Industries root destroyer? Pour about 0.5 lb into the toilet, flush it, and give it some time to act. Because it comes in a large 2-lb bottle, you can use it 4 times a year, which is more than enough to keep the roots away.

Sanco Industries root destroyer is safe for use for septic tanks while you can treat leach line pipes with it as well to achieve a complete root control.


  • Easy to apply;
  • Odor-free;
  • Provides long-lasting protection;
  • Cost-effective


  • Might take slightly more time to work than some other products on our list.


How Does a Root Killer for Trees Work?

Root killers containing metam sodium and copper sulfate [1] – a strong substance that poisons the roots in your sewer system and prevents their further expansion. Note that a root killer does kill roots, not the tree, and you would have to remove them from your sewer system somehow if you want to remove blockages.

Does Root Killer for Trees Work?

It does! A root killer for trees can effectively eliminate the roots that have been sitting in your sewer line pipe for months, even years! However, keep in mind you would still have to repair the damage roots made in your pipe (yes, even if it is a small crack) and put an end to potential leaks. Otherwise, the soil around your home can get easily eroded [2] and cause irreversible damage (f.e. affect the foundation of your house).

How Often to Use a Root Killer for Trees for Preventive Maintenance?

Use a root killer for trees every 30-60 days to inhibit root growth. Most root killers are safe for both humans and animals so you can continue using this product routinely to prevent damage to your sewer system.

How Long Does a Root Killer for Trees Take to Work?

Depending on the severity of the problem and the exact spot in the system where the roots are making blockages, a root killer may take 2 days to 2 weeks to work.

Read Also: Can Tree Roots Penatrate PVC Pipe

Bottom Line

Clogged drains and sewer pipes – tree root invasion is everything but fun! Leaving this issue without any further action can make your whole drainage system collapse (and we think you don’t want that, right?). So, instead of being ignorant, take immediate action and spare yourself a headache. To set your plan on the right foot, pick a product from our list that seems like the best root killer for sewer lines and go get those roots out of your system.