Does Bleach Kill Weeds? How To Use Bleach As A Weed Killer.

Does bleach kill weeds?

In a nutshell, YES, bleach does kill weeds.

Read this article thoroughly before you start spraying pesky weeds with bleach.

As well as being a great spot cleaner, the use of bleach as a weed killer is also quite effective, just add some undiluted bleach to a spray bottle and away you go. Be aware, it is not intended for use as a herbicide. Chlorine Bleach was created in 1785 by French scientist Claude Berthollet as a way to remove colour from fabrics 

Almost everything is destroyed by bleach,  is there a reason why this wouldn’t kill weeds?

Its safety factor is more important, it might be a powerful herbicide, but that’s not what bleach is designed for.

How safe is it to use bleach weed killer to kill weeds permanently?

In a nutshell, no it’s not safe. Using bleach is extremely hazardous, it affects the soil health and leaves harmful traces of chemicals everywhere it is sprayed.

If you want to avoid potential groundwater contamination, try vinegar instead. In addition to your pets and local wildlife, it can also harm the critters living in your soil.

Bleach could permanently damage the soil quality and ecosystem surrounding you if used consistently over many months or years. In the event of enough bleach being used, nothing will want to grow, causing major damage to the environment.

Depending on where you live you may not be allowed to use bleach as a herbicide in your region. Your local authority should be able to assist you.

How does it work? How does bleach kill weeds?

Because bleach is so terrific at cleaning and disinfecting, it’s also an excellent herbicide as well. In addition to humans, plants and animals are also poisoned by bleach. In the same way that it would destroy any living organism. It works because it soaks into the roots of a plant.

Bleach will increase the pH level of soil area where it’s poured and nothing can grow on that area for a considerable length of time (often several months) which can make your flower bed useless.

Some instructions on using bleach as a herbicide:

The following instructions should be followed if you want to use bleach as a weed killer:


  • Safety gloves and eye protection should be worn at all times.
  • Prevent accidental spraying by using on a calm day.
  • Pull out the dead weeds after a few days.
  • To test its effectiveness, try it out a little.
  • Children and pets should not be allowed in the area.


  • Overuse.
  • Don’t let children or pets near it until it’s dry.
  • Do not spray on vegetation you hope to keep.
  • Apply to lawns or crops that are edible.
  • Whenever possible, use near water sources.
  • Environments containing aquatic life.
  • Use on a day when rain is forecast.
  • Combine with other chemicals
  • Don’t spray any desirable plant or they may die 

Chlorine Bleach can be used either diluted and sprayed or undiluted and smeared between cracks in paving, slabs, on a gravel driveway or other hard surfaces to kill weeds growing there. It will kill weeds permanently.

Choose a day that is warm and calm with no forecast of rain, in the event of rain, bleach can infiltrate other plants and areas of your garden, killing them. During the spraying process, bleach can be blown onto plants or other people by the wind.

How effective is it to kill weeds?

Using bleach on weeds is an effective herbicide. Weeds will be killed by it, almost all small weeds are killed by bleach. Unlike larger or invasive ground plants like Ivy, Brambles and Knotweed, it won’t work on them. 

Bleach will destroy weeds by seeping into the roots of weeds, you won’t be able to grow on soiled surfaces, and you’ll have to wait several months before your garden soil is ready to plant in.

Do you recommend it’s use?

We, among most others, recommend against its use.

Bleach kills weeds however when it is overused, it can kill trees, plants, and insects not just weeds. Other serious environmental effects can result from it, such as seeping into the groundwater, in some places it is illegal as well.

If you need to use it, make sure you use it sparingly and only in cracks in your paving. Consider using one of the following alternatives for a safer, smarter and more effective solution.

What is the alternative to bleach?

Bleach is a hazardous chemical that is harmful, the main ingredient of household bleach is 3% to 6% Sodium Hypochlorite

The use of bleach as herbicide works well when used sparingly, though there are many better, safer options out there:

To get rid of weeds, assuming you do not mind using chemicals, you might as well use a commercial weed killer. When used correctly, they can be used safely as herbicides provided the instructions are followed and the label is read.