Will Bleach Kill Bushes (+ 5 “How To” Tips)

Bleach will kill all manner of small plants, including bushes. However, most horticulturalists and gardeners will recommend against its use for many reasons, most of which centered around the danger it poses to the environment and to people.

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Nothing seems to spruce up a nice garden or a dull street quite like a few lovely bushes, but if you’re in a situation where you would consider these little ankle growers to be annoying weeds in your outdoor space, you may have struggled in getting rid of them. Perhaps you’ve considered chemical warfare – if you have, you may be wondering whether the bleach you have under the kitchen sink will do the trick.

Bleach is an effective herbicide and will kill all manner of small plants – but bleach is an effective killer period and will kill all manner of small anything. But if you truly insist on using bleach to wage war on the stubborn shrubbery, then there are safer ways to go about it, which we will go on to talk about later. But first, a little chemistry lesson on its murder method.

Plastic bleach bottle of household detergent lying on white background

Related Reading: Does Pressure Washing with Bleach Kill Grass?

How Does Bleach Kill Bushes?

Most people are very aware of bleach being toxic to humans; the reason it can kill plants is actually because of the same reason: bleach has an incredibly high PH. Now, in humans, this causes chemical burns, and whilst it doesn’t leave a burn on plants the same way, it’s this alkaline PH that makes it deadly.

Most plants have a very specific PH range in which they thrive, too acidic or too alkaline and they will wither and die. When bleach is poured into the soil, it drips its way all the way down into the ground and kills the plant via the roots.

A nasty side effect of pouring bleach in the soil is that when it finally begins to break down, it creates salt as a by-product, which usually will then continue to make the soil uninhabitable for plant life due to its osmatic effect – which in layman’s terms means that salt draws water out from the roots and prevents any plants from drinking until they die of thirst.

Keep in mind, if you are trying to kill a singular bush with bleach, then it will be effective (even if not recommended) but if you are trying to kill plants with dense root networks, then the bleach will not be effective; you’d have to pour so much bleach on the soil to eradicate every root in its network that the garden you sprayed with bleach would not grow anything for months. For this exact reason, some plants bleach will be ineffective against are:

  • Ivy
  • Brambles
  • Knotweed

So be warned, bleach is also effective a weed killer and reckless usage of it will make most gardens unable to grow anything for months until the chemicals have not just broken down, but completely washed away.

How to Use Bleach to Kill Bushes

If you have read until this point and are still thinking about using bleach in your garden, then there are some tips that gardeners recommend you use to make it safer.

1. Restrict Its Usage

This one is obvious but needs to be mentioned. As stated before, reckless use of bleach can effectively kill the soil of a garden for months. Try to restrict any use of bleach to cracks in paving and use when it can affect as few other plants as possible. Use it a little at a time to test its effectiveness – if it’s ineffective on the bush as a whole, then it would be a slap in the face to ruin every other plant in your garden in the experiment.  

2. Prevent Bleach From Spreading

As with any herbicide, you want to affect the outer environment as little as possible aside from the target plants, so if you’re going to use something as harmful as bleach, use it on as calm and sunny a day as you can.

The logic here is that if you’re spraying bleach on a windy day, the wind will carry the bleach to unwanted areas, and if rain is forecasted later, then the bleach will be carried through the soil by the water. Another thing you can do to prevent its spread is to wait a few days before pulling out the dead weeds.

3. Protect Your Family

Remember: bleach is incredibly toxic to people and pets as well! When you are using bleach, always wear safety gloves and eye protection at a minimum to protect yourself, and do not let any loved ones, be they human or fur babies, near the area where you sprayed the bleach until you know for a fact that it is dry.

4. Do Not Spray Anywhere Near Water

As mentioned in a previous tip, bleach can leach out into the greater environment through the water. So, naturally, do not, under any circumstances, use bleach near any water sources, or aquatic environments. It doesn’t matter how annoying that bush next to your pond is – don’t do it!

5. Do Not Mix With Other Chemicals

This is another biggie. Bleach is extremely toxic on its own, but some people lacking in the chemistry department may still think that one super strong chemical plus another super-strong chemical makes for a super, duper strong chemical when that thought couldn’t be more dangerous.

Bleach does not play well with others as a rule of thumb, with some of the grisliest results being:

  • Bleach and Ammonia – Ammonia is a common ingredient in many herbicides, which means it’s dangerous to attempt bleach after trying a different herbicide if you don’t enjoy your lungs being full of chloramine.
  • Bleach and Vinegar – Some websites recommend vinegar solution as a gentler and more natural herbicide but pouring bleach in any areas you have also poured vinegar will create chlorine gas. You know, the gas used in WW2 gas bombs to kill people? Yeah, you want to avoid that one.
  • Bleach and Alcohol – Booze is not recommended as a herbicide, but sites will recommend rubbing alcohol as a pesticide. Again, if you have ever tried this, bleach afterwards is going to be a huge problem. This time, it’s toxic chloroform you’ll need to worry about.

If none of this has put you off using bleach in your garden to kill unwanted bushes, then bleach can be used either diluted and in a spray bottle, or undiluted and poured into cracks between hard surfaces, such as slabs or paving.

Related Reading: Can You Use Bleach to Pressure Wash a House?

Conclusion

Bleach can be used to kill bushes, but it is an indiscriminate killer of plants and animals alike, and if bleach gets into the soil, then it’s likely nothing will be able to grow in it for months due to its high PH and salt by-products when it breaks down.

If you must use bleach as a herbicide, then use protection, keep your family away, use sparingly, never mix with other chemicals or use near a water source of any kind, and finally, use on a calm day where it can dry and not be spread into the external environment by wind or rain.