Does dish soap kill grass if you use it in order to kill pests, fungi, and weeds from your lawn? Yes, when used carelessly without dilution, this soap will end up in your grass.

Dish Soap Can Kill Grass

That does not mean you can’t use soapy water for several lawn care procedures. Read this guide to learn when and how to use soap correctly without killing your precious grass.

Does Dish Soap Kill Grass?

💥 Dish soap kills grass only if it contains chemicals like sodium lauryl sulfate or bleach and is used undiluted. These soaps are dish detergents that break down fats and oils from household dishes we eat. Naturally, they cannot be made from very harsh chemicals.


– What Undiluted Dish Soaps Do To Grass

Applying dishwashing soap directly to the grass blades will strip them of their protective layer of wax. This is because most soap’s chemicals are meant to disintegrate fats and oil

Once their protective layering is gone, the grass blades are unable to retain any moisture. They lose their plump nature and become brittle. Their color also changes from green to a sickly brown or yellow. The damage is more pronounced when the weather is hot and dry. In severe cases, the grass might die of damage altogether.

The damage depends on how much soap you use, in what concentration, and for how long. Naturally, undiluted soap that is already harsh for a long time will damage grass more than an accidentally spilled dish soap in one part of the lawn.

– What Dish Soaps Do To Grass Seeds

Seeds are extremely sensitive and will only germinate under perfect conditions. Naturally, applying even mild chemicals to them in the form of dishwashing soap will damage their outer covering, and they will die.

Grass Seeds on the Field

That is the sole reason you must be extra careful about using soaps when the grass is self-seeding. For warm-season grasses, this is around early spring, whereas, for the cool growing grasses, seeding usually occurs in late fall.

– Using Diluted Dish Soap As A Pesticide

Yes, you can use dishwashing liquid soap in diluted form to get rid of harmful pests from your lawn. Proceed by adding two tablespoons of vegetable oil and one tablespoon of this soap to one gallon of water. Mix well and put this DIY mixture in a bottle with a spray nozzle.

Spray your grass lightly, using this mixture once every week. Ensure all lawn corners get covered and only spray from a reasonable distance. Please wait one hour for the mixture to be effective, and then wash it off with water. Repeat every week until you feel there has been an adequate reduction in your lawn’s pest population.

This soapy water mixture works by stripping the protective layer from the bodies of all common lawn pests such as grubs, mealybugs, snails, etc. Either these bugs will get irritated and stop visiting your lawn, or they might die altogether. 

Just don’t use this mixture more than once per week or with more quantity of soap; otherwise, your grass will start dying just like the pests. 

– Go for Insecticidal Soaps Instead

Insecticidal liquid soaps are manufactured specifically for removing harmful bugs from your lawn. Unlike dishwashing soaps, they are made from soap salts and work only when wet. This soap will kill lawn bugs such as grubs, aphids, and spider mites but will not harm useful biological agents such as ladybirds or beetles.

Go to your local super marker, and several brands make these soaps, mostly in liquid formulations. They come in portable spray bottles and tend to be reasonable in price. Check the label on the back to ensure it says ‘safe for use on grass.’

Using Insecticidal Soaps on Grass

Before using this soap on the entire lawn, we suggest you do a patch test first. Spray on a tiny section of the lawn with a moderate quantity of soap. Wait for 24 hours to see if the grass shows any adverse reaction.

If your grass shows that it can tolerate this spray, then go ahead for a full spray. It will only work when wet, so schedule it right after you water your entire lawn.

Then spray a generous amount of insecticidal soap over the grass. Reapply every four to seven days per the guidelines given by the soap manufacturer, and you will soon see a marked decrease in the pest population on your lawn.


– Using Dish Soap to Kill Weeds

Yes, you can use this soap in a DIY formulation to make an organic pesticide that will also kill fungus and weeds. The key here is to use only a tolerable quantity of soap that will not irritate the grass.

Proceed by taking one gallon of clean water and adding one whole cup of salt to it. Just one tablespoon of soap and your weed-killing mixture is ready.

Please remember that we are not talking about common household vinegar here, as it is too mild to exert any real effect. What you need is store-bought vinegar with a concentration of 20 percent or above.

Killing Weeds Using Dish Soaps

After your mixture is ready, store it in a plastic spray bottle with a nozzle attached to it. This mixture requires that the grass and weeds be dry. Wait for a sunny day with little wind, then spray the area where weeds are sprouting. 

Don’t water your lawn or carry out any other lawn care for the next 25 hours. Weeds will become easier to pull out my hands after being killed by the dishwashing soap mixture. You can repeat this procedure the next week if needed. 


– Does Body Soap Kill Grass?

No, body soaps will not kill your grass, even though they are not healthy. These soaps are made from mild and beneficial ingredients because they are meant to be used on human skin. That is why your grass will tolerate being exposed to them.

– Will Dish Soap Kill Moss?

Yes, dish soap will kill moss and is usually the preferred method. The best time is when moss is actively growing during early to late summer. Some moss grows between late summer till the start of fall.

Tale a plastic spray bottle and fill it with a mixture made from two ounces of dish soap in one gallon of water. Spray generously on moss patches every day. 

You will notice that soon whole patches of moss will begin to yellow and die. Rake them up, collect them and throw them according to the proper rules of organic waste disposal.


You have finally made it to the end of this article, where we have a small recap to sum everything up.

  • Dish soap will kill the grass by removing its outer layer and causing desiccation.
  • You must always dilute soap by as much as one tablespoon per gallon of water in order to be on the safe side.
  • You can mix water, vinegar, and soap to make a DIY solution to get rid of weeds and fungi.
  • Instead of dish soap, we suggest you use organic pesticides or anti-insecticides soap.

As you’ve completed reading this article, we hope you are now a better judge about how and when to use dish soap to take care of your lawn grass. Don’t forget to exercise caution when applying chemicals to any grass.

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