The internet is loaded with “life hacks”—tricks that you can use for tough jobs to save you time and money. Commercial lawn products can be expensive, so people have tried various household cleaning products to destroy moss on patios, driveways, and lawns. Two of the most popular ones include using regular bleach and vinegar to eliminate moss. But do these methods work? And which one is better? We will lay the information out so that you can decide.
Bleach vs Vinegar for Killing Moss—Which is Better?
Before we examine whether it is better to use bleach or vinegar to kill moss on your driveway or lawn, we need to understand some chemistry. The term “pH” is a measure of how acidic or basic (“alkaline”) a substance is. The baseline pH of water, for example, is 7. Anything higher or lower than that is considered basic or acidic.
Here are a few common examples of other cleaning agents with their pH levels:
- Lemon juice: 2–3
- Solid hand soap: 8
- Baking soda: 8
- Pine-Sol: 4
- Dishwashing soap: 8–10
So, what does this have to do with cleaning moss? Different plant species grow better in environments with different acidity levels. Grass likes a similar pH that humans do: around 6.5–7.0. This is why you can, in theory, drink from the same hose that you use to water your lawn.
But the moss you see in your bricks is different. Moss usually appears on your lawn, patio, or driveway in environments that are too acidic for grass to grow. Its ideal pH is 3.0–4.5—in the same range as lemon juice and Pine-Sol. This is why lime, a form of calcium carbonate designed for use in soil, works: it brings that soil pH closer to 7, the ideal level for grass and people.
When we talk about using bleach and vinegar to kill moss, we are using chemicals to make the environment either too alkaline or too acidic for it to grow in. This chemical difference affects how the moss responds to your treatment. So, which moss-killer works better, and why?
Which is Better?
The answer to “is bleach or vinegar better at getting rid of moss?” is something of a toss-up. They both take roughly the same amount of time to work. They both attack moss on different chemical levels. But as they say, the devil is in the details, and those details might decide which one is better for you.
The numbers don’t lie: when it comes to making a hostile environment for moss, basic bleach is better on pavement and bricks. The alkali/basic route with bleach is more effective because it makes the environment more hostile to moss.
Even if it’s diluted with water, the pH difference is substantial enough to wreck any moss you have.
Bonus: if any of the bleach is left behind, it may prevent moss from growing there in the future. (Please use lime for preventative measures.) Bleach-treated spots might not get moss for up to a year. Bleach removes moss and keeps it away.
If you are concerned about your bricks or lawn losing color, however, either dilute your bleach formula or use vinegar instead. Vinegar is also faster. It also causes less harm to the environment and is easier to make whenever you need it. Just bear in mind that it is not a long-term solution to any problems with moss.
If you need a short-term solution, such as an emergency patio party, or if you’re concerned about parts of your yard losing color, vinegar is superior to bleach. But because moss likes acidic environments, and vinegar doesn’t stick around, this relative peace will not last long.
Bleach is the stronger solution and needs to be handled with care because of it. It may also damage any plants around it. If you need to eliminate moss from your pavement or bricks, and do not care about any color loss, bleach is a good solution. However, because bleach is so strong, you need to dilute it to prevent it from causing damage.
Vinegar looks like it acts faster than bleach, but it needs to stay in an area for 24 hours before everything is dead. It is also the better option if you wish to plant anything else in the area. Finally, if you just have a little bit of moss, it’s easier to do the math for a 2:1 water-vinegar solution and put it in a spray bottle.
Whatever you do to eliminate moss from your property, please do not mix vinegar and bleach. If you have ever mixed baking soda and vinegar, you know that you can make quite a mess with chemistry, and this particular mess is dangerous. Mixing vinegar and bleach creates toxic chlorine gas. Please handle any chemicals carefully.
There are a few other cleaners (like dish soap and salt solutions) that can also banish moss, but we limited this article to 2. We hope we have given you some ideas to clean up before that last patio party of the summer!
How to Use Bleach to Kill Moss
Straight bleach will eliminate moss hard and fast. It works because bleach has a very high pH. The pH of commercial bleach is anywhere from 11–13. This is higher than the alkalinity of hand soap and baking soda. Using bleach makes the environment too alkaline for moss, and most other things, to thrive.
It does not stop there. Bleach is designed to kill bacteria and other antigens as well. Bleach is not environmentally friendly by any means. Please do not use bleach on areas where you intend to grow plants. If you do not want plants in the area, you can use bleach.
Bleach is also so strong that it may discolor anything else it touches. If you do not wish to risk this, bleach diluting your bleach solution with water is a good idea. Mixing 20 ounces of bleach into a 5-gallon bucket of water should be sufficient. Use a garden sprayer or backpack to spread it across the pavement or bricks. Rinse after 15–20 minutes. The moss should be dead within 24 hours. Rake and dispose of whatever remains.
How to Use Vinegar to Kill Moss
Along with being a cleaner and pesticide, you may have read that you can use vinegar to kill the moss on your lawn. The chemical that kills moss in vinegar is called “acetic acid.” This is the colorless, pungent chemical that gives vinegar its distinctive smell. It is a weak acid (pH 1.0) but still too acidic for the moss’s comfort.
The easiest way is to dump full-strength vinegar on the moss. No measurement is required. The moss likes acid, but not that much acid. However, many sites recommend diluting your vinegar. Start with a solution of 1 part vinegar to 2 parts water and adjust accordingly. This is easy to fit into a spray bottle that you might have in your house already.
Regular house vinegar may be effective on new moss. Other sites recommend various vinegar-to-water ratios, but even the vinegar you use on your salad can be effective on newly-grown moss. Otherwise, white or apple vinegar is your best bet for older, tougher patches of moss.
How Long Does It Take for Vinegar to Kill Moss?
This is a very good question. There is a lot of conflicting information on how long it takes vinegar to kill moss. Both vinegar and bleach take approximately 24 hours to be fully effective. However, because the moss starts dying after 5–10 minutes, many people assume this is all it takes to kill moss. It needs to stay on longer than that to be effective.