As a gardener, you may be looking for several ways to improve your tomato plants look fresh and find a natural way to nourish them. Using vinegar is one of the methods to get rid of the pests on your plant. But, is it effective to use vinegar to kill tomato plants? Here are some statistical data that you may want to know before using vinegar.
According to the National Pesticide Information Center, home vinegar which is 5% concentrated isn’t an effective herbicide and will not kill tomato plants. However, vinegar can be used as a pesticide if diluted and used properly.
Like Spirit vinegar, 20% or more concentration is capable of killing tomato plants for its herbicide properties and use for weed control. So, it depends on what concentration and purpose of use of the vinegar for your tomato plans.
What are the vinegar’s properties? Why or Why not Kill tomato plants?
Vinegar is acetic acid and it will act as a “burn” the plant when it’s in contact with the plant for a long period of time with a high concentration of use. The leaves will eventually turn brown and die if you don’t rinse them off.
However, home-use vinegar (CH3COOH) is around 5% concentration which can be diluted with water and used as a foliar spray for the tomato plants parts. As it shows the acidic nature, it can be used as a pesticide to some extent but not recommended to use undiluted vinegar or full strength.
In fact, The most common component of distilled vinegar is 5 to 8% of acetic acids, 92-95% of organic matter, and water. Spirit vinegar is a stronger variation of regular vinegar that has 5-20% acetic acid in it, which is harmful to plants in direct use.
* Vinegar can harm plants if not used carefully. It is important to know the concentration of the vinegar and read the instructions before using it on your tomato plants.

How does vinegar affect plants (Use and Misuse Of Vinegar.)
Fertilizer
Vinegar isn’t a fertilizer, but it can be used as a foliar feed to deliver nutrients to the plant’s leaves. Acetic acid has carbon and hydrogen which are collected naturally by the plants so, it won’t be needed as a fertilizer for the plants.
Pesticide
You need to use a very diluted solution of no more than 2-3 tablespoons of vinegar per gallon of water as too much vinegar will damage the leaves. Besides that, you need to be careful when using vinegar as a pesticide.
It will work as a natural herbicide by killing the plants that it touches. So, make sure to only spray the solution on the leaves of the plants that you want to get rid of and not on the plants that you want to keep.
Weedkiller
Vinegar can be used as a natural weedkiller. You can either use white vinegar or apple cider vinegar for this purpose. The best time to spray the solution on the weeds is on a sunny day when the temperature is above 80 degrees Fahrenheit. This will allow the solution to evaporate quickly and prevent it from harming your plants.
Keep rodents and other animals out of your garden
You can use vinegar to keep animals out of your garden. Simply mix equal parts of vinegar and water in a spray bottle and spray it around the perimeter of your garden. The strong smell of the vinegar will deter animals from entering the area.
Acidify your soil
Soil Ph is a measure of the acidity or alkalinity of the soil. The scale ranges from 0 to 14, with 7 being neutral, below 7 being acidic, and above 7 being alkaline.
You can use vinegar to lower the pH of your soil if it is too alkaline. Simply mix 1 part vinegar with 9 parts water and sprinkle it over the soil. You can also add vinegar to your compost pile to help lower the pH of the finished compost.
Benefits of vinegar on tomato plants
- Spraying diluted vinegar on plant leaves only increases their vitality but also improves crop quality.
- Spraying also helps to get rid of harmful insects and some plant diseases.
- Applying wood vinegar to the soil in high concentrations inhibits eelworms and soil diseases.
- In low concentrations, it breaks down in the soil and increases the number of useful microbes.
- Vinegar is effective against powdery mildew, gray mold, and black spot.
- It can also be used as a natural weed killer.
Is Vinegar a Good Bug Repellent?
Acetic acid is a good repellent for many soft-bodied pests such as aphids, mealybugs, and spider mites. The vinegar smell also can repel many animals including dogs, cats, and deer. Ants, mosquitoes, and, other environmental pests don’t like the smell of vinegar, so it can be used as a good repellent.
In order to create a bug repellent, you will need to follow these steps:
- First, choose the size of the plant.
- Second, use diluted vinegar (3-7%).
- Third, pick which day you want to start using the repellent.
Vinegar Measurements | Water Requirements | Soap (1 Tablespoon = 15 ml) | |
Small plant with short branches and leaves | 100 ml | 300 ml | 15 ml |
Small plant with short branches and leafs | 70 ml | 300 ml | 25 ml (To manage adverse effect) |
Indoor plants | 50 ml | 300 ml | 30 ml (Companion ) |
FAQ:
Can I use apple cider vinegar on a tomato plant?
Apple cider vinegar is not recommended for use on tomato plants because of the high risk it has of damaging the plant. The vinegar can burn the leaves and stems of the plant, and also disturb the pH balance of the soil. If you must use apple cider vinegar on your tomato plants, be sure to dilute it with water (1 part vinegar to 10 parts water) and only spray it on the leaves, avoiding contact with the stem and fruit.
Will vinegar hurt houseplants?
Yes, vinegar can hurt houseplants. Vinegar is an acidic substance, and when it comes into contact with plants, it can cause them to wilt, brown, or die. If you accidentally spill highly concentrated vinegar on your plants, flush the area with water immediately to dilute the acid.
How long does vinegar last in soil?
If you mix vinegar with water and apply it to your soil, the vinegar will only last for 24-48 hours before it is broken down by the soil bacteria. However, if you add vinegar to your compost pile, it will help to lower the pH of the finished compost.
Wrap-Up:
You can use vinegar for your plants in different ways. It can help to keep the animals away, lower the pH of your soil, and also be used as a bug repellent. But as a fungicide, pesticide, or herbicide, I would suggest not making vinegar a primary choice. There are more effective and safer products out there for those purposes.

I am a graduate of Bangladesh Agricultural University, where I delved into various agricultural disciplines, equipping me with a profound understanding of agriculture. Beyond academics, I have hands-on experience in gardening and crop cultivation. My passion is to embrace sustainable farming and horticulture. With a BSc in Agriculture, I am dedicated to promoting environmentally conscious and efficient agrarian practices.
Bachelor of Science (BSc) in Agriculture (Hons.)
Master of Science. (Sustainable Agriculture & Food Security ) (MS)
Bangladesh Agricultural University