Yes, You can. Spraying your tomato plants with a soapy water solution is an effective way to keep pests at bay. The soap acts as a barrier, deterring insects from landing on the plant and preventing them from feeding. It preventss. You can make your soapy water solution by mixing your home dish soap with water.
According to journal reports, horticultural oil, and insecticidal soap were both effective in killing calico scale insects (73% and 93%, respectively) and oleander scale insects (67% and 78%, respectively).
However, there are a lot of other advantages of using soapy water for your plants. It can also act as a fungicide and can help to control black spots on roses, powdery mildew, and rust. So, not only does it keep the pests away, but it can also help your plants stay healthy and disease-free.
Here, I will let you know of my own experience with tomato cultivation along with the soapy water solution.
Where to put soapy water on tomato plants?
As I know tomato plants are affected by a wide variety of bugs and insects. Their nature of damage and injury to the plant is different. Some insects affect the plant parts like leaves, flowers, and fruits while some insects are known to be vectors of plant diseases.
So, it’s very necessary to know about the pests before taking any step toward them. Let’s know some of the behaviors, nature of the damage, and specific portion infestation of the plants-
|Nature of Damage
|Affected Plant Parts
|Damaging the plants by feeding on their sap, stunted growth, distorted leaves, and yellow patches
|Tender shoots and lower leaf surfaces
|They feed on the young leaves and shoot sap of the plant
|Undersides of plant leaves
|Take the sap out of the xylem and phloem tissues of the plant
|Plant parts shoot, young growing apex
|Use their mouthparts to pierce plant cells and suck the ensuing juices
|The backsides of leaves
|Plants with white or brown spots on their leaves have had their cells damaged
|Throughout the plant but mostly underside of the leaves (vegetable)
What Types of soapy water should you use?
When it comes to spraying on your beloved tomato plants, there are two types of soapy water you can select for your plants-
Mild dish soap: You can use any kind of liquid dish soap that is available in your home. Just add one or two tablespoons of dish soap in one gallon of water and mix it properly then pour the solution into a spray bottle.
Insecticidal soap: This type of soapy water is specially designed for plants and gardens. It is available in most garden supply stores. These have special ingredients ( long chain ) in their chemical composition which perfectly work on tomato plants and get rid of insects and bugs easily.
|Mild dish soap
|A long chain of Potassium salts
|Long chain of Potassium salts
|of fatty acids
|of fatty acids
|Less effective for pests
|Highly effective for garden pests
|They are alkaline
|Safe for use
|Can be used on vegetables up to harvest
Would adding additional elements to the solution make it more effective?
If you use soapy water with some other extra elements like neem oil, garlic spray, turmeric powder, or hot pepper spray then it will be more effective in getting rid of pests from your tomato plants.
You can use any one of these ingredients or all of them together to make a solution that will work best for your plants.
My Experience: It was last summer, I had grown some tomatoes in my balcony garden and was regularly spraying soapy water on the plants, It’s effective.
But when I used some extra elements like garlic spray or neem oil onto it, The results were amazing as not only did the pests stay away but also the plant growth was boosted.
The tomatoes were healthy and juicy. I would recommend this solution to anyone looking for an effective way to keep their plants pests-free.
How to Use soapy water on tomato plants?
In this guide, I will show you exactly how to use soapy water with step-by-step instructions and accompanying notes.
#Step-1: First, Choose the right mild dish soap or insecticidal soap.
To get fruitful results, it’s very necessary to select the right type of soapy water. If you want to make a homemade solution, Then you must check its chemical composition whether is hurtful for the tomato plants or not. Most of the time dish soap isn’t toxic or harmful to plants, But still, you need to be sure about it.
If you are using an insecticidal soap, Then it will be more effective as these are designed especially for plants. So, you can get started with toxic-free mild soap water initially and then use it with efficient insecticidal soap water.
#Step-2: Second, mix the soap with water to create a lather.
For making a soapy water solution, You will need 2 or 3 tablespoons (20-40 ml) of soap and one gallon of water. Pour the water into a clean bucket then add the required amount of soap to it. Make the lather by stirring the water with a spoon or a brush.
#Step-3: Third, Add the solution into a spray bottle.
After you are done with making the lather, it’s time to add this solution to a spray bottle. You can use any empty plastic bottle or a garden sprayer for this purpose. You can use some extra ingredients into it like Peppermint or lavender scents to make it more effective.
#Step-4: Fourth, Spray the solution onto the tomato plants.
Now, Your soapy water solution is ready to use. You need to spray this solution all over your tomato plant, Focusing more on the underside of the leaves as most of the pests stay there. Also, don’t forget to spray the stems and branches. You can do this once or twice a week to keep the pests away from your plants.
How often should you use soapy water on your tomato plants?
Soapy water isn’t harmful or dangerous for tomato plants, so you can use it as often as you need to to keep pests away. Some gardeners like to make a mixture of one part soap to ten parts water and apply it every week or so, while others use it more frequently.
Ultimately, it’s up to you how often you want to use soapy water on your plants. Just be sure to get rid of the bugs from the plant until they’re no longer a problem.
Besides you can make a scheduled spraying routine apart from 3-5 days intervals to keep the tomato plants healthy which are as follows,
- When the plants are young: You should start spraying when the plants are about 6 weeks old.
- Before flowers bloom: Once the plants have started to bloom, you should spray them once a week.
- After flowers bloom: Once the flowers have begun to fade, you should reduce the spraying to once every two weeks.
Thus, to keep the tomato plants healthy, you should follow a spraying routine. In case of severe infestation, you must look for the symptoms and do the steps for that particular disease.
Will soapy water kill bugs?
Yes, Soapy water kills the bugs as it works by suffocating them. Once the bugs are covered in soap, they can no longer breathe and eventually die. Into their body structure, the soapy water inhibits the natural process and works as a barrier.
Do note that while soapy water is an effective way to get rid of bugs, it will only work if you spray the solution directly onto the pests.
If you’re dealing with a severe infestation, you might need to use other methods in addition to soapy water to get rid of all the bugs.
Will Soapy Water Hurt Ladybugs?
Gentle and nontoxic, soft soapy water will not hurt the ladybugs. But if you use more chemical compounds in it, then it might harm them. You can use a general dishwashing soap that is soft and has a neutral pH to make a solution for cleaning the ladybugs.
However, If you use insecticidal soap it won’t kill the beneficial and large types of bugs, only affects aphids, mealybugs, spider mites whiteflies, etc.
In the end, all the statistical data I got and according to their condition, it is not bad to use soapy water on them. Still, I would recommend you do a patch test before using any kind of soap or chemicals on your tomato plants and observe it for 24-72 hours whether there is any change or not.
Because some tomato plant species are very sensitive to chemicals. So, use the soapy water mixture and get rid of harmful aphids, whiteflies, thrips, and other pests from your tomato plants.
I hope this article was helpful and informative. If you have any questions or suggestions, feel free to leave a comment below.
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