Does Soapy Water Kill Caterpillars?

What makes caterpillars so harmful is that they have a huge appetite for a variety of different plants. You will find caterpillars eating on multiple plants, causing damage wherever they go. And that’s why you may want to kill them. Soapy water is a known, natural pest deterrent. But does soapy water kill caterpillars too?

Unfortunately, soapy water does not kill caterpillars. However, it does enough to repel them and keep them away from vulnerable plants.

Using soapy water to tackle different insects is a popular method used by gardeners. However, if you intend to use soapy water to kill caterpillars, it will not work.

The soapy water will only cause the leaves to become slippery and cause the caterpillars to slip. In some cases, the scent may be too strong for the caterpillar, which causes it to stay away from the plant. Therefore, it might be no good at killing them but can work well to deter them.

How Do You Use Soapy Water to Kill Caterpillars?

Even though soapy water cannot kill caterpillars, you can still use it to deter them, so they stay away. What is great about using soapy water is how easy it is to use. You can make soapy water in your home, using ingredients you’re going to have in the kitchen already.

After creating the soapy spray, you need to conduct a patch test to ensure that it does not cause damage to your plants. This will help you understand the amount you should be using and whether your plant will react adversely to the spray.

You need to spray a small amount to an area and wait for 24 hours to notice any visible differences in your plant. 

If you notice changes such as leaves changing colour, browning, or gaining spots, you should not use soapy water on your plants, obviously.

However, if there are no such changes in the plants, you can continue to use the mixture against caterpillars and protect your plants from extensive damage. 

Using soapy water in your garden against caterpillars will not lead to instant results. This method requires a regular process and consistency. You need to keep spraying the leaves and ensure they remain soapy so caterpillars do not come near them.

The caterpillars will likely come back to eat the leaves when you stop spraying the leaves. That’s why soapy water, no matter how effective, is not a long term solution to the problem.

What Kills Caterpillars Instantly?

If you have a large, uncontrollable caterpillar infestation, the best way to go about it is to remove the bulk of them by hand. If you spot a group of caterpillars feeding on a plant, you may remove that part of the plant and get rid of it.

Simply snip those individual leaves off the plant, roll them up and instantly dispose of them. While doing so, however, you must ensure that you do not let caterpillars fall on the ground. 

If you do not wish to remove the part of the plant, you can opt for removing the caterpillars manually by hand. You can put on gloves and remove the caterpillars, maintaining a tight grip on them, so they do not escape. 

In addition, you can also try using pheromone traps which can be found in most DIY stores and garden centres. This will keep the caterpillars away from the plants.

An anti-insect net is also useful in protecting plants, especially vegetable crops such as brassicas which do seem to take a lot of damage from caterpillars.

How Do You Make a Soap Spray for Caterpillars?

You only need to ensure that you use the right ratio in your soapy water recipe. The ratio you use should always be ten parts water to one part soap. After mixing the ingredients together, you can add it to an empty bottle and spray it on any caterpillars you may spot. 

While creating the spray, it is important to dilute the mixture. For the soapy mixture to work, it is important to dilute the soap in water as it gets activated by moisture. You must use liquid soap, of course, when making your soap spray for caterpillars.

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Caterpillars are an important part of the ecosystem; however, having too many of them can result in extensive plant damage. This is why gardeners look for ways to control the caterpillar population.

Many believe that soapy water can be used to kill caterpillars. However, soapy water will only cause the caterpillars to slide from plants or repel them through the strong smell. You can create your soapy water mixture by mixing one part of water and two parts of soap. 

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