Roses are a type of flower that is very popular among Vietnamese people; they are often used for various purposes and can be found everywhere. However, during the growing process, farmers are highly susceptible to aphid infestations, which can damage the flowers and reduce crop yields. Therefore, farmers need to find a way to control this insect without harming the surrounding environment, and treating rose aphids with dish soap is the best solution.

What is the overview of rose thrips?

Thrips, also known as “bù lạch,” belong to the order Thysanoptera and the family Thripidae. They are insects that feed exclusively on plant sap, which has a negative impact on trees and crops. Among them, roses are one of the plant species most frequently attacked by thrips.

Rose thrips typically appear in the spring and summer, when the weather is hot and sunny. If rose gardens are planted too densely and debris from old plants is not thoroughly removed, thrips will spread extremely quickly.

Some signs to identify rose thrips

Thrips are extremely small insects, making them very difficult for humans to spot with the naked eye. Therefore, as roses grow, farmers must observe them carefully and thoroughly to detect them. Here are some signs that can help farmers identify aphids on roses more easily:

• Thrips typically attack the following plant parts: young leaves, young buds, newly opened flowers, and mature leaves.
• These bugs feed on or damage the underside of the leaves, causing them to curl.
• The buds will bloom slowly or may not bloom at all, and if they do bloom, the petals will be misshapen, unevenly rounded, and less vibrant in color than usual.
• On mature leaves, mottled, dark brown patches appear.

The Damage Caused by Aphids to Roses

Aphids are insects that feed on plant sap, which is why they cause a great deal of damage to roses, including:

• Thrips often attack flower buds, causing them to shrivel, fail to bloom, and wither quickly.
• In mature flowers, the color fades, they are smaller, and they wilt quickly.
• This limits the plant's ability to photosynthesize, causing it to grow unevenly and not reach its normal size.
• It weakens the rose's resistance, making it more susceptible to common diseases and causing it to lose its vitality.
• When aphids suck sap from roses, they leave scratches, creating conditions for harmful fungi to thrive and infect the flowers.
• Thrips won’t kill roses immediately, but they will cause them to wither gradually, preventing them from growing and developing normally.

Explaining Why Dish Soap Can Be Used to Treat Rose Aphids

Rose thrips can be harmful, but there are also many ways to treat them without resorting to pesticides. Among these methods, treating rose thrips with dish soap is widely used by many gardeners. Why does this method work? There are two main reasons:

• Dishwashing liquid Because it is a liquid, when sprayed on roses, it easily adheres to the branches, stems, and leaves. This blocks the aphids’ breathing holes, preventing them from moving; they will eventually die.
• On the other hand, dish soap also has very strong antibacterial properties, which quickly kill thrips. In addition, their eggs will not hatch after coming into contact with the dish soap solution.

For these reasons, farmers have adopted this method to control thrips, which both minimizes the impact on the surrounding environment and saves money.

How to Properly Treat Rose Aphids with Dish Soap

There are many ways to get rid of thrips, and using dish soap is one of them. To ensure maximum effectiveness in eliminating thrips, I’ll walk you through the process in detail. How to Treat Aphids with Dish Soap Follow these three steps to care for your roses:

Step 1. Prepare the dishwashing liquid solution

Before mixing the dish soap solution, you should use a strong stream of water from the hose to rinse the leaves, stems, and pot surfaces of the roses thoroughly. The purpose of this is to dislodge some of the aphids from the plant. In addition, removing the layer of dust and dirt clinging to the plant helps the dish soap adhere more effectively to the rose bush.

Mix 12 ml of dish soap (Okula, etc.) into 1 liter of clean water, then add 1 drop of cooking oil. Next, shake the mixture vigorously to ensure that the cooking oil, dish soap, and clean water mix together as thoroughly as possible.

Step 2. Start spraying dishwashing liquid onto the roses

Because dish soap has antibacterial properties and tends to cling to surfaces, you should only use the diluted mixture described in the previous step when the sun isn’t too strong—ideally, spray it between 6:00 and 7:00 p.m. When spraying, keep the following in mind:

Spray from the outside toward the inside of the plant, from the top of the plant down to the bottom of the pot, and from the upper to the underside of the leaves. In general, be sure to spray all areas where thrips commonly hide (the undersides of leaves, leaf axils, flower buds, etc.).

Step 3. Wash the roses thoroughly and rinse them under running water.

After spraying the mixture between 6:00 p.m. and 7:00 p.m. today, wait until the next morning (about 10 hours later) before the sun comes up (around 7:00 a.m.). Use a garden hose to spray the entire plant vigorously to wash away the dish soap. This step serves two purposes: First, to remove the thrips that were previously killed, and second, to thoroughly clean off any remaining dish soap.

This step is extremely important; if you leave the roses in direct, intense sunlight, combined with dish soap, the leaves will be very prone to scorching—causing them to turn yellow. 

Tips for Treating Rose Aphids with Dish Soap

Although these tips may seem minor, they are a very important part of the process if you plan to use dish soap to treat aphids on roses:

• Dishwashing liquid is not a specialized treatment for thrips. Therefore, its success rate and effectiveness will not be as high as those of specialized thrips treatments.
• Using dish soap on roses that are just beginning to show signs of thrips (mild to moderate infestation) is more effective than treating plants with severe infestations.
• Be sure to rinse the plant thoroughly after spraying dish soap on the roses; if the sun is very strong, the dish soap can cause the roses’ leaves to turn yellow and scorch.
• If the aphids are still present after using dish soap a second time, you should try other methods to eliminate them.

The article above Okula Vietnam We’ve shared with you how to treat aphids on roses using dish soap—a chemical-free way to eliminate aphids—along with some precautions to keep in mind when using this method. We hope this information will be helpful to you.