7 Best Organic Insecticidal Soap 2021 [Reviews & Guide]

Who doesn’t like the organic method to get rid of insects? And there are tons of organic products or recipes available for the plant. Insecticidal soap is one of them. Yes! You can use insecticidal soap or any natural soap to remove the insect permanently from your garden.

But not all the soaps are free from harsh chemicals. Remember; just saying organic soap doesn’t mean organic. It will be organic if the active ingredients and other containing substances are organic.

So, How would you know what is the best organic insecticidal soap? You have to buy different so-called insecticidal soap and do some experiments on your plant to get the best soap.

It sounds simple. But it isn’t.

That’s why I have researched and listed the 7 best insecticidal soap for your plant. In this article, I have explained why these soaps are best and how can you apply the soap to your plant.

What's On the Page

In a hurry? Here is the overall best insecticidal soap that you can buy right now for your plants-

Best Insecticidal Soap Spray for Plants- Comparisons

Insect Killing SoapVolumePrice
Safer Brand 5118 Insect Killing Soap(Best overall)16 oz
Bonide Insecticidal Soap Concentrate32 oz
Garden Safe Brand Insecticidal Soap24 oz
Natria 706230A Insecticidal Soap (Best Value)24 oz
Espoma Organic Earth-Tone Insecticidal Soap24 oz
Natural Guard Spinosad Soap16 oz
Miracle-Gro Nature’s Care Insecticidal Soap24 oz

What is insecticidal soap and How It works?

Insecticidal soap is the potassium-based long-chain fatty acid that can kill the soft-bodied insect. The main ingredient of soap is Potassium laurate. Insecticidal soap is also known as horticultural soap. It can be used as a spray or soil drench in any stage of plants including the flowering stage.

The long-chain fatty acid extract from coconut, plum, lavender, and other plant oil. Short-chain fatty acids can also be used in making insecticidal soap. But it may cause phytotoxicity.

How does insecticidal soap work?

Insecticidal soap works in many ways. The main mechanism is that it can disrupt the insect cuticle when it contacts the insect body. As a result, Dehydration occurred by evaporation and the insect dies.

Another possible mechanism is-

When the liquid soap comes in contact with the insect trachea, it blocks or disrupts the trachea. That’s why insects can’t open trachea and die.

Best Insecticidal Soap Spray -Reviews

1.Safer Brand 5118 Insect Killing Soap- Best for Flower(Roses, Knockout Roses)

Safer Brand 5118 Insect Killing Soap
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Safer Brand 5118 insect killing soap (16-ounce concentrate) is mostly used to kill spider mites, aphids, fuller rose beetles, thrips on roses, knockout roses, or other flowering plants.

Besides, it is also widely used to kill other insects (see the affected insect list on amazon) on trees, shrubs, fruits, vegetables. ornamental foliage and houseplants like the fern, rubber, aloe vera, pothos, bamboo, broccoli, cabbage, and onions without harming your family and pets.

This is a long-standing and powerful insecticide that is derivated from natural ingredients. It contains 50% potassium salt fatty acid and seaweed extract that can weaken the insect’s waxy coat of the cell membrane quickly.

Many indoor gardeners don’t like to use insecticidal soap for its soapy smell. Good news; It hasn’t any kind of harsh smell of soap and also dries quickly.

It is also approved as an organic insecticide by OMRI (Organic Materials Review Institute) and NOP(National Organic Program).

Though the manufacturer claims it doesn’t kill the beneficial insect. But as far I know, insecticidal soap is a non-selective insecticide. In my opinion, apply when you won’t notice honey bees or other beneficial insect activities.

How to use Safer Brand insecticidal soap?

Mix 4 tbsp of concentrate into a gallon of water and spray on your plant. Wait 7-10 days to reapply if needed. Don’t store the solution for future uses.

This insect-killing soap concentration can be stored four years unopened and one year once opened. You should try this trusted and proven remedy to kill the harmful insects of your garden. You may also choose the Ready to Use version of this insecticidal soap that has 2.0% potassium salt of fatty acid

 

2.Bonide Insecticidal Soap Concentrate- Best for Citrus Plant

bonide insecticidal soap
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Bonide insecticidal soap concentrate can be used in houseplants, vegetables, flowers, fruits greenhouses, ornamental, nut Trees, citrus(lemon, pomelo, orange, citron), berries, and Shrubs. It is a NOP-listed organic product for organic gardeners that is completely safe for all plants except sweet peas, nasturtiums, delicate ferns.

This the most powerful insecticide that can help you to get rid of insects like scales, plant bugs, sawfly larvae, psyllids, tent caterpillars, thrips, ants, spider mites, adelgids (woolly aphids), aphids, lace bugs, mealybugs, mites, grasshoppers, leafhoppers, earwigs and whitefly. It is also effective to eradicate insects at any stage ( adult, larval, Nymph, and pupal stages of some pests).

It has 47% potassium salt fatty acids as the active ingredient and has no flammable substances that make it suitable for the greenhouse plant but has a very little smell that is not noticeable.

You can use this insecticide before the day of harvesting. You don’t have to worry about the poisons. And using the Bonide insecticidal soap is completely healthy and environment-friendly.

How to apply Bonide insecticidal soap?

Mix 4 teaspoons of soap in 1 quart of water. Pour the mixer into a spray bottle and spray plant parts. Repeat the process weekly or bi-weekly to get an insect-free garden.

 

3.Garden Safe Brand Insecticidal Soap(24 oz) –Best Insect Killer for Houseplants

Garden Safe Brand Insecticidal Soap Insect Killer
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Garden safe is another trusted brand for organic products. They provide OMRI-certified insecticidal soap since 2002.

The perfect concentration, not having the soapy smell and quick-drying quality make it the most used and recommended insecticidal soap for houseplants. Also, the active ingredients of Garden safe insecticidal soap made from plant derivated fatty acids.

Moreover, It also can be applied in different outdoor plants and greenhouses to kill different garden insects successfully. Especially, it is a very effective soap solution to get rid of aphids, mealybugs. It can also kill insects at different stages.

Want to know how to use Garden Safe insecticidal soap?

You don’t need to add water to make the final solution. It is ready to use spray and contains 1% active ingredients. Just shake well and spray on the affected plant. To get a quick and effective result, you can also spray the soap on the backside of leaves and soil.

 

4.Natria 706230A – Best for Nightshade plant (Tomatoes)

Natria 706230A Insecticidal Soap
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Natria 706230A soap is another ready to use insecticide that has 1% potassium salts of fatty acids. It is the best for kill aphids, mealybugs, spider mites, whiteflies, and other listed pests in a minute. It is a multipurpose insect killer that can kill listed insects in different stages on vegetables, houseplants, greenhouse plants, ornamentals, fruit, seed, and nut trees.

Big news:

This non-synthetic soap works very fast and very gentle to the plants. It also acts as a preventive bio fungicide so that it can prevent many important diseases caused by the fungus. Moreover, It has no smell and perfect for your houseplant.

It is also ready to use insecticide that contains 1% active ingredient of potassium fatty acids. I like to use Natria soap on tomato plants to remove bugs. In my opinion, it is best of the best natural insecticide for tomato plants.

How to use Natria insecticidal soap?

Shake the container before spray and apply it directly to the plant. For better and effective results, apply the back of the leaves.

 

5.Espoma Organic Earth-Tone Insecticidal Soap- Best for Spider Mites and Thrips

Espoma Organic Earth-Tone Insecticidal Soap - 24 oz Spray IS24
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Espoma is another OMRI-listed brand that produces good quality organic products for the plant. The soap-based insecticide is one of the hot cake product of them. This 24 oz Espoma soap contains 1% of long-chain plant potassium fatty acid. It has zero percent of animal fat and short-chain fatty acid. That’s why it is safer for leafy vegetables and bedding plants.

Besides, It also kills the different insects (e.g aphids, mites, lace bugs, grasshoppers, scale insects, earwigs whitefly, slugs, caterpillars, etc) of trees, vegetables, fruits, citrus, and ornamental plants. Moreover, Espoma is also suitable for indoor plants and greenhouse because of not having any harsh smell.

I applied on my basil plant to get rid of white spots that cause of insects. I could work without any harm. No need to add water before spray. Just shake and spray on the plant.

 

6.Natural Guard Spinosad Soap- Best Spinosad Insect Control Spray

Natural Guard Spinosad Soap
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Spinosad is a natural compound made by the bacterial species Saccharopolyspora Spinosa that is highly toxic to insects. Natural Guard Spinosad Soap contains 0.940% of potassium slat fatty acid and 0.005% of spinosad.

It can be used to control aphids adelgids, ants, armyworms, beetles, borers, caterpillars, tent caterpillars, chinch bugs, codling moth, earwigs, fruit flies, gypsy moth, lace bugs, leafhoppers, leafminers, leafrollers, loopers, mealybugs, mites, mole crickets, plant bugs, psyllids, sawfly larvae, scale insects, spider mites, thrips, webworms, weevils, and whiteflies.

In my opinion, Natural Guard Spinosad Soap is good at kill aphids, whiteflies, and spider mites, and other soft-bodied insects.

The special benefit of this soap-

It can be used to kill insects from the lawn and also can control powdery mildew. To control this disease, apply on the infected areas when the first sign appears. It is ready to use insecticide. Just shake and spray to kill the listed insecticides.

 

7.Miracle-Gro Nature’s Care Insecticidal Soap – Best for Caterpillar Insets

Miracle-Gro 0747210 RTU24 Nature's Care Insecticidal Soap 24oz
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Last but not the least, the insecticidal soap of my list is Miracle-Gro 0747210 RTU24. It is another best fatty acid insecticide that has 1% potassium fatty acid as an active ingredient. Any soft-bodied insects will die within a minute if contact with the soapy water.

Is the bug damaging your tomato plants? or Is gnat kill your indoor plants? This OMRI-listed organic insecticidal soap may be the best solution for you. Moreover, it can kill other listed insects very quickly.

How to use Miracle-Gro insecticidal soap?

Simply, shake the bottle and spray it on the whole plant. Repeat the process after 7 days if you notice insects on the plants.

 

#Bonus: Best Soap for Making Insecticide at Home

Best soap for homemade insecticide

The homeowner always likes to use their kitchen products to use in their gardens. This is why I want to recommend a few general natural soaps for homemade insecticide. Concentration is the main problem of the homemade insecticidal soap. But you can fix the concentration by applying first on a small plant part.

Here is the recommended Soap for homemade insecticidal Spray. You can pick any of these-

  1. Bronner’s – Pure-Castile Liquid Soap(Best non-detergent soap)
  2. Earth Friendly Products ECOS Dishmate Dishwashing Liquid
  3. Murphy’s Oil Soap
  4. Marseille Soap Marius Fabre
  5. Ivory Dishwashing Liquid Soap

DIY insecticidal soap spray recipe for plants bugs-

  1. Pour 1 gallon of water in a sprayer and add  5 tablespoons of Castile soap/other recommended soap.
  2. A few minutes later, Add a teaspoon of vegetable oil/neem oil to prevent the solution from foaming too much.
  3. Let the soap dissolved and apply to the plants to get rid of insects.

To get more insecticidal soap recipe(dawn dish soap and murphy’s oil soap recipe), see my article about how to make insecticidal soap spray at home and make your own insecticidal spray.

How to Choose The Best Insecticidal Soap for the Plant?

Insecticidal soap is the most popular insect repellent among organic garden. It is a very eco-friendly and effective product. I have already mentioned 5 insecticidal soap for you. You may purchase any of these. But you have to consider some facts if you want to buy insecticidal soap from a horticultural soap.

Certified or Non-certified

You must consider that the insecticidal soap is certified by OMRI(Organic Materials Review Institute) or NOP(National Organic Program). OMRI and NOP are non-profitable organic product review organizations. They determine and certify whether the product is organic.

Harsh Substance or Chemical

Insecticidal soap is a biodegradable natural product. It should not contain any harsh chemicals that can harm the plant. So before choosing the insecticidal soap, you have to consider what substance it contains.

Affected Insects

Different brand soap can affect different insects. The brand provides a list of the affected insects. If you need an insecticidal soap to get rid of specific insects, you need to check whether the name of the insect remains in the list or not.

The Concentration of the Soap

Some brand provides high concentration soap. You need to mix water before using it. For example-Safer brand insecticidal soap.

On the other hand, some brand provides readily useable low concentred soap. You don’t need to water before using them. For example- Natria insecticidal soap.

Soapy Smell

Some people ignore insecticidal soap for its bad smell. But all the insecticidal soap doesn’t have a bad smell like soap. You have to consider this feature before purchasing it. This feature is most considerable for you if you want to buy an insecticidal soap for indoor plants or a greenhouse.

Not Harmful for the Pets

Many gardeners forget to consider this important thing before buying or applying any insecticide or fertilizer. Some substances can harm your pets. So you have to make sure that the insecticidal soap won’t harm your pests.

Some Others Popular Brands of insecticidal Soap

I have already mentioned 7 best brands of insecticidal soap. Besides these, some other brands are also popular among gardeners. For your convenience, I have mentioned the name too-

  1. Kopa insecticidal soap
  2. Schultz insecticidal soap
  3. Ortho insecticidal soap
  4. Green Earth insecticidal soap
  5. Rose Pharm organic insecticidal soap plus Miticide and Fungicide

How to Use Insecticidal Soap on Plants?

Step 1: Shake Well

Shake the solution before spray. It helps to dissolve and disperse the soap throughout the water.

Step 2: Test on the Small Portion of the Plant

You may know insecticidal soap can burn the plant leaves. This may happen for high concentration, high temperature, or sensitivity of the plant.

So you have to apply on the small portion of the plant and wait 24 hours. If the plant shows any unnatural wilting sign, wash the plant with water immediately. Dilute the concentration and reapply for the test. If the test is positive, go to the next step.

Step 3: Water the Plant

Thoroughly water the plant before applying the soap spray. Stressed and wilted plants react negatively to the soap. Moreover, it is a contact insecticide. If the plant wet, the more insect will come in contact with this insecticide.

Remember, soapy water doesn’t work, if it dries once. So watering can help to prevent drying quickly.

Step 4: Spray the Solution

Now spray the solution on the plant foliage. Don’t ignore the bottoms of the leaves. Most of the gardening insects(whiteflies, slugs, mites, hoppers, etc) hang on the underside of the leaves. So to get a better result, you must spray the solution thoroughly top to bottom of the leaves.

Step 5: Reapply the Solution

If you notice any sign of insect movement, repeat the treatment after 7-10 days. In an epidemic condition, you may repeat the treatment after 2 or 3 days until the insects disappear.

Precautions and Tips

  1. Do not use the on plants sensitive to Insecticidal Soap.(sweet peas, jade plant, lantana, nasturtiums or delicate ferns. Bleeding heart, horse chestnut, Japanese maple, mountain ash are most sensitive to soap)
  2. Some varieties of different family plants like azaleas, begonias, camellias, fuchsias, gardenias, orchids, and impatiens have shown sensitivity. If wilting occurs after a few hours of application, spray water and rinse the plant. Here are some slightly sensitive plants- (Cherry, Conifers, Crown of thorns, Easter lily, Gardenia, Hawthorn, Lantana, Maidenhair fern, Nasturtium, Plum, Purslane and some varieties of tomato)
  3. It is a contact insecticide, so apply such a way that the insect comes in contact with the insecticide.
  4. Shake the solution well before spray.
  5. Don’t apply during the full sun.
  6. It causes temporary eye injury and skin irritation. So wear protective goggles and an apron.
  7. If the soap gets in your eye, hold your eyes open and rinse gently with clean water for a few minutes.
  8. Spray the insecticide in the evening when the beneficial insect(bee) activity is low.
  9. Is it kill moths, worms and May I apply on rubber plant or bonsai? People are always asked this type of question. Honestly speaking, the manufacturer can’t answer the question confidently if the plants and insects do not remain on their list. That’s mean it doesn’t work on those insects.
  10. Don’t use just the upper leaves.apply also undersides of the leaves.
  11. Repeat the treatment weekly or bi-weekly, If needed.
  12. Insecticidal soap also can be used as a preventive fungicide to control fungal diseases like powdery mildew of tomatoes.
  13. Some insecticidal soap may use on the lawn to kill algae and mosses.

Warnings: Do some experiments. Soapy water with too much concentration can burn and kill your plants. Apply the solution on the small part of the plant and wait 2-3 days. If everything okay, spray on the entire plant. If you notice any burn sign, mix more water, and dilute the solution.

Frequently Asked Questions

#What is the Best Time to Apply Insecticidal Soap?

As I already told, Insects will come to contact with the insecticidal soap to kill them.

You have to spray when the temperature is cool and the weather is calm as if there was no angry sun over the plant. So, the plant stays wet for a longer period of time. Considering this fact, early morning or the evening( before 6 am or after 5 pm) is the best time to apply insecticidal soap.

Moreover, You may apply directly to the insect when you will notice the insect activity increases on the plant.

#How often Can You Spray Insecticidal Soap?

Insecticidal soap can kill the insect when it contacts the insect. So you have to repeat the application process. You can repeat the process after 1 weak if you appear any sign of insect infestation.

#Is Insecticidal Soap Safe and Organic?

The quick answer- Yes! it is organic and safe if you apply the solution with proper concentration. But the answer doesn’t end here. Many homeowners or gardeners ask- is it safe for pets, human, honey bees? or is it safe for a succulent?

Insecticidal soap doesn’t harm humans and pets. It is not toxic insecticide to humans and other mammals. But it may cause temporary skin irritation.

Though many gardeners claim that the insect killer soap doesn’t harm honey bees, but this is not authentic information. So apply insecticidal soap when the honey bee is less active (early morning and the evening).

Some varieties of succulents can burn. Don’t apply soap spray without testing.

#Does Insecticidal Soap Kill Spider Mites?

Insecticidal soap can kill any soft-bodied insect. Every brand provides a list of affected insects. Here I will tell you name of some common soft-bodied insects these are affected-

Spider mites, Whiteflies, Thrips, Caterpillars, Mealybugs, Jumping insects, Earwigs, Aphids, Beetles, Sawflies, Fungus Gnats, Ants, Squash Bugs, Box Elder Bugs, etc.

The quick tips- Observe the insect. If it has a soft body, then definitely the spray will work.

#How to Store Insecticidal Soap?

Store the insecticidal soap concentration in a cool, dry, well-ventilated area and away from heat sources (temperature<100 degrees) and direct sunlight. Unopened soap can be stored for more than 4 years and an opened soap concentration can last more than a year.

Make as much the solution as you need for a few days. The prepared solution can be stored only a few days. If you don’t need the solution for a week, dilute the solution with water and store it in cool & dry weather.

#Insecticidal Soap with Pyrethrin or Neem oil

It is safe to add neem oil or pyrethrin into the insecticidal soap. Pyrethrin and Neem oil also act as insecticide individually. So gardeners add these into soap spray to enhance the activity.

The safer brand provides insecticidal soap with pyrethrin that you can pick- Safer Brand Insecticidal Soap & Pyrethrin Concentrate.

#Insecticidal Soap vs Neem Oil

Insecticidal soap and neem oil can suffocate and kill if the insects come in contact. Both can kill some common soft-bodied insects. Moreover, soap can kill some insects that neem oil can’t and neem oil can kill some insects

these are not affected by the insecticidal soap.

Both are organic and safe if the concentration is perfect. So, the best idea is to mix neem oil and insecticidal soap. But don’t apply it to the plant without experiment. Dilute the solution if the plant burn.

Here is the recommended best quality neem oil- Bonide (BND022) – Ready to Use Neem Oil

#Is Dawn An Insecticidal Soap?

Dawn is dishwashing soap. It is best for cutting and fighting grease. Dawn detergent also contains potassium-based fatty acids that kill insects like commercial insecticidal soap. Dawn dish soap is a completely safe pesticide for plants if the concentration is perfect.

Mix 2 tablespoons of dawn detergent and 2 tablespoons of vegetable oil with 1 gallon of water to make dawn insecticidal soap.

#Does Soap Kill Grass?

Soap doesn’t kill or harm grass. But if the soap contains any harmful or aggressive substance, the lawn will damage. Read the label of insecticidal soap before spraying on the lawn. All the brands provide proper instruction that their insecticidal soap will be safe for grass or not.

A homemade dish safe may also be safe for grass. But the concentration has to less than the other plants.

#Will Dish Soap Kill Plants?

No matter the insecticidal soap is commercial or homemade, It is always less toxic for plants and humans. Dish soap doesn’t kill plants if you know how to use and what amount to use. If you notice any burn or killing sign after applying dish soap, wash the plant with water. Dilute the dish solution and reapply to the plant after a few days.

#Is Dawn an Insecticidal Soap?

Dawn liquid dish soap contains nearly 2% of commercial insecticidal soap. And that portion can help you to kill insects like insecticidal soap. So, you may be called Dawn is insecticidal soap.

#Where to Buy Insecticidal Soap?

I have mentioned 5 insecticidal soaps that best-selling products under the organic insecticide category on amazon. You can purchase any of these from my list.

Moreover, You can buy from near horticulture store or insecticidal store. But before buy from there, you must consider a few things to pick the best one.

Conclusion

Nowadays, insecticidal soap is the gardener’s first choice to protect the plants from insects and it has been doing its job successfully. Besides killing insects, it also can prevent some fungal disease development. So, take the best insecticidal soap for your garden and protect your plant from garden insects.

Lastly, I want to tell you, never apply any insecticidal soap spray without testing in the small part of your plant. Because some of the plants are so sensitive. It is not a wise idea to kill the plant instead of killing the insecticide. Also, read carefully the label of insecticide to learn the dosages of specific plants.

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