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Boric Acid for Roaches: Does it kill?

There are plenty of methods to kill cockroaches, including a palmetto bug. These methods include chemical insecticide sprays, roach traps, gels, electronic roach killing devices, and natural remedies. Although these methods are very effective, the real dilemma is that roaches keep reappearing after some time.

Does boric acid kill roaches? Yes! Boric acid effectively kills roaches by interfering with neurotransmission, disrupting their digestive system, and crippling the locomotory system. Besides killing roaches, boric acid also destroys the roach’s egg.

The boric acid kills the palmetto bugs slowly, often taking about 2 to 3 days. The good thing about using boric acid is that it stays on the surfaces for long, effectively controlling palmetto bugs’ reemergence.

Before you read further, just a quick question. Tired of cockroaches and looking for a permanent solution?

Stop wasting your time, invest in these products and follow this guide: How to get rid of roaches? You will be roach-free in 10-20 days.

1. Max Force Glue Traps
2. Advion Gel Baits
3. Harris Powder Bait
4. Gentrol Insect Growth Regulator
5. Loctite Foam Sealent


Optional Items
1. Gel Bait Professional Gun
2. Torch
3. Powder Bait Puffer
4. Insecticide Spray to kill a reveled colony in a single shot

Boric Acid for Roaches

You may be wondering where to buy boric acid? But it’s quite easy to source it. You can easily purchase boric acid at a local pharmacy or online at Amazon. Below are the best listings on Amazon of boric acid for roaches.

  1. Roach Killer Boric Acid by HARRIS (No need to mix anything with it, ready to use for roaches)
  2. Boric Acid Powder by Greenway Biotech
  3. Humco Boric Acid Powder, 6 oz.
  4. Fine Powder Boric Acid by Duda Energy
  5. Boric Acid Pure Fine Granular Powder

How does boric acid kill roaches?

Boric acid is an odorless and colorless crystal or white powder with weak acidic properties. It is often used as an insecticide, antiseptic, and as flame retardant.

The insecticide properties have long been established; boric acid is often used for this purpose with excellent outcomes. The boric acid has also proven lethal for roaches, including palmetto bugs.

Once you sprinkle boric acid at different corners around the roach-infested area, all you have to do is to wait. The powder will most likely stick to the roaches’ wings, legs, bodies, and antennas.

The boric acid can get absorbed through the cockroach’s body or be accidentally ingested. It may also be ingested by the bug if the powder is mixed with sugar or starchy food.

Once the boric acid reaches inside the body, it kills palmetto bugs and roaches by following ways.

  1. The boric acid interferes with the palmetto bug’s neurotransmission, disturbing nerve conduction.
  2. It has the ability to dissolves the exoskeleton of the bug, this cripples the bug’s movement.
  3. The abrasive nature of boric acid puncture the palmetto bug’s digestive tract, rendering it non functional.
  4. Due to its acidic ph and osmotic property, the boric acid disturbs acid-base and fluid balance.

Boric acid works great for a wide variety of roaches including German cockroaches, American Cockroaches, and Baby palmetto bugs. Boric acid will also eliminate roach egg cases including palmetto bug egg cases.

How to use boric acid for roaches?

When I tried to use boric acid to kill palmetto bugs and other roaches, I was pretty upset with the poor results. I wondered why this method keeps on failing despite many articles stating its efficacy.

I tried to see the bug’s response to boric acid. After many failed attempts, I concluded that roaches, including palmetto bugs, were least interested in feeding on my magic powder. This is because it had no smell at all.

To my surprise, when I mixed it with the few items listed below, it worked wonders.

Can I mix boric acid with water and spray it? Boric acid is sparingly soluble in water at room temperature. The efficacy of boric acid at killing bugs sharply declines after adding it into the water, so in short spraying, a solution of boric acid for killing cockroaches and bugs is a poor method.

1. Sugar mixed with Boric Acid

The mixture of sugar and boric acid is quite effective at killing roaches. The sugar attracts, whereas boric acid kills. There are two methods to mix boric acid with sugar.

Making a paste

To create a paste, take 1 part of sugar and 1/4th of boric acid. Now start adding water until a semisolid consistency appears. Do not mix large quantities of water, making it difficult to use and affecting its efficacy.

Dry Mixture

The dry mixture is easy to use and is less messy than the paste. To make a dry mixture, take equal parts of boric acid and sugar and mix them with the help of a spoon.

You have to place these mixtures at specific points inside the house and wait for 2 to 3 days for the results.

The above recipe is good but has the disadvantage of attracting ants.

2. Flour mixed with Boric Acid

Flour is another alternative to sugar. The good thing about mixing flour with boric acid is its excellent bonding. Boric acid can either be mixed in dry flour or with dough. The dough can either be pre-formed or can be created after mixing with boric acid.

Mixing with Dry Flour

For this, take equal parts of boric acid and flour and mix them well.

Mixing with Dough

To mix boric acid with dough, take equal proportions of both and mix them well. Now add water slowly until a slimy dough is made.

You can also add sugar to the above mixture; It will attract cockroaches well. Now you have got the recipe. Next, place pieces of dough or sprinkle the mixture in a roach-infested area.

This recipe avoids attracting ants, so it is an excellent alternative.

3. Boric acid sprinkled on Bakery items

This recipe avoids the preparatory work of the above methods. All you have to do is buy some bakery items, e.g., Biscuits, donuts, or a cake and sprinkle a few grams of boric acid on them. Next, place them at the right places and wait for the results.

4. Mixed with Eggs

The aroma of eggs attracts roaches and palmetto bugs very well. When boric acid and sugar are mixed with eggs, it creates a killer recipe to which roaches are tempted.

To make this recipe, take one whole egg and 2 to 3 oz of boric acid mix them well along with three spoons of sugar. Leave the mixture in the open air for about 1-hour to let it dry. Once the mixture has got an excellent consistency, create cubes out of it.

Place the cubes around the corners of the house and wait for the magic.

5. Boiled Potatos

Boiled potatoes have a very tempting aroma and attract roaches better than other vegetables. This recipe is straightforward and has excellent results.

All you have to do is take 2 to 3 potatoes and cut them into small cubes. After that, place them in a pan and boil them until they are soft. Remove them from water and let them dry in the open air or with the help of tissue paper/cloth.

Once you have dry boiled potatoes, sprinkle boric acid on them and place the cubes around the house.

Does Boric acid kill cockroaches?

How long does it take boric acid to kill roaches?

Boric acid is pretty effective at killing roaches but is not a fast instantaneous solution. Boric acid takes between 2 to 3 days to kill cockroaches. If you are dealing with heavy infestation, do not expect results sooner.

Boric acid may take between 15 to 30 days to clear a milder roach infestation. Although you will start to see results soon in case of heavy infestation, you must wait for at least three months to see complete results.

Using boric acid also depends on the recipe being used, proper application, and placements. If you are using the wrong methods, you may not see any results at all.

Read the above article properly for attaining the best results.

Locations to put boric acid for roaches

It is essential to select proper locations for boric acid to work appropriately and effectively at clearing roach infestation. If you are placing boric acid in the wrong locations, your trick might not work well.

Cockroaches, including palmetto bugs, prefer certain places over others for hiding. These include:

  1. In bathroom behind the wash basin, inside cabnets, around the sink holes, behind the mirror and appliances.
  2. In kitchen inside the cupboards, around the sink, behind the fridge around the food and pipe lines.
  3. In bedroom behind the curatains, behind the furniture, inside the closet.
  4. In living room around the furniture and appliences, under the carpets and corners.

Give special consideration to garbage bins, loose food items, corners and cracks, leaking pipes, and a damp basement. Place boric acid in these locations to get the best results.

Is Boric Acid Harmful to Humans and pets?

Boric acid is a weak acid available in either crystalline or powdered form. Boric acid is a processed and refined form of earth mineral borax. Boric acid is toxic to pests, including cockroaches, and also has antiseptic properties.

Is Boric Acid Harmful to Humans and pets? Boric acid is very slightly toxic to humans and pets. Ingesting boric acid can cause skin irritation, nausea, vomiting, stomach pain, and diarrhea, which can be controlled effectively.

In case of ingestion, minor symptoms will resolve on their own. If symptoms are severe, consult an authorized physician.

Using boric acid around pets is usually non-toxic to birds, fishes, and invertebrates in smaller amounts.

When using boric acid, try to place it in corners and inside the cabinets, which are not somewhat exposed to pets and children.

Is it safe to touch boric acid? Yes! a smaller amount of boric acid is usually safe to touch. It is also used in skincare products as a stabilizer. When dealing with more significant amounts of boric acid, try to use gloves.

On the other hand, Borax usually irritates the skin and eyes and can cause rash and red-eye.

Does boric acid make roaches come out

When used, traditional chemical insecticide sprays make the bugs unstable, and they usually come out of their hiding places to escape the threat. The scene creates an unusual sense of distress among people as hundreds of cockroaches flood the space.

In contrast, boric acid kills palmetto bugs slowly and, therefore, is devoid of such effects. This creates peace of mind.

If you are not sure if you are infested with roaches or palmetto bugs, you can check this article on concluding palmetto bug infestations.

How long does boric acid last?

Boric acid effectively kills roaches until it stays on the surface in powder form. However, boric acid has two enemies, wind and water. Once the boric acid is blown away by wind or comes in contact with water, boric acid becomes useless.

Under average room humidity, the boric acid lasts for about four days before it catches enough humidity to render it nonfunctional. However, boric acid can last for 15 days to a month in dry summer months and keep killing roaches.

So it will be a good idea to replace the powder after every 2 weeks to effectively get rid of roaches with boric acid.

Borax vs boric acid for roaches

Boric acid is a refined form of Borax. Borax is a natural earth mineral found in seasonal lakes in California, Turkey, and Boran. The repeated evaporation in these seasonal lakes creates a layer of borax deposits harvested for boric acid. 

Both Borax and boric acid have the capability to kill cockroaches, but because boric acid is the refined form, it is superior. Therefore boric acid should be preferred over Borax as an insecticide.