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Boric Acid Roach Control

Summary: Borice acid roach control works. It's the all-purpose insecticide that does it all. Boric acid is used to kill ants, spiders, cockroaches, wood boring beetles, and fleas. Boric acid can stop and repair wood rot, too.

Boric acid is a colorless, odorless powder derived from borates that occurs naturally in soil, rocks, and seawater.

Besides pest control, boric acid has many uses that are very beneficial to mankind. It can be used as an antiseptic to sterilize wounds and as eye drops in a diluted form. It does everything from curing athlete's foot to treating vaginal yeast infections. It soaks up moisture and kills fungus which makes it good for treating wood rot. Boric acid can be used to prevent wood boring beetles, too. It is used as a flame retardant and even used in nuclear power plants to regulate the fission of uranium. It is practically non-toxic to humans,


mammals, birds, fish, and many beneficial insects such as bees.

And, if all those Boric acid uses are not enough, it can be used to kill fire ants, spiders, cockroaches, fleas, termites, beetles, and silverfish in widely available pesticides. The boric acid sticks to the legs of the insect when coming in contact with it, then the insect ingests it when grooming. It also acts as an abrasive on their exoskeleton.

Boric acid works slowly, it takes three to ten days to kill an insect using boric acid. This can be a good thing because boric acid is often combined with a food attractant in baits. The insect will eat a little of the bait, the boric acid sticks to them, and they carry it back to their nest where it spreads to the other insects living there.

Boric acid is effective in killing termites, ants, and cockroach colonies. too. It is available as aerosols, liquids, granules, wettable powders, dusts, pellets, and in combination with other ingredients as in baits.

To use boric acid as a roach control the boric acid should be applied into cracks and crevices in the kitchen, bathroom, and basement. Sprinkle some under the fridge, oven, dishwasher, microwave, and washer and dryer. It can also be applied above cabinets or between cracks in shelves. Basically, dust the boric acid powder into the small places where the roaches might like to hide. Under the kitchen sink between the water pipes is another great place to put it to


prevent roaches. Do not create piles of boric acid. It should only be applied as a thin film on the surface of the floor.

Boric acid can be used to get rid of fleas by putting it into carpets and dog beds. By working the powder down into the carpet you can kill fleas and the flea eggs. Vacuum the carpets thoroughly before you apply it and leave it in for a couple of weeks. It won't leave any stains.

One word of caution: Pregnant women should not use boric acid because of possible pregnancy complications. So, that means "heads up" on the following products: Flea Stoppers, Mop Up, Bora-Care, Jecta, Niban, and Timbor, plus others that contain boric acid. 

One more cool use of boric acid is utilized by jugglers and performing artists. When boric acid is combined with methanol it produces a bright green flame when it is burned. Just thought you would want to know this in case you were thinking about starting a flea circus and were looking for some great effects.

Ok, so that is Boric Acid. It's an all-around tool. Granted, it is not the fastest acting pesticide, but it is fairly safe for use around the house. As always, we urge you to carefully read the label of an insecticide and follow the directions.

Ask Rick A Question


16 Aug 2010, 00:09
It says "practically non-toxic to ..mammals"- can I or can I not use boric acid as treatment if I have a cat?

I obviously won't be licking the stuff but most likely my kitty would manage to ingest or inhale it. Is it safe?
Ask the Exterminator
16 Aug 2010, 14:25
"Safe when used as directed", and therein lies the problem. You didn't read the bold, red instructions about asking me a question, so why do I think you won't read the label on the boric acid!
06 Dec 2010, 15:47
I just moved into a new house which is 100 years old. We have noticed there are cockroaches in the house. I am 35 weeks pregnant is there a safe way of exterminating them?
Ask the Exterminator
06 Dec 2010, 15:50
The safest method for cockroach control is via cockroach bait products such as Maxforce bait stations and gel. You can read about these products at
25 Jan 2011, 13:29
I have recently seen roaches in my mobile home. We have lived here for 9 years with NO bugs but the landlord told us they recently had to have an exterminator on a home that is about 30 yards from ours. I am disgusted!! We keep a very clean home and no clutter, I'm borderline OCD with cleaning!! What is my best bet to kill these pest? I mainly see them in the kitchen and we have pulled out the appliances and sprayed and killed quit a few that way but I still see them! I'm ready to move!!!! Would a few bug bombs, including under the home, and putting down some boric acid do the trick??
Ask the Exterminator
25 Jan 2011, 14:34
It is doubtful that the roaches made the journey from your neighbor's home. You probably carried them inside in a box or bag.

Put away the sprays and bombs. The best way to control a roach problem is to use a product called Maxforce FC Roach baits. It's what the pros use. You will have to read the label to understand where the roach stations are to be placed and you cannot use the stations in conjunction with any liquid or spray pesticide. See the product at
26 Jun 2011, 10:03
I have boric acid powder when you say apply a thin amount on the ground how thin are we talking naked to the visible eye? I have hard wood floors and have been noticing roaches. Would the powder still be effective say if I swept it up and it's residue remained.Is the powder enough if I want immediate death or should I get the bait what popular stores have the bait. Are roaches attracted to the powder or only the bait?
Ask the Exterminator
26 Jun 2011, 10:48
You apply boric acid like a very thin coating of dust that would collect if you were a bad housekeeper. I prefer the baits, however. The baits that pros use can be purchaed on this website, but not in stores. Click on the "Pest Control Products" link at the top of this page. They're cheaper here, too.
25 Jul 2011, 08:04
This is a great article, very informative. The only thing I didn't see mentioned was Boric Acid removal such as, when should it be removed (after 10 days?) and the best method for removal (broom, vacuum etc). I referred this to a few friends who are investigating ant control. Thanks again for writing it.
Ask the Exterminator
25 Jul 2011, 09:48
Boric acid should be applied as a very, very, very fine dust. Get my drift? Most users apply mounds of the stuff, so they feel it necessary to sweep it up. If applied correctly, you can't even see it, so you don't need to sweep it up. It should remain in place as ongoing protection.
25 Aug 2011, 01:39
I swear by boric acid. Never tried the baits. I have neighbors on both sides who were and are swamped with the things, as in, they run all over the house in the day time, and eventually they must have worked their way over here.

Both neighbors are horrible slobs, and I am Mrs. Clean. Shocked at how fast they multiplied over here. After applying Boric acid behind appliances, cracks and crevices, and bookshelves (I never did put it in the middle of the floor), those cockroaches were missing in action after a month. Haven't seen them since. At least until the other day when the next door neighbor boy brought his Super Nintendo over... and cockroaches came flying out of it. UGH.
sharon greene
06 Sep 2011, 22:04
I just recently moved into a duplex that has roaches and I want to know should I call an exterminator or what iss the best pesticide that I can buy out of the store?
06 Sep 2011, 22:08
Sharon, the "Ask the Exterminator a Question" button is at the top of the page, and the article pretty much gives you the answer, but in my mind, exterminators in general can do no better than what this article tells you to do. Especially the boric acid. Get it at Lowe's or Home Depot or some place like that. Get the roach baits until then.
Ask the Exterminator
07 Sep 2011, 17:01
Sharon: I really like the Maxforce FC Gel Bait products found at this link:
13 Oct 2011, 09:07
I know boric acid works because many years ago I lived in military housing in Hawaii. The roach problem was enormous since the housing units were attached about eight units together. They always seemed to return until I heard about boric acid. I put a very thin layer everywhere I would find them especially behind kitchen appliances and bathrooms. I also puffed the powder into any crack or crevice that existed trying to get in between the walls. I took the final step of opening up what was a storage crawl space attic that connected all the units. I puffed the powder onto the insulation and anywhere I could reach. Shortly thereafter none of the units had any roaches and no child was ever again seen being carried away by those bugs. 
26 Feb 2012, 05:08
I used boric acid in bedroom behind bed and dresser. Bathroom toilet and under the cabnet behind frig and stove along wall in dining area. I also put bait statiion out to can i do this safely?
Ask the Exterminator
26 Feb 2012, 10:47
Most people make the mistake of putting out piles of the boric acid powder. It only requires a very light dusting of the product to kill insects. Read the label. It describes all the safety and environmental precautions.
28 Mar 2013, 20:19
My kids dad just got an apartment that has roaches in it, eggs too. He said he used boric acid along the cracks of the bottom of the walls and set 2 bombs off. Will this for sure get rid of them? There is also 3 other apartments in his building and nobody knows if theirs has been taken care of.
08 Apr 2013, 18:17
I have killed two adult wolf spiders in my basement. How can I get rid of them or deter them from coming in the house. Does boric acid kill wolf spiders? Whats the fastest way to kill them? Whats most effective?
16 Jun 2013, 17:53
I been using boric acid and after a new recent application of zap a roach I have pleghm and nowcould it be bad for the upper respitory system.tomorrow Iam going th emergency room I Ifeel like Ihave pneumonia.
28 Aug 2013, 21:50
Hello I recently found out I have anoiid beetles I did buy boric acid but I dont know how to apply it nor I don't know what bait should I use?? PLEASE HELP???
Ask the Exterminator
03 Sep 2013, 16:49
Powderpost beetles, especially anobiids, have specific moisture requirements for survival. Wood moisture levels below 13% (during spring and summer) are generally unsuitable for anobiid development or reinfestation. A number of insecticides are labeled for surface treatment of bare, exposed wood. Spraying or brushing these materials onto infested wood creates a barrier which kills adult beetles as they chew out of wood, and newly-hatched larvae attempting to bore into wood. The two borate formulations currently registered for residual surface treatment of wood are Bora-Care and Tim-Bor. Boric acid powder will not work.
29 Jul 2014, 03:40
I know it says not for pregnant women, but I have used it while pregnant & would again if I needed to. There is NO product to kill fleas that is okay'd for use by pregnant women, period. My husband was out of state on work, I was alone with a 2 year & did not have the money anyway to hire an we used Boric acid & it worked well. Even if I hired an exterminator, they aren't going to come back through & wash my clothing, wash my floors, wash my child's toys,etc...I'd have to do that & thus come into contact with a lot of chemicals anyway. I do understand that in lab rats, female lab rats showed some birth defects when exposed to super high doses of boric acid, but I can't imagine dusting your carpets would come anywhere close to that, especially if you are very very careful & use a help filter vacuum.

Just my 2 cents for what it is worth.
04 Mar 2015, 20:34
How will it kill spider's if they under table I moved in with a friend an I have 2small children theirs spider's an little roaches I downt want them on us they get in. An destroy everything an I cant sleep to protect kids the thought of one on me when I.sleep I boomed house didnt kill them
Ask the Exterminator
05 Mar 2015, 08:58
Boric acid won't kill any insect if the insect does not come in contact with it. Vacuum the spiders and knock down spider webs. Eliminate clutter. That is, by far, the easiest method of control.
18 Mar 2015, 11:11
I wonder what is the danger of poisoning myself ? In my car I'm afraid I've put piles of this stuff around the seats, top of front seats because nasty buggers seem to have infested them. I hadn't read this blog but even if I had it would be hard to believe a thin layer would do the trick. I nap in the car ... could I be getting close to the dangerous level of 4 mg/m^3 for inhalation ? I don't notice dust in the air. Apparently skin exposure isn't very dangerous. I've probably contaminated many surfaces although I can't see it.
Ask the Exterminator
19 Mar 2015, 11:43
Exposure to a pesticide is not healthy at any level. You need to vacuum thoroughly and wipe down all surfaces where human contact is possible. Rather than using a pesticide to control the bugs, I suggest putting out strips of double sided carpet tape to trap insects.
Mary K Johnson
25 Apr 2015, 11:15
I would like to thank you for your quick response if resolving the infestation of Carabid Beetles in my home.Your information has provided the best resolution for us. Thank you again !
E Green
20 May 2015, 20:46
Will a dusting of boric acid cause me any issues in the house while pregnant? I'm nervous the fine dusting could've been picked up by the ventilation system and is now in my air ducts.
E Green
20 May 2015, 20:49
Sorry I meant to specify a dusting in the attic.
Ask the Exterminator
20 May 2015, 21:09
I don't recommend using dust in an attic if you are uncertain about ventilation. The dust can seep into living spaces.
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