Killing Roaches Part 3… Eradicating Roach Colonies With Diatomaceous Earth

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In my earlier posts about my roach killing expedition, I mentioned my discovery of Diatomaceous Earth. This non-toxic powder has the ability to kill roaches (and a whole bunch of other things) without poisoning them. It is microscopically abrasive and cuts and scratches the roaches inside and out. Since it’s not a poison, it doesn’t lose potency over time. So, one good application will last a long time.

Safe, non-toxic pest control - Eartheasy.comNOTE: Only use food grade diatomaceous earth or a product specifically labeled for pest control. The type of diatomaceous earth used for swimming pool filtration SHOULD NOT BE USED!

With a baby in the house, I was looking for non-toxic options for long-term use. This seemed like a very good product, so I started to hunt around for a local supplier. In New York City this wasn’t readily available (I didn’t have time to search around at gardening centers) so I ended up ordering it from Amazon. They also had a mint oil based non-toxic spray, so I got a couple cans of that as well.

When my 4 pound bag of Diatomaceous Earth arrived from Amazon I immediately set out to using it. I discovered a few things about how to best use Diatomaceous Earth in your roach killing efforts.

The first important thing to note is that, while Diatomaceous Earth is not poisonous to humans, it IS an irritant. It will get on your skin and dry it out like a mudpack. It has a mild, but noticeable, odor and it can irritate your eyes.

The second important thing to note is that Diatomaceous Earth will easily disperse in the air and form a cloud of fine particles that hang there a long time and then settle on everything in the room. This is not necessarily a bad thing!

Where To Apply Diatomaceous Earth For Effective Roach Killing

The goal with a product like Diatomaceous Earth is to get the roaches to track it back into the walls where it kills the roaches in the nest. A common application is to dust it under sink cabinets, stoves, refrigerators, and along baseboards. It is also good to spread it around outside if the roaches are coming from there (the powder in an outdoor application needs to be re-applied after rain.) I wanted to be even more aggressive.

If individual roaches tracking the Diatomaceous Earth into the walls was a good thing, I reasoned that coating the interiors of the wall with the powder would be even better – like a giant roach roadblock in the wall. I decided to drill small holes in the space between the wall studs in my kitchen and bathroom and blow the Diatomaceous Earth inside to coat the interior surfaces. A little drywall patching and paint afterward and I could relax in my own home instead of constantly scanning for roaches.

Applying Diatomaceous Earth For Roach Control

I got a plastic bottle with a cone shaped tip like those used for Boric Acid. Once filled with Diatomaceous Earth, I set out to dust under the refridgerator, stove, and along the baseboards in the kitchen. I tipped the bottle and squeezed it quickly to ‘puff out’ a little powder.

Safe, non-toxic pest control - Eartheasy.comI was concerned early on that the Diatomaceous Earth would clog up the bottle, but the fine powder dispersed nicely. However, I got a little aggressive trying to blow the powder back under the fridge and, when I looked up, I noticed the cloud of dust hovering in the kitchen.

Blowing the dust inside the walls turned out to be a much easier task than originally anticipated. Only a small hole was needed to get the Diatomaceous Earth inside and some vigorous work with the bottle created a cloud of dust inside the walls which coated every surface with roach killing powder – sweet!

IMPORTANT NOTE: Wear a mask when applying Diatomaceous Earth.

One nice thing is that the dust clings easily to many surfaces. So, the sides of the stove and lower cabinets are now roach death traps. In fact, the vast majority of the kitchen surfaces are now inhospitable to roaches.

I was pleased to discover that the following day the number of roaches spotted in the kitchen had declined noticeably. And, I saw a couple of them moving slowly with a coating of the Diatomaceous Earth on their bodies. I found a few more in the glue traps around the kitchen coated in dust.

Unfortunately, new horror kicked in when I realized the roaches were moving into the living room looking for new hunting grounds. The bedrooms were sure to follow. This was not good.

New glue traps were quickly placed in the major roach pathways in the living room and Diatomaceous Earth was dusted under some of the larger furniture and along some of the hidden baseboards to keep the roaches contained.

The second day after applying the Diatomaceous Earth, we had almost no roaches in the kitchen at all. I did the usually rattling of dishes and opening of cabinets designed to flush the roaches out of hiding and found nothing. This was all the more shocking given the fact that I had fallen asleep leaving dishes in the sink and before taking out the very full trash. While washing the dishes, one lonely baby roach came out of hiding and I quickly dispatched him with a shot of my mint oil spray!

If you have any tips or special techniques for killing roaches using Diatomaceous Earth, leave a comment below and let everyone know!

The Go-To Guy!

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Andrew Seltz

I was born in Michigan, raised there and in Tennessee, and have since lived near Orlando, in Chicago, and now in New York City. I produce videos and websites for a living and am married to a beautiful, generous, loving woman who also happens to be a talented actress -

65 thoughts on “Killing Roaches Part 3… Eradicating Roach Colonies With Diatomaceous Earth

  • March 1, 2008 at 11:33 pm

    Andrew, I feel more empowered to fight my personal roaches after reading your blog…thanks for the detailed account. My roach problem showed up about a year and a half after we moved into our house. I don’t know how they got in…I’m thinking via Costco boxes, or maybe my cleaning lady. It was in the middle of winter they started appearing. I’m thankful the infestation is in a very limited area (mainly the “wet and greasy” side of my kitchen where the sink and stove are) and I only see at most 3 or 4 usually when I turn on the light, sometimes none at all. I think the important thing is “constant vigilance” to keep them under control. Your techniques are great. Thnks again.

  • March 2, 2008 at 9:46 am


    I’m very happy to hear that my ordeal has given you hope. It’s not 100 percent over (we probably won’t have any hope of that as long as the ‘cat lady’ lives above us) but we’re no longer spooked by every movement we see out of the corners of our eyes.

    I encourage you to do 3 things, clean your stove like you’ve never cleaned it before (if it is free standing, pull it out and degrease the back and underneath), get some roach gel (if you can find a place that will sell you professional grade gel – get it) and place a bead of gel along all of the hidden edges of the stove where the roaches might walk (along the bottom edges, corners in the back, door hinges, etc.), and then seal every crack and crevice you find (around water and drain pipes, along trim and mouldings, cracks in the floor, switch plates and electrical covers too.)

    Sealing up the pathways where they move is extremely important. I saw the biggest change the day after I caulked all of the walls and cabinets. If you don’t know where they are coming from, place glue traps along the walls in the places you suspect and see where you catch the most.

    Another thing we started doing was spraying the counter tops at night with a mixture of 1 tablespoon of Tobasco sauce in 1 quart of water. Apparently the roaches don’t like the pepper and will avoid surface where it is present. We spray it around pretty generously in the kitchen at night to make the place as unpleasant for the roaches as possible. The spraying can give you a little sneezing fit while the mist is in the air, but the mixture is diluted enough to be unnoticeable once it settles and dries.

    Please leave a comment again when you’ve had a chance to test out some of these methods. Field reports are the best information.

    The Go-To Guy!

  • September 4, 2008 at 1:33 pm

    I get like one freaking GIANT roach looking thing avery couple of days? What do I do? They’re like 2 inches long, a reddish color and too big to squash unless you want to mop them up????

  • September 4, 2008 at 4:04 pm


    Sounds like you are probably dealing with an American Cockroach.

    The good news is that they don’t reproduce and mature as quickly as other roaches, so you are less likely to get over-run with them.

    The first step is to try and discover where they are coming into the building and seal off the entrance. Cracks along baseboards and holes around plumbing pipes are good places to start.

    Check for water leaks as well. Access to water is one of the main things that attracts roaches. Then, dust diatomaceous earth along baseboards, under appliances, and anywhere else where you think they might be traveling.

    Even if you stop new roaches from getting in, you will need to make sure and get rid of any that are already inside. To catch them, place glue traps along the wall edges that they are most likely to be traveling along. When the traps fill up, toss them and replace. Keep this up until you stop catching any.

    Let me know how it goes for you,

    The Go-To Guy!

  • September 9, 2008 at 6:35 am

    Andrew: Thanks a LOT for your site, it’s been really helpful in convincing me that roaches can be conquered. But do you have any suggestions for where I can buy a bottle with a cone-shaped tip like the one you used?

  • September 9, 2008 at 11:31 pm


    You are welcome.

    You can get Plastic Squeeze Bottles at You could also check your local craft store.

    I re-used a bottle from some Boric Acid I had bought and used up.

    Please come back and leave a comment when you get your problem under control and let everyone know what worked for you.

    The Go-To Guy!

  • May 26, 2009 at 10:44 pm

    Andrew: I was wondering if anyone has ever said if you can use this product for carpet Ants. I just killed a huge ant with wings on it. At first we just had black ants and we sprayed all around the house inside and out and now I have this big ant that looks like a bee but I went on line and looked up the pictures to make sure that is what it was. Sure enough that is what it is. So I am wondering if this would be a great product for carpet ants. Scared out of my mind.

  • July 25, 2009 at 1:22 am

    I have noticed that washing my counters nightly with bleach and the same with the inside of the cupboards usually on a weekly basis has helped with keeping my roach problem bearable, how ever after reading your article I have more to try to come as close to eliminating my roach problem as I can get since I live in an apartment complex good thing we didn’t through out the DE after filling in our pool.

  • July 27, 2011 at 5:27 pm

    well for all you new yorkers out there or people who have a hard time finding it just go to a pool store or a hardware store even cvs sav-on and rite aid have pool supplies and you get a huge box of it much better then a little box from a bug killing company.

  • December 3, 2011 at 1:50 am


    The pool filter DE is NOT the same. It has been processed in a way that alters it significantly. Only use food grade DE or DE that is labeled for pest control purposes.


  • August 4, 2011 at 1:01 am

    I know this last post from Joy was awhile ago but Oh Lord I hope she didn’t use the DE from the pool in the house! Only use the “Food Grade” D.E.

  • August 6, 2011 at 1:17 am

    If you’re wondering where to get a squeeze bottle to put your diatomaceous earth or boric acid in, try a beauty supply store. The squeeze bottles colorists use for dyeing hair work great. Just be sure to get one that is soft plastic and easy to squeeze so the powder comes out easily. The bottles that are made of harder plastic aren’t as easy to squeeze. Most of these bottles don’t come with caps, so I put slip a toothpick into the hole of the cap to keep moisture out. Good luck getting rid of your pests. I live in an apartment building where I have to be constantly vigilant because of the neighbors.

  • August 21, 2011 at 8:39 am

    I know this is an old article, but after reading Joy’s response, I had to make a comment for anyone else who may read this article.

    I am assuming the DE that Joy is using is POOL GRADE if she was using it for her pool. This is NOT the kind you want to use. You want to use FOOD GRADE DE. POOL GRADE DE is treated, which changes the chemical composition of the DE, so make sure you get FOOD GRADE DE ONLY!

  • December 3, 2011 at 1:47 am


    You are correct, thanks for sharing this information. I actually didn’t come across the availability of pool grade DE until long after I wrote this (not too many people have pools to maintain in Manhattan – at least not in the circles I traveled in, anyway.)


  • September 13, 2011 at 2:05 pm

    The DE you use in pool filters is not quite the same form of DE which Andrew is likely referring to. It can be harmful. The type used in pool filters is processed using high heat (calcining) …. which forms a much more crystalline version of DE. This more crystalline form can be harmful to Humans and animals, though is likely more harmful to arthropods (insects) as well. The type Andrew is likely referring to is classified as “Food Grade” DE. This form is processed using a passive drying processes which does not alter the physical form of the DE. It is safe for consumption and would not pose much of risk as a lung irritant.

  • December 3, 2011 at 1:44 am


    You are correct. I use food grade DE or grades specifically labeled for pest control use.

    Thanks for adding this clarification.


  • December 28, 2011 at 1:37 pm

    Hi. I have huge amount of cockroaches in my kitchen. tried everything from superstore and cleaning like insane. After i saw your blog tried DE but there is no impact on roaches at all.its been two days.please help how can I get rid of cockroaches. they are smaller in size and so many of them

  • January 27, 2012 at 10:11 pm


    Getting rid of them involves cutting of their food sources, getting rid of places where they can nest, and blocking their ability to move in and out of your walls.

    Based on your comment on their small size, they may be oriental roaches or recently hatched (or both.) That means they can squeeze through incredibly small cracks. So, the first thing you have to do is fill every single gap and crack in your kitchen.

    Most kitchens have huge gaps around the plumbing pipes under the sink. Check yours. There might be a metal ring around the pipes to visually cover the holes – pull them back and see of there are cracks and gaps around the pipes. Get some expanding foam insulation from the store and fill the cracks and gaps around the pipes.

    Next, get some clear silicon caulk and fill every single crack along the baseboards in the kitchen. Then, get some insulating pads to go behind the switch plates and wall outlet covers (these are designed to keep out drafts, but they work for roaches too.

    Finally, get some glue traps and place them along the walls on the floors and along the cabinets too. These will trap the roaches as they move around and help you to find out where they are coming from.

    I’m sorry to hear about your problem, but I know you can stop those nasty critters. Good luck,


  • March 19, 2012 at 12:26 am

    Help !! My son keeps getting water bugs in his garage! He sees them in street when walking dog so I guess that’s where they’re coming from. What can he use to get rid of them? These critters are tough! Thanks for helping!

  • March 28, 2012 at 1:47 am


    Garages are a tough place to deal with because there tends to be 2 big problems: easy entry through many cracks and gaps around the doors plus lots of places to hide.

    You mention your son has a dog. Make sure he is not leaving open food and water bowls in the garage. Dog food should be kept in an airtight sealed container and the bowls should be emptied between feedings.

    Next, if his garage resembles most, he needs to clean things up. Piles of boxes have to go. Items in the garage should be stored in covered plastic bins on shelves and not piled on the floor. Clutter gives the bugs places to hide and breed. If his garage is clean and orderly (or cleanup is done) move on to sealing off cracks.

    The seal on the bottom of the garage door might need replacing. Even better is to add one of those waterproof strips to the garage floor that creates a u-shaped channel for the bottom of the door to rest in. This creates a good seal along the floor which is a prime entry point.

    Check the seals around windows and doors. Fill gaps with caulk and replace worn seals. Any crack is enough to let them.

    I have similar issues around my current home. The bugs are most active at night – so he should minimize the amount of time the garage door is open in the evening when the bugs are active.

    Finally, apply diatomaceous earth along baseboards in the garage and in any place where the bugs might hide (under water heaters, behind shelves and workbenches, etc.) Poison baits placed in discrete corners are also good. And, in the garage, I would be fine also spraying some conventional poisons along the baseboards and around the entryways.

    I hope that helps,


  • April 4, 2012 at 10:40 pm

    Am I glad I came across thiss site!! I live in a mobile home community and in the last year and ahalf the roaches are getting worse! I’d like to get rid of them as quickly as possible, because my fiance is pregnant and we need a clean evironment for our new baby! I really don’t want any pooisons in the home and DE sounds like a good alternative. My fiance can’t stand bugs of any type and espacially a roach so I’m under pressure to get this under control. Funny thing is, they seem to be attracted to her and her things!! They seem to come out whenever she’s around. Even in the bedroom now and then. So as soon as I get some DE, it’s going all through the house and when we move, everything will be washes and cleaned, and the new place will be treated this way as well. In fact, I’m heading into the kitchen to spray the countertops with the Tobaco solution right now! Thanks for all of the tips.

  • May 6, 2012 at 8:30 pm


    Congratulations on the coming baby. I’m glad you are seeking out better pest control solutions to use in your house.

    I was motivated by the exact same concerns. My oldest daughter turned 1 when we moved into the apartment that turned out to be infested with roaches. She was into everything and I didn’t want to surround her with dangerous poisons. It took me a little time to figure out how to do it, but there are family-friendly solutions that work.

    I just put together a short book based on what I learned called, The Cockroach Assassin Report. The book covers how to shut down the pathways that roaches use to move through your home. I highly recommend following the process outlined before moving into your new place so any roaches that might follow you won’t be able to get into the walls of your new home.

    Good luck,


  • April 30, 2012 at 1:52 pm

    OMGOSH! I was laughing at your aggressive use of this dust as I am an AVID roach killer! I just noticed that I had and infestation about 3 nights ago. I bug bomb reguarly but am beginning to freak out about the effects of that stuff on all my food, so when I went to the tractor supply store looking for anything to help my battle the helpful clerk led me to this stuff. nothing much was written on the package so I went to the website and found only casual mention of it as a pesticide. I was beginning to wonder if I should return it when I came across you blog! I am so excited to get dusting and seeing the varmints die! I HATE roaches! I have not slept since finding them as the first night I styaed up all night unloading every single cabinet and cleaning and pulling out the stove and fridge. The following nights I keep getting up to go in and check the amount of roaches I see. When I am in bed, I am itching sure that roaches are crawling on me…so far every time I check there is nothing but I am still itching! So, Thanks for the info!

  • May 6, 2012 at 8:19 pm


    Sorry to hear about your bug problem. Bombing was not an option for me because the poison gets everywhere. I later found out it isn’t very effective either. The roaches retreat into the walls until the poison dissipates and then they come back. It is a short term fix at best.

    I recently went back through everything I learned about dealing with roaches and put together a special report I titled “The Cockroach Assassin Report”. It lays out my system, the products and home remedies I used, and some practical ways to restore your sanity during the process. Much of the information is in these blog posts, but I edited it into a bit more focused presentation and added a few extra bits I learned later.

    You can check it out here if you are interested:

    Good luck with your own Cockroach Assassin Efforts.


  • May 29, 2012 at 10:10 pm


    This is amazing. Thank you so much for all this useful information.

    Who would’ve thought that seeing a baby roach or two would lead to an enormous battle between me and their entire species! My life is consumed with trying to eradicate them from my LA apartment. And I was actually thinking that it was so ridiculous that I should write a book about it. And then I saw yours! Haha.

    For whatever reason, I’m the first complaint my building manager has received regarding a roach problem. Which is funny because I’m pretty clean. Although, I have to admit, whatever not-so-clean habits I’ve had is over since the roaches showed up.

    I just received my 2 massive bags of diatomaceous earth, which I’m so much more comfortable using around my 2 dogs. They’d been sneezing from the toxic killing sprays, till I decided I didn’t want to use anything that might hurt them!

    So, 2 massive bags of DE. I’ve just started using it. People are coming to seal up all the cracks & holes that I’ve found.

    I’m looking forward to not having to be on edge every time the sun starts to go down.

    I’ll look into the traps.

    OH!! And thank you for the info on the natural roach repellants! I’ve gotten bay leaves, garlic powder and catnip (boiled, placed in bottle & used as a spray).

    If any of those 3 have proven most effective, it was the catnip! Have you tried that?

    Maybe I need more bay leaves…

    But mint and pepper… I didn’t come across those options yet! So, I’m looking forward to adding more arsenal to my collection.


  • June 5, 2012 at 11:17 pm


    Sorry to hear that hear that you are having to go to war against cockroaches. As a veteran of that fight, I understand what it means.

    The good news is that you are starting with a much better battle plan. I’m confident that you will see major lasting improvements soon. Do get some glue traps. They are cheap, effective, and will help you discover where they are getting in and how they are moving around. I once spoke with the conservator of a rare book library who dealt with a nasty infestation and she said they were the most useful control tool she found (and she had trained university entomologists helping her.)

    I’ve moved away from the city (and apartment living) since I first wrote about this, but the stuff I learned is still useful. Just this afternoon I was using my diatomaceous earth to dust a few plants in my vegetable garden to control some caterpillars who have been shredding my collard plants. And, I’m planting catnip, mint, and a few other plants to help keep pests away from the house naturally.

    Good luck,


  • June 20, 2012 at 2:21 am

    DE works well, but if you ever want to get rid of roaches for a long period of time you need to hire an exterminator and find the nest. It is usually near a dishwasher or damp, dark area. When you find it, drop a bomb on it! In my apartment building in DC there were six major nests with thousands of roaches. The building has been roach free for over six months. And they spent money just closing up even the smallest holes with caulk and/or foam. In close quarters you have to be vigilant. We had to sign a waiver allowing them to dust your apartment every month. Worth it and I don’t care who complains. No roaches means a good night sleep for once in nine months without the nightmare of waking up and having a cockroach near you!

  • June 20, 2012 at 9:25 am


    You are 100% correct about needing to get to the source of the problem for long term results. DE is an awesome resource that is both effective and safe to use long-term. But, it is not magic (nothing is.) You have to take an integrated approach to get those lasting results (that’s what I discuss in the ‘Cockroach Assassin Report‘ I recently published.)

    I’m glad to hear that the people managing your building took the trouble to go through and caulk and seal cracks and holes. In my personal experience, that is every bit as important as any poison when it comes to stopping an infestation. When I moved into my current home, the very first thing I did was caulk and seal all of the openings around the plumbing pipes in the kitchen and bathroom – just as a precaution.

    Thanks for sharing your experience,


  • July 13, 2012 at 3:01 am

    I have been living at the same duplex for 3 years now and just discovered oriental cockroaches a year and a half ago. I bought diatomaceous earth earth and applied it and didn’t notice them for a long time. Then, to our horror, a few months ago we saw them in the basement and have seen only one in the bathroom upstairs, which I can only assume theyre dying from the left over powder from before. My problem is that there are cement walls in our basement which oriental cockroaches are known to dwell in. I am only able to put the diatomaceous earth on the floor around the walls. I read on another website that you can mix cocoa powder with the diatomaceous earth earth to attract them and they’ll take it back to the nest to destroy the others. I also read that they can live off of water alone. Where we live there is a washing machine drain tub that water comes from constantly. How do I keep them from surviving on that alone? Also, do you know how long it takes for them to die? I might consider doing laundry elsewhere for a small period of time to keep it dry there.

    So to break it down so you don’t have to go back through and read for questions:
    #1 How do you make powder effective if there are cement/brick walls where they dwell?
    #2 How do I kill them if there is a constant source of water?
    #3 How long does it take for them to die?

  • July 13, 2012 at 3:13 pm


    If your house is like most, the floor joist for the first floor are sitting on top of either a poured concrete foundation wall or a cinder block foundation wall. In either case, there will be a small area at the top of each wall where the two meet. I recommend putting DE powder all along this edge to kill roaches attempting to migrate up into the house.

    Adding an attractant to the DE powder is fine, but not needed if you can get it into the pathways they use to move through the house.

    Check for gaps and cracks around pipes going up through the floor. These are primary paths that roaches use to move through the house. Use caulk or spray-foam insulation to seal up any you find.

    Water is far more important to roaches than food. They can last a long time without food (and they can eat stuff you never thought of like paper and glue.) Rather than washing cloths somewhere else, you can pour some bleach down the drain after you finish washing cloths (that will kill any trying to crawl up through drains) and/or get a rubber drain plug to cover the opening when you aren’t doing wash. Just make sure to remove the plug before running the washer so you don’t flood the basement!

    If this is an unfinished utility space (which it sounds like) you might consider adding a bug bomb to your solution. I don’t like the idea of using them in living spaces, but would consider it in a basement or crawlspace. Bug bombs are a short term solution – still use the DE powder for long term control – but they will provide a quick kill that can help you get control of the situation. Just follow the manufacturer’s instructions.

    It is hard to say exactly how long it will take to get rid of all the roaches. But combining bombs, bleach, and DE powder should get fast and lasting results.

    I hope this helps. Let me know how things turn out for you.


  • July 16, 2012 at 1:21 am

    Thank you Andrew,

    I have roaches for the first time in my 7 years living in New York City and was concerned about bringing an exterminator in because I have two cats. I saw on one blog a recommendation of diatomaceous earth and quickly did a Google search on it since I’ve used it in the past for bed bugs (a whole other issue I hope nobody ever has to experience). I’m so glad it works for roaches as well because I was worried that by using boric acid, the cats would eat it and get sick.

  • July 16, 2012 at 3:32 am


    You are welcome. I hope the DE works well for you and the cats.


  • July 30, 2012 at 8:56 pm


    IF anyone is looking for Diatomaceous earth in Brooklyn and you happen to be a member of the Park Slope Food Coop, I saw some on the shelf there.

    Alex, I had a small question about the dust created, I was reading on wikipedia and it says that a big percentage of Diatomaceous Earth is Silica, from what i understand breathing in Silica is not good for humans, because silica particles stay lodged in our long tissue and after long periods of exposure creates silicosis in the lungs. Have you done any research on this? I read that you wear a mask when you are applying it, but isn’t the dust constantly being kicked around the house?

    I am going to buy it soon from the Coop and I am wondering about this.


  • July 31, 2012 at 1:14 pm


    I’m glad to hear there is a local source for DE in Brooklyn. I had a tough time finding in in Manhattan and ended up ordering it online.

    Silica is a common element that is used frequently in food production and sold as a food supplement (one study on silica found that increased consumption is correlated with a reduced risk of dementia.) Silicosis is most common in industrial settings with long-term exposure to highly refined silica. It comes from inhaling dust into the lungs.

    That said, you should take precautions when applying DE. Wear a mask, keep sensitive people and young children out of the area when working, and avoid aggressive application of the powder to minimize airborne dust. I personally restrict DE to areas under appliances, behind and under furniture, and other out-of-the-way places where it isn’t likely to be disturbed (except by passing roaches, of course.) If you have a forced-air heating and cooling system, keep the powder away from vents so the moving air doesn’t disturb the powder.

    Once the powder has settled, your exposure is minimal. Use common sense and follow any instructions and /or warnings on the package.


  • August 11, 2012 at 8:34 am

    Thank you Andrew!

  • August 11, 2012 at 5:49 pm


    You are welcome. I am glad I was able to help.


  • August 27, 2012 at 7:22 pm

    this may seem really mean and i have to admit it probly was; but i took a roach found on my floor this morning, upside down, and doused it in DE. it was still alive. i wanted to experiment and see what worked. i covered it so it was just a pile of white. i continued to watch and observe. What would happen to this bug? ive had roaches of all different sizes enter my dwelling, from 1 inch to 3 inches long. i have Orkin spray my interior and exterior every month, i sprinkle DE around everywhere inside. I dont appreciate them sneaking into my sanctuary. I live in Florida, there is plenty of water out there right now. it took about an hour for the bug to totally stop moving. So yes, DE works well. I got mine at Lowes. it was not more than $5 for the bag. adios cuckarachas!

  • August 27, 2012 at 8:06 pm

    Lynn Marie,

    That was a pretty intense experiment you performed. Just like you, I found DE to work and (most importantly to me) it was a long term option I was comfortable using.

    Florida is a challenging place for all the reasons you have mentioned. I now live in central Alabama and find many of the same issues – heat and moisture are at the top of the list. I keep a bag of DE handy for roaches and I now use it for pest control in my garden too.

    Thanks for reporting back on your results,


  • August 30, 2012 at 5:46 pm

    Thanks alot for your thorough info. I have lumber stored in garage and 1/2 of garage has a loose wall-to wall carpet. Is getting rid of all of that necessary? I do plan to throw away paper boxes; however, 1/2 of garage is my main storage area for a small house. How high do Oriental roaches climb? Thanks!

  • August 31, 2012 at 10:46 am


    Lumber piles are a prime nesting spot and the loose carpet can be a problem as well. The Oriental roaches can (and do) climb all the way to the ceiling. But, you can make this work!

    Using the garage for storage is perfectly reasonable, but they pose a special challenge. It is nearly impossible to ‘seal off’ a garage, so you have to expect that bugs will get in from time to time. If you are having roach problems, a few extra steps will keep them off your stuff.

    First, make sure everything is off the floor. Get some saw horses to hold the lumber (get rid of any wood that is damp) and buy/build some shelves for everything else. This will keep everything dry and minimize the pathways for roaches to get onto the stored materials. If you can keep the shelves pulled away from the walls it will prevent the roaches from moving from the walls to the shelves.

    Once everything is elevated, place DE, baits, sticky traps, etc. on the floor under the shelves to intercept the roaches trying to climb up. Garages are one place you can use moth balls which are excellent for repelling roaches (they hate the smell.) Follow the instructions on the label when placing them.

    I also recommend placing any items on the shelves into seal-able plastic storage containers. That way, even if the bugs do get onto the shelves they can’t get into your stuff. Those ‘Space Bag‘ vacuum sealed storage bags are great for any soft items like clothes, blankets, stuffed animals, etc. that you need to keep. They will keep out moisture, roaches, moths, etc. while shrinking the size of the stored items on the shelf.

    Another thing I recommend is to check the seals at the bottom of your garage door(s). The rubber seal on the bottom of most garage doors does a poor job keeping out bugs. There are usually large gaps at the ends and the middles often seal poorly as well. A seal like this one may help – specially if you have an older garage door and the seals are weathered.

    Don’t forget to inspect the seals around windows and side doors too. The fewer places roaches have to get in, the easier it is for you to control them.

    Finally, get into the habit of keeping the garage doors closed whenever possible.

    I hope some of these suggestions are helpful. Let me know how things work out for you.


  • November 29, 2012 at 1:27 pm

    I’m in a temporary situation in a trailor home in FL. I have a toddler and I have asthma and I’m allergic to cockroaches. I’ve seen more than a few in the past week and I’m totally freaking out to the point where I can’t sleep. I’ve got a lot of chemical allergies, so chemicals are not going to work indoors. I’ve got diatomaceous earth and have spread it around generously in the areas I’ve seen them. I want to avoid bringing them to the new house and get rid of the ones here. My questions are: 1) How likely is it that I’ll be able to get rid of them all here? 2) If there is no obvious food or water in the bedroom will they stay out of there? 3) Will using plastic bags for as much as possible, spreading DE in all boxes, and leaving everything we move outside (in MA in winter) for a day or two definitely prevent them from moving into our new home in MA? We are driving in our car with some stuff and using a moving company for the stuff in the storage shed. We’re going to repack everything. Please tell me my methods are foolproof.

  • February 12, 2013 at 12:11 pm


    I am so sorry to hear about your temp housing situation. Eradicating an infestation in a trailer will be tough – best to try and beat them back and focus on keeping them from hitching a ride to the new house.

    While nothing is foolproof, you are taking excellent precautions. Keeping things in the cold before bringing them into the new house will help. So will keeping things sealed in plastic while you are stuck in the trailer. If you can stand it, put some mothballs in the shed until it’s time to move. Roaches hate the smell and it will drive them away (I used them in my sink cabinets during the worst of my roach infestation in New York.)

    Before you move into the new place, make sure to seal all the wall openings around plumbing pipes and along the floors. Place glue traps inside cabinets, closets, and along walls in the kitchen and bathrooms. Finally, put DE in the basement or crawls spaces. This will help you catch/kill any stowaways from the temp housing before they can move in.

    If the new house has a garage, move as many of the boxes as possible in there first. Then, bring the boxes inside one at a time and unpack them immediately. Take the boxes and packing material outside as soon the the contents are removed. This will minimize the chances of stowaways entering the house unnoticed.

    Making the new place inhospitable will help keep the infestation from migrating.

    Good luck with your move. I know you can manage this.


  • March 23, 2013 at 3:09 am

    Hello. Do roaches carry the diatimacious earth back to the nest? If so, how long does it take to kill the queen?

    For two weeks I have tried your method and still see the occasional Oriental roach. Before that I had only sited the “occasional” one as well. In other words, the DE appears not to work at all.

  • March 26, 2013 at 10:18 am


    DE does work – I have used it to kill enough roaches to verify that. But it is not magic. DE kills by abrading and dehydrating the roaches, so it doesn’t kill on contact like a poison. But, it also never loses potency like a poison will. If you get it into the pathways the roaches are using to move through your home, they will track it though the walls.

    There is no ‘queen roach.’ Every female can (and will) reproduce. I used a combination of DE, glue traps, removing food/water/nesting materials, and sealing up cracks and holes in the walls that the roaches used to move through my home.

    Oriental roaches are a bit tricky, because they can walk up and down walls easily and often walk past the areas you’ve dusted with DE. It is very important to find out where they are entering so you can treat the area and seal the holes and cracks.

    Before you seal up large cracks (like the openings around pipes under sinks) blow some DE into the wall cavities. You can usually find gaps around electrical outlets and switches when you take the face plates off. You can blow some DE into the walls there too. That way, you will coat the surfaces that the roaches walk on when they are moving through the walls of your house.

    I hope this helps,


  • March 23, 2013 at 3:11 am

    also, if the bugs don’t carry the DE back to the nest, please tell me what roach killing product they will carry back to the nest. That’s what I’m looking for.

  • March 26, 2013 at 10:35 am


    The roaches won’t ‘carry’ the DE back to the nest as food. Rather, when they walk through it, it will coat their bodies and they will track it wherever they go. As they move, it scratches the waxy coating on their exterior which releases moisture from their bodies and dehydrates them.

    Most roach station poisons are designed to embed the poison in some kind of food. The roaches will carry that to their nests. But, poison baits alone won’t wipe them out.


  • April 18, 2013 at 11:10 am

    I moved to Florida eight years ago and about 3 years ago we moved into a house I purchased in the country. I have never seen so many roaches in my life! They are everywhere…in the yard, the walls, cupboards, in our furniture, on the ceiling. I am at my wits end! I tried bombing and I swear they came back out and laughed at me, because it did nothing at all. I have purchased a 50 pound bag of food grade DE and I pray it works. I will go ahead and put out glue traps and maybe throw some mothballs in the house’s crawlspace. As far as closing cracks and crevices, this is a 40 year old house, so there are cracks everywhere. Will the DE also work on the tons of spiders that have begun to creep into the house looking for a roach buffet?

    A Cleaning Fool

  • April 25, 2013 at 10:46 am


    Sorry to hear about your bug woes. Florida is bug heaven with its warm climate (they don’t mention that in their tourism brochures.)

    The DE should help with the roaches – not as much with the spiders. Put it in every crack and crawlspace you can manage. If there is a surface

    An older house is challenging for sealing up cracks, but don’t give up on the idea. Focus your efforts on the areas where you will see the most benefit. Bathrooms and kitchens are a good place to start (roaches are attracted to water). Seal the cracks around drains and water pipes under the sinks. Get the baseboards next. Check the seals and threshold sweeps on all the exterior doors and replace as needed. Every pathway you block will help.

    If you are not sure where the roaches are getting in, put some glue traps around the house. It will become obvious quickly where they are getting in.

    If all else fails, get a cat (or iguana.) They’ll hunt and eat bugs for fun.

    I wish you luck,


  • July 14, 2013 at 1:23 pm


    Did you mix Boric Acid with the DE or just puff in some of each. I have roaches in concrete block walls and am going to drill some holes and use powders. How is the Boric acid different than the DE?


  • August 20, 2013 at 12:17 pm


    I used each in sequence and did not mix them beforehand.

    Boric acid works as both an abrasive (like DE) and a stomach poison. There is significant overlap as far as what they do to control pest, so you would be fine to use either one by itself. I liked the way the DE dispersed and clung to surfaces and wanted the extra stomach poison aspect of the boric acid too.

    Good luck,


  • October 24, 2013 at 1:28 am

    I just purchased some DE to use around my mobile home. After a neighbor moved a trailer from next door to us, we became INFESTED….beyond infested. We’ve had multiple sprayings, bombed a few times….nothing has worked. Also, my elderly mother lives with me as well as a few pets and I didn’t like the idea of all those chemicals in the house. I started researching alternate Ideas. I haven’t tried the tobasco or the herbs yet but I’m going to, but I have started today with the DE. Unfortunately, as much as it needs it, I cannot plug our caulk holes and cracks….I live in an old mobile home that is older than I am….it is one of those places that needs LOTS of work, things like small holes are nothing. I have huge holes such as the bottoms of cabinets rotted out, etc. I don’t have the funds to fix them myself and my landlord won’t. I am going to have to hope I can control them when they come in, and your extensive article reassures me that at least I didn’t waste my money on DE 😀

  • March 31, 2014 at 4:14 pm


    Great info altogether, been reading up along the net for all kinds of ideas and like what I read here. Now to my dilemma…

    Former Cali resident with no roach problems I couldn’t handle, now in Texas where I’m just grasping the issues of roach infestations in a desert environment. House is mainly sealed up externally Looking at sealing internally as well (not there yet). Problem is not an internal issue rather an external one. I have no nesting internal and house is sterile at all times, garage too. At night they come out of the desert sands and migrate towards the house and find ways in. Previously, pesticides have been used externally and roaches that do make it in die that same evening, close to where they enter.

    I’m looking at using DE from here on out and I’m an ex-pool service technician. I know DE very well as a filter additive and how dangerous it is. Question is while searching across the net I feel I’m reading crossed messages. While I understand the importance of using food grade DE indoors, I don’t understand why pool grade couldn’t be used outdoors?

    My reasoning, I don’t have a garden or pets outside and from reading DE differences, pool grade has a greater percentage of silica than food grade(i.e. 2% vs. 60%). Now if the silica is cause of the irritant, wouldn’t a higher percentage be better for eradication? I’ve read elsewhere that pool grade DE does not affect roaches, but I can’t see how that’s possible. I guess the only thing that would occur is that they would die quicker?

    Just curious since I can purchase pool grade much cheaper the food grade if I plan on using it in desert sands. I mean really, would you pour food grade DE out in the desert (:

    Thanks in advance

  • July 12, 2014 at 2:03 pm


    I just discovered a roach in my bathroom last night–I’ve lived all over the US and I’ve never experienced this. I’ve lived in this apartment for 7 years and this is the first time I’ve ever seen anything like it. I mean, when everyone else was getting infested with stink bugs we had nothing at all. It was crazy.

    When I first saw it I wasn’t sure what it was. It was about an inch long. Not sure what kind of roach that would be. Probably American?

    Anyway, I literally went into panic mode, which was made worse when my teenager came home around 1 am and said there was one downstairs in the hallway. I grabbed my car keys and ran to Walmart and got DE. I should have grabbed some clear caulking but my mind was so focused on creepy crawlies that I never thought of it. I didn’t sleep at all. I’m pretty meticulous about being clean, but I totally emptied out my kitchen, pulled out the stove and refrigerator, and poured the stuff right into every single crack I could find. There are still some large holes under the sink and behind the stove, but I used Gorilla Tape as a temporary stopgap till I can call the building manager on Monday. Why do these things always happen on a weekend???

    This morning, I went into hallway armed with the DE and a measuring cup. Not even a spray bottle. I sprinkled it all along the walls and baseboards and even on the steps. Later this afternoon I’m going down to the basement, which is a big wide open area, and I’m going to treat that, too.

    And then we’ll see what happens on Monday when I call them.

    DE is the same stuff they use in flea and tick powder for pets. I have two cats, and the way I see it is if they accidentally get any on themselves, well, it’s a two for one deal! Kill the fleas and ticks, too. Actually, my one cat is how I found the roach. She’s an indoor cat, so since she can’t hunt rodents she hunts bugs. She’s given me decapitated spiders as “presents”. Well, she went right after this thing and terrorized it till it found whatever absurdly small hole it went into.

    I’m trying to figure out where they’re coming from, but my best guess is that they’re in the basement. There was a sewage issue about 6 weeks ago and if they didn’t take care of that properly (knowing them, probably not), well there ya go. It may just be a coincidence, but one of my neighbors just moved out as well and they were not the cleanest people in the world. They have not been back to clean their apartment and they’ve been gone for almost a month. I heard that they paid an extra month’s rent so they have till the end of July.

  • August 22, 2014 at 10:33 am

    The first place to check for entry points is water and drain pipe penetrations in the walls. Common construction practice is to cut the holes a little big and put a trim cover around the pipe to cover the gap. These covers are not sealed and leave plenty of space for roaches to enter and exit the wall. They can travel along the water pipes through the holes drilled in the framing. I recommend using spray foam insulation to fill the gaps (and you might dust a little DE in the wall before you seal it up.

    Apartments are tough. Your neighbors have a huge influence over the pest population. When someone moves out, pests go looking for a new food and water source. Any gaps in a shared wall can create an entry point. So, sealing gaps and cracks is a good first step.

  • March 2, 2015 at 2:42 am

    I am trying to figure out if there is a safe way to use DE to get roaches out of the microwave

  • March 26, 2015 at 12:55 pm

    I wouldn’t recommend dusting DE inside a microwave. It will mess up the motors and the cooling fans will blow it around every time you turn on the microwave.

    If they are inside the electronics, you will probably need to open it up to clear them out. If the microwave is mounted over the stove, you’ll have to take it down. If you are not comfortable around electronics, or have trouble lifting and moving things, enlist help.

  • May 28, 2015 at 8:20 am

    Hi Andrew, so glad I found this page! I have only seen one live roach(which was caught in spider web in garage) but am finding droppings, similiar to mice droppings (only smaller) on bath towels. The towels are in an open rack… I have set traps for mice thinking that may be problem, only to find peanut butter gone in the morning with trap still set. So my question is if its normal to see the droppings & no roaches? Also found them(droppings) in a few drawers which I emptied & cleaned, then put roach bait & glue trap inside but of course no activity there. Im wondering if theres another critter or bug around or are the roaches hiding well? Thanks!!

  • June 28, 2015 at 12:47 pm

    Thanks for this post, Andrew. My girlfriend has similar roach problems and after several attempts bug bombing her place (which I was highly opposed to) I convinced her to give DE a try. I’ll let you know how it goes, but we’re just starting this war on those little vermon.

  • August 19, 2015 at 7:13 pm

    Thank you for the info about DE. We have an asthmatic in the house…do you think if I apply it around the house while he is out for a few hours, that it will bother him?

  • September 21, 2015 at 3:24 pm

    Once the DE settles, you shouldn’t have problems. Just make sure to avoid applying it to areas where there will be air disturbance. Avoid air vents, etc. so that you don’t stir up the DE after it has settled in place.

  • August 30, 2015 at 3:23 am

    I’m a pest controller in London and have a problem with American cockroaches infesting kitchen drain sumps. We need to avoid contaminating the drainage water system with our usual range of insecticides ( stated on the label ) so I was thinking about DE applied beneath the drain covers and down the sides above the drain . We don’t want to excite the adults into movement to other more obvious areas and it’s hard work lifting the covers so we don’t often have access . Any ideas please ?

  • September 21, 2015 at 3:33 pm

    DE is not going to be a good solution for wet areas. The moisture will cause the dust to cake and then it will not stick to the roaches as they walk over it.

    I have not encountered a directly similar situation, so I do not have a specific recommendation. You will likely have better results devising a bait trap that will adhere to the underside of the drain covers and deliver a conventional insecticide.

  • November 12, 2015 at 11:35 pm

    I found a large watercolor brush I have works great for dusting DE in kitchen cabinets, shelves, around stove etc., since I didn’t have a garden duster.

  • December 14, 2015 at 6:21 pm

    Laurel, that’s a good idea. I’ll bet one of those big makeup brushes for applying loose powder would work just as well.


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