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If you’ve looked much into bed bug control, you’ve probably come across diatomaceous earth as one possible solution to killing bed bugs. Many people end up using diatomaceous earth because it’s much more safe and more natural than chemical sprays or other alternatives.
As an added benefit, this miracle dust kills other insects like ticks, fleas, roaches, spiders, and even more!
Let’s talk a little bit about what diatomaceous earth is and how to best make use of it for pest control.
What is Diatomaceous Earth?
Diatomaceous earth is made from ancient, fossilized single-cell algae made largely of silica. These silica deposits are mined from areas like river banks and then dried. Diatomaceous earth has a wide variety of uses but to the average person, the most common use is pest control.
What makes diatomaceous earth uniquely useful for killing insects are two key properties.
- It absorbs lipids. Many insects have a waxy outer coat to their exoskeleton which helps them maintain moisture in their body. When insects come into contact with diatomaceous earth, that waxy layer gets eroded and most bugs die of dehydration over the span of days to 2 weeks.
- It’s sharp and jagged. These fossilized remains are not smooth or rounded. At a microscopic level, they’re full of sharp, jagged edges that make it easy to latch into insects that it comes in contact with. This helps diatomaceous earth damage the exoskeleton more as it sticks to the bug, sometimes transferring to other bugs that come in contact.
While diatomaceous earth may be fatal to insects, it’s actually safe for human consumption. You can find “food grade” diatomaceous earth which means that the product has been sterilized, so no harmful bacteria is in the product. Diatomaceous earth is often used as an additive when storing grain or in livestock feed.
Diatomaceous Earth Safety
Diatomaceous earth is a naturally occurring product and has no toxicity like chemicals do, but you still want to handle it with care. While it won’t cut you or hurt you, it can dry out your hands so you should use gloves when handling it.
The bigger concern though is breathing it in. You never want to inhale fine, foreign particles into your lungs. The common form of diatomaceous earth sold today is not known to be a carcinogen but you could still irritate your lungs, eyes, and nose membrane if you’re having a lot of the product go airborne.
Most of the time this shouldn’t be a real concern, but you should still wear proper safety gear like goggles and a mask when handling.
Applying Diatomaceous Earth to Kill Bed Bugs
Using diatomaceous earth to kill insects like bed bugs isn’t difficult, but there are a few things you should know and be aware of to get the most out of it.
Methods of Application
Diatomaceous earth is a powdery substance. It’s not a liquid you can squirt out of a bottle like most chemical sprays, yet we need to lightly and evenly distribute it for it to be effective.
The most common and effective way to do this is by using a powder duster. A powder duster is basically a handheld device where you load powder into a chamber, and lightly squeeze the chamber to shoot powder out of the narrow spout.
This gives you a lot of control over how much powder to disperse. You can get close to your target to keep the powder more concentrated or pull the duster back more to let the powder spread to cover a wider target more lightly. Here’s a duster I recommend –
Another way of applying diatomaceous earth is with a dry, flat paintbrush. You wouldn’t want to do this to cover a lot of areas, but if you’re looking to get diatomaceous earth into cracks and crevices that may be hard to reach it’s a great option.
A paintbrush may also be useful when you want to keep the amount of powder to a minimum. For example, if you’re fighting bed bugs, you may want to apply a controlled amount of diatomaceous earth to the creases of your mattress and a duster would likely be too much.
One key thing to remember is that you want the bugs to come into contact with the diatomaceous earth. This means you want to keep it spread thin so it doesn’t look like an obstacle it will move around.
If you spread out too much, you can always vacuum it up. I recommend a good vacuum with a HEPA filter to prevent irritants from being spread into the air.
While the dry application of DE described above is the most common and easiest way to go about it, it’s also possible to apply diatomaceous earth in a wet form. To accomplish this, mix diatomaceous earth and water in a 1:4 ratio (1 cup of diatomaceous earth, 4 cups of water). Then you can spray this mixture through a spraying applicator.
I wouldn’t recommend bothering with a wet application of diatomaceous earth unless you have awkward areas you’re trying to get into or cover that a powder duster isn’t working.
One common use case is applying DE to the underside of surfaces or vertical surfaces. A powder isn’t going to stick well in that situation, but the water will stick and leave the DE behind when it evaporates.
One other drawback of wet application – diatomaceous earth is not effective at killing insects while it’s wet. It needs to dry out before it will start to kill bugs.
Where to Apply the Diatomaceous Earth
The first thing to know is that bugs must come in contact with diatomaceous earth in order for it to kill them. You want the diatomaceous earth to be in areas the bugs are already using or in areas you suspect they may live, travel across, etc.
This also means that diatomaceous earth doesn’t work well with repellent insect products. If you apply a bug repellent in the same place as diatomaceous earth, the diatomaceous earth isn’t going to do much since most of the bugs won’t come into contact with it.
Spreading the diatomaceous earth around everywhere isn’t going to be very effective and a good use of your time. Try to apply it strategically. For bed bugs, this means the areas around your bed.
Try to get the power under your baseboards, around the feet of your bed, under the edges of the carpet (if possible), and even behind your electric outlets so the powder can get into wall crevices (be sure to turn off power to the outlets while you work).
You may also want to work some diatomaceous earth into cracks of your headboard, dresser drawers, bed frame, box spring, and mattress.
One thing to note is that diatomaceous earth is only effective when it remains dry. As a result, it isn’t the most effective product to use outside of the house and if you did, you’d have to re-apply after rain or high humidity days.
How Long to Use Diatomaceous Earth?
The nice thing about diatomaceous earth is that it works on a physical and not chemical level. It doesn’t break down and lose effectiveness over time as long as it remains dry, so one treatment should last you a very long time.
You can vacuum up any diatomaceous earth hanging around when you’re done with treatment though most of it will be in cracks and crevices that a vacuum won’t reach which is just fine. It won’t do any harm to let the diatomaceous earth sit there and act as a killing agent for other pests that may try to invade your home.
Pest Control Alternatives
If you’re not sure about trying this DIY extermination method and would rather have professional eradicate your beg bug infestation, we recommend getting a quote from our top national exterminator picks.
Diatomaceous Earth for Bed Bugs FAQ’s
Is diatomaceous earth safe for dogs/cats/humans?
Yes, diatomaceous earth is largely considered safe and non-toxic for all creatures in your home (except pests). “Food grade” is even safer as it has been sterilized to remove possible bacteria mixed in. You wouldn’t want anyone to inhale fine powder though as it could irritate the lungs.
What insects does diatomaceous earth kill?
Diatomaceous earth kills basically all bugs including bed bugs, roaches, ants, ticks, spiders, fleas, slugs, silverfish, beetles, centipedes, etc.
What kind of diatomaceous earth is best for bed bugs?
Any diatomaceous earth you buy today is likely the same stuff just in different packaging. We recommend getting “food grade” but we are not aware of any issues that have come from a human or pet ingesting any kind of diatomaceous earth.
Is it safe to sleep in a room that had diatomaceous earth applied?
Yes. Diatomaceous earth should be applied wearing a mask since it’s a fine powder, but once it has settled there’s no harm from being in the same room as it. This goes for pets and children as well. DE should settle within seconds of being applied, so there’s no worries about using it in bedrooms.
Do I need to reapply diatomaceous earth? How long does it work?
Since diatomaceous earth works on a physical level, it doesn’t break down after weeks/months like chemical pest control agents. You shouldn’t need to re-apply diatomaceous earth until what you put down got washed away or vacuumed up.
Can I vacuum up diatomaceous earth?
Yes, you can vacuum diatomaceous earth but may want to only use a vacuum with a HEPA filter or a wet/dry vac. Since DE is a fine powder, it’s possible that it could get through cheaper vacuum filters and reduce the effectiveness of the vacuum motor over time. A high-quality vacuum such as Dyson vacuum cleaners should be able to handle vacuuming up diatomaceous earth without a problem.
Does diatomaceous earth still work when it’s wet, or if it gets wet?
Diatomaceous earth does not work when it’s wet, but it will work again when it dries assuming it wasn’t washed away like in the case of rain or a heavy pour of water.
Can diatomaceous earth be used outside?
Diatomaceous earth can be used outside, however, it likely won’t be that effective over long periods of time. For one, it needs to be dry to kill bugs so in humid environments or during rainy periods it won’t do much. Also, rain can wash the DE away or bury it in the soil.