A broad-spectrum organic insecticide that is so safe you can eat it, let’s study diatomaceous earth and its benefits and uses in gardening.
What is diatomaceous earth?
Diatomaceous earth or in short DE is a very fine powder. It is made from the fossilized remains of tiny aquatic organisms called diatoms.
While there are different variants of diatomaceous earth used for various purposes you want to make sure that for gardening purposes you want the food-grade DE.

Types of DE:
- Granulated (for packaging)
- Calcined (for filtration)
- Micronized (for gardening)
Here is a commonly available food grade diatomaceous earth product. You want to buy a product which also comes with an applicator and we’ll soon see how to apply this product.
Although it looks like a fine powder, under the microscope diatomaceous earth looks like many barbs or shards and this is what makes it very effective on two classifications of organisms. So let’s look at what DE controls.
What diatomaceous earth controls? (Benefits)

Arthropods like aphids, corn earworms, mealybugs, spider mites, tomato or tobacco hornworms, and whiteflies.
Gastropods like snails or slugs, although it’s less effective against them since they are in wet environments which is not very conducive for diatomaceous earth to work.
But this should give you a good idea of what insects the DE controls and what it does not. Now let’s look at how to apply diatomaceous earth.
How to apply DE?

It’s highly recommended that you wear a mask during the application, although it is safe to humans it does irritate the nasal passages and yes you shouldn’t be breathing in any form of dust anyways so wear a mask.
We will be using an applicator that makes easy work of spreading the diatomaceous earth on the plants.
Fill up the applicator container and you’re ready to roll. By using the nozzle pointing up you can get a fine cloud of DE on your plants.
Pay attention to the wind direction. The wind is blowing towards us so we start spraying in the other direction where the wind is blowing away from us.
In our vegetable garden, we use diatomaceous earth to control aphids and spider mites very effectively. Use it once a week when you start seeing these insects or pests in your garden.
Now by turning the applicator upside down you get a larger amount of powder, dust the plants thoroughly. We also use it on our container plants and this is great for plants like okra and eggplants where you want adequate coverage to control aphids as an example.
How does diatomaceous earth work?

The way diatomaceous earth controls arthropods is that it removes lipids or fats from their exoskeleton and the arthropods eventually shed it causing it to dry out and they die or they become easy prey to predators like birds etc.
Does it work on ants? Well technically yes. But there are better methods to control ants which we’ll probably look at in a separate article and ants don’t usually cause any damage to plants except that they protect aphids but generally they’re not too much of a problem.
If you have a lot of rain or a lot of water on your plant’s diatomaceous earth will not be very effective, you need a dry environment for DE to be effective.
And yes technically you can mix it in water and spray, but it will only be effective once the water dries out and the DE is in its dry form.
Diatomaceous earth takes about 36 to 48 hours to take action. You want the insects to crawl on it for it to be effective.
You can rinse off the excess powder of the plants for getting your garden aesthetics back.
Beneficial Garden Insects

Now you may be asking whether diatomaceous earth affects beneficial insects like bees and ladybugs? Yes to some extent. If you apply the product early in the morning or late in the evening when bees are less active they will try to avoid the dust later that’s the best you can do and you’re not intentionally harming them.
But overall it is still a relatively safe product in fact extremely safe for humans and pets they’re also used on pets to control fleas as an example.
So all in all it’s a great product it’s an organic product that will let you control a wide range of insects in your garden.
So there we have it that’s all you need to know about this wonderful product called diatomaceous earth. Do you use this in your garden? Do let us know in the comments. Make sure you share it with your friends, it’s a great educational article which no one should miss. Happy gardening!