Searching for an inexpensive way to drive away pests from your yard? Do you know that with eggshells you can prepare excellent natural pesticides for killing slugs, beetles and other common pests that invade your garden and damage your plants? Eggshells work in the same way as diatomaceous earth. It works by puncturing the shell of bugs that dehydrates the insects and kills them. As eggshells are natural they are the best non-toxic pesticides that you can use at home. To prepare the eggshell pesticide, grind the eggshells in a coffee grinder and sprinkle the powdered shell in your garden. Apart from killing the pests, the eggshell powder will also add calcium to your garden soil.