Diatomaceous earth (aka, DE) is a naturally occurring, soft, chalklike sedimentary rock that is made from tiny, fossilized water plants and can be easily crumbled into a powder. In its powder form, DE dehydrates an insect's exoskeleton, killing them, so it makes a great nontoxic pesticide. You can disperse DE around your garden to protect your plants. To do so, fill a large spice shaker with it and dust it around the soil of your plants. Try Earthworks Health to order diatomaceous earth and a dispenser, if you need one.