How to Add Eggshells to Soil

Toss eggshells into boiling water for two to four minutes. This helps kill bacteria, an important consideration if using the shells on indoor plants. It also helps remove any last bits of egg from the shell before it goes into the soil around outdoor plants. A large number of animals include eggs as part of their diets, so removal of the scent reduces the attraction of digging up the soil around your plants. You can omit this step and the next one if you plan to add eggshells to your compost pile. Just drop them into the compost bin.

Dry the shells after washing by leaving them out on the counter for a day or so. They crumble more easily when dry.

Crush the dried eggshells by hand, or grind them with a mortar and pestle. It isn’t necessary to achieve a powder at this point.

Place the chunks of eggshell into a blender or food processor. Pulverize them into a fine powder.

Sprinkle the eggshell powder around the soil near the main stem of each plant. Scratch the soil lightly by hand to work the powder just below the surface. If you composted the eggshells, add several handfuls of compost around the base of the plant.