Fertilizer. Above: When tilled into the soil, ground eggshells provide your plants with calcium. Though nitrogen, phosphorus, and potassium are most vital for healthy growth, calcium is also essential for building healthy “bones”—the cell walls of a plant. ... More shells can be mixed into your soil in the spring.

Which plants like egg shells?

Plants like tomatoes, peppers and eggplants in particular will benefit from shell fertilizer, Savio said. The extra calcium will help prevent blossom-end rot. Broccoli, cauliflower, Swiss chard, spinach and amaranth are also calcium-packed and could use extra from eggshells.

Do eggshells keep bugs away?

Crushing eggshells for pest control is as easy as tossing your empty eggshells into a food processor for a few seconds or just rolling them under a bottle or rolling pin. After the eggshells are crushed, sprinkle them around the areas in your garden where you are having problems with slugs and other crawling pests.