Eggshells have a variety of uses across different domains, from gardening to household applications and even eaten as a calcium supplement.

Gardening

Fertilizer: Crushed eggshells add calcium to the soil, benefiting plants such as tomatoes, peppers, and eggplants.
Pest Control: Sprinkling crushed eggshells around plants can deter pests like slugs and snails.
Seed Starters: Eggshells can be used as biodegradable seed starters. Fill half shells with soil and plant seeds in them. Once seedlings are ready, the whole shell can be planted in the ground.

Household

Cleaning Agent: Crushed eggshells can be used as an abrasive cleaner for pots, pans, and other hard-to-clean surfaces.
Drain Cleaner: Ground eggshells can help prevent clogs and clean drains when flushed with hot water.

Personal Care

Skin Care: Ground eggshells can be added to homemade scrubs or masks for exfoliation.
Health Supplement: Eggshells are beneficial for humans, consisting of 95% calcium carbonate, making them very similar to our own bones and teeth. After proper cleaning and processing, eggshells can be ground into a fine powder and used as a calcium supplement.

Crafts and Decorations

Arts and Crafts: Eggshells can be used in mosaics, ornaments, and other decorative projects.
Eggshell Chalk: Crushed eggshells can be mixed with flour and hot water to create homemade chalk.

Animal Feed

Chicken Feed: Crushed eggshells can be fed back to chickens as a calcium supplement to help them lay stronger eggs.

Environmental

Composting: Eggshells are biodegradable and can be added to compost piles to enrich the nutrient content of the compost.

Miscellaneous

Whitening Laundry: Adding crushed eggshells to a mesh bag and placing it in the washing machine can help whiten clothes.
Reducing Coffee Bitterness: Adding crushed eggshells to coffee grounds before brewing can reduce bitterness.

These diverse applications make eggshells a valuable resource that can be reused in various sustainable and practical ways.