Start your seedlings
Fill the shell halfway with soil, carefully place your seeds and wait for them to grow. To keep the eggshells safe, you can put them into empty egg cartons.
When the plants are large enough, you can transplant the whole thing to the garden, where the shell will break down, providing added calcium to the soil around it.
Deter garden pests
Use roughly crushed eggshells around the base of plants to deter snails and slugs who are trying to devour your gardening efforts.
Add them to compost
Lots of plants love calcium so add some to your compost to improve its quality. Mix into the compost before planting to revitalize, add nutritional value and improve drainage.
Give your houseplants a boost
Keep a jar of eggshells covered with water, for watering indoor plants andfor a nutritional boost.