Use Eggshells and Egg Cartons for Starting Seeds
Give eggshells and empty egg cartons a second life in your garden. Use them as containers to start plants from seeds.
Fill the individual sections of egg cartons or the cleaned eggshells with a sterile well-drained potting or seed starting mix. Plant the seeds, moisten the soil and place the containers in a warm sunny location or under artificial lights.
Separate the paper egg carton cups and slice through the sides and bottom just before planting them into larger containers or outside in your garden. Crack the eggshells just prior to transplanting to make it easier for the roots to expand into the surrounding soil.
Move hardened off plants into the garden when the weather conditions are right for the plants you have grown. Using bio-degradable containers like these reduces transplant shock and adds organic matter and nutrients to the soil as they decompose.
A bit more information: Put other discards to work when starting plants from seeds. Many fast food containers provide a great vessel for starting seeds and a clear plastic top that can be used to create a mini greenhouse.