This is the coolest idea for herb seedlings ever! I saw this on one of the gardening posts on Pinterest. Save the empty egg shells, let them dry out a bit then add potting soil-compost mix. Plant the seed, water with a spray bottle, and then set the egg in a carton. Plant the egg and all outside when the weather permits.
It's a great way to start seedlings and give them the calcium they need. especially tomato plants. Also to label the seedlings, take a tiny strip of paper, write the seed type on it and tape it to a toothpick. Then stick it into the soil of the seed. Set the egg carton on a warm window sill. Use a spray bottle to keep the plantlings watered.