Don't spend money on small pots to start seeds - just fill half an eggshell with a tiny bit of potting soil, drop a seed in, and sprinkle with water. If you save your egg cartons, you'll have the perfect holder for them. The best thing though is that when they are ready to plant you can put the seedling, eggshell and all, right into the soil. No transplant shock!
Fertilize Your Garden
Instead of throwing away eggshells, use them to fertilize the garden. Rinse and dry the eggshells and crush them with a spoon. Store in an airtight container and when it’s time to get the garden ready you can sprinkle and mix the ground eggshells into your garden for a great source of calcium carbonate for the soil. They reduce soil acidity. Tomatoes, peppers, and eggplants especially absorb the calcium from the eggshells. For maximum effect, sprinkle eggshells into each hole before planting. Then sprinkle additional shells around the base of your plants every two weeks to help with pests. (see below)
Use Eggshells to Deter Garden Pests
Eggshells are great for garden plants, but they can also help repel pests. Gather crushed eggshells and scatter them around your soil. This works as a natural deterrent for slugs, snails and cutworms. The jagged edges will do a number on the soft bodies of these pests if they try to cross them. And if your neighbourhood kitty uses your garden as a litter box, eggshells will help as well. Cats apparently have an aversion to eggshells and after stepping on those shells a few times, they'll decide some other garden is preferable to yours.