Each time you crack an egg open, instead of tossing the shell into the trash, drop it into an open container that you keep in the fridge. When the container is full, crush the shells into small bits and sprinkle them around the base of your plants. The sharp eggshells will deter slugs, snails, and other bugs from nibbling on your garden and add a touch of calcium to the soil.
Use Old Coffee Grinds in your garden. Tomatoes love it!! They add nitrogen to the soil, boost foliage growth and deter pests. If you dont drink much coffee, Starbucks gives away coffee grounds in their Grounds for Gardens programs.