Next time you whip up a quiche or bake a cake, you may want to think twice before tossing the eggshells in the trash. From deterring pests to making better coffee, practical uses for eggshells abound. Note that, except when using them in the garden, raw eggshells should be sterilized before using. To do this, place the shells in a pan on the stove, cover them with water, boil for 5 minutes, and let them completely dry on a cookie sheet.
Eggshells make perfect biodegradable containers in which to start seedlings. Tap the small end with a spoon to crack it, then carefully remove the top and empty the egg. Use a funnel or spoon to scoop potting soil into the shells. When the shell is nearly full, use tweezers to gently plant seeds just below the surface of the soil. Place the eggshell planter in a carton in a sunny window, and gently mist the plant daily. When your seedlings are ready to plant outdoors, simply bury the entire eggshell. The shell will break down and provide extra nutrients for your plants.
Perhaps the most obvious way to reuse leftover eggshells is simply including them in your compost. Eggshells are an excellent source of calcium and micronutrients for plants. Crumbling eggshells and adding them directly to the soil is helpful, too. The added calcium can help prevent plant diseases such as blossom end rot in tomatoes.
Brewing coffee with eggshells can reduce its bitterness. After sterilizing, add crushed eggshells to coffee grounds and brew as normal for a cleaner, milder-tasting cup.
Eggshells can form the basis of homemade sidewalk chalk. Using a mortar and pestle, crush sterilized eggshells into a fine powder. In another bowl, mix 1 teaspoon flour and 1 teaspoon hot water. Add 1 tablespoon of eggshell powder and mix into a thick paste. Use food coloring or natural dyes to color the paste, then shape it into a stick by rolling it up tightly in a paper towel. Let it sit for three days, then the chalk is ready to use!
Suffering from hives? Try relieving itchy, troubled areas with eggshells. Dissolve an eggshell in a small jar of apple cider vinegar for about two days, and apply the mixture with a cotton ball to treat minor skin irritations.
Thanks to their abrasive qualities, eggshells can help thoroughly clean water bottles or vases. Simply add crushed sterilized shells and a little soapy water to the vessel you’re cleaning, and shake. Crushed eggshells can also be used as a nontoxic scrub for pots and pans.
Sterilized eggshell powder is digestible, and can be added to homemade food or treats for pets to keep their bones and teeth strong. One teaspoon of eggshell powder contains roughly 800 mg of calcium. To find recipes for natural homemade dog and cat food using eggshell powder, visit Homemade Pet Recipes for Dogs and Cats.
Soft-bodied critters such as slugs and snails don’t like crawling over sharp, uneven eggshells. To keep these unwanted visitors away from your plants, simply crush the shells and spread them around the base of plant stems.