Story and photos by Bruce Firger
The exterior covering of an egg— the shell—is about 95% calcium carbonate, which moderates soil acidity. The remaining 5% contains phosphorus, sulfur and potassium, all of which help to make plants healthy. The shell color of an egg varies depending on the breed of hen that laid it, and has no bearing on the mineral compensation of the egg. Eggshells are ideal for garden use. The U.S. food industry generates approximately 150,000 tons of shells a year.
So here is where we can fit in: Start at home and in your business to recycle the shells you generate.
The most direct way to utilize this by-product is to add the discarded shells to your compost bin, assuming you compost, or give them to someone who does.
Gardeners frequently add lime to compost to correct acidity problems in garden soil. Lime is made up of calcium carbonate, which is the main nutrient in eggshells.
The next suggestion on our list is to use them as a wonderful supplement to your plants and vegetables. This, again at its simplest, requires one additional step: After using the eggs’ content, run the shells under or through water and let them dry. Eggs are potential carriers of salmonella; make sure they are clean and free from bacteria.
Crush the shells in a zip-lock bag and use them for the following:
House Plant Booster—Keep a Mason jar of eggshells covered with water for watering indoor plants.
Planting—Place crushed eggshells in the bottom of empty pots before adding soil. Or place ground eggshells in the bottom of the garden hole you’ve dug before planting seedlings or germinating seeds. Then, sprinkle additional shells around the base of your plants and vegetables, inside and out, every couple of weeks. Outside this is also believed to deter slugs, snails and cutworms from chowing down on your veggies.
If you want to store ground eggshells for non-gardening tasks that are safe for you or your dog to eat, the powder can be used as a calcium supplement. Sterilize the shells by placing the dried shells on a sheet pan in a 200° oven for 30 minutes. You can then make a powder using a mortar and pestle, or let a coffee grinder do the work for you. Stored in an airtight container, eggshell powder will probably last quite a while.
OTHER USES INCLUDE:
Powdered Calcium Supplement—After baking and grinding into powder, use 1 teaspoon or less once a day in smoothies or juice.
Skin Tightening Facial—Whisk 1 teaspoon eggshell powder into 1 separated egg white. Apply to face. Allow the mask to dry, 15–30 minutes, before rinsing it off. Helping New Moms—Leaving crushed eggshells near your bird feeder will be appreciated by female birds. They crave extra calcium prior to and after laying eggs in the spring.
Irritated or Itchy Skin—Place an eggshell in a clean small glass container, cover shell about halfway with apple cider vinegar. Set aside for a couple of days, allowing it to soak and the shell to dissolve. Dab the mixture on minor skin irritations or itchy skin.
Abrasive Cleaner—Powdered eggshells make a wonderful (and nontoxic) cleaner for those tough-to-clean metal garden tools. Mix some with a little soapy water for a powerful clean that will remove mold and other nasty stuff. Cleaning Narrow-Neck Vessels—Add some crushed eggshells to the Thermos or other stained vessel, fill halfway with warm water and shake vigorously. The shells’ abrasive action will remove food stains. Rinse well with soapy then clean water.