Eggs are nutritious bundles of vitamins and minerals, and can add organic nutrition to compost or planting soil. Tomato plants don't need the entire egg, though, and thrive with just the shells. Eggshells contain nitrogen and calcium for growth, and calcium carbonate for the prevention of blossom end rot.
Prepare eggshells before you put them outside in the garden. Crack the eggs and keep the eggshells for the outdoors. Scoop the membrane out of each shell, and then rinse the shells in warm, clean water. Once the shells have dried, crush them into fine chips and dust them with the base of a cup.
Turn the eggshell dust into your tomato planting soil with the standard soil amendments. Dig into the top 10 inches of natural soil, add 4 to 5 inches of organic compost for nutrition and soil quality and add 6-24-24 or 8-32-16 fertilizer for root growth. Mix eggshell dust into the top 4 inches of soil as your final soil amendment.
Use eggshells throughout the season for continued protection and nutrition. Pour the water from boiled eggs into the soil of the tomato garden for a boost in calcium, nitrogen and calcium carbonate. Sprinkle large pieces of eggshells around the garden and individual plants to keep out slugs, snails and cutworms.