How To Repurpose Eggshells For Thriving Lavender Plants

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When caring for the menagerie of plants in your garden, you may find that lavender is a bit of an odd duck. Unlike a host of other flora, it doesn't love soil that's rich in nutrients and slightly acidic. Instead, it prefers slightly alkaline pH and zero NPK fertilizer, a common garden revitalizer whose nitrogen can lead to fewer lavender flowers, a weaker aroma, and increased disease risk. The only nutrient lavender likely to crave is calcium, which reminds it of the chalky soils of its Mediterranean homeland. They tend to contain lots of this mineral. You can boost the calcium content of your lavender's soil for free by incorporating eggshells, which are primarily composed of calcium carbonate. If you prepare and disperse them correctly, they'll gradually deliver calcium to your lavender while enhancing your soil's structure and raising its pH level slightly. Since the shells take a while to break down, the key is convincing them to release calcium sooner rather than later.

Before incorporating any amendments into your garden soil, perform a test that measures nutrient and pH levels. This will tell you what you should add and how much you're likely to need. Contact a local cooperative extension office for a soil test, or order a product like the MySoil test kit, which checks your soil's pH and concentrations of more than a dozen different nutrients. If it looks like the soil surrounding your lavender would benefit from more calcium or a higher pH, gather eggshells and prepare them for your garden. It's best to amass a few dozen shells, rinse them, and let them dry before processing them further.

You can use eggshells as a fertilizer for your entire herb garden or a calcium supplement specifically for your lavender. Whichever route you plan to take, consider crushing, grinding, or soaking the shells to coax out the calcium. Breaking the shells into smaller pieces helps them decompose faster whether they're worked into the soil by your lavender's roots or tossed in a bin making compost you'll feed to your lavender later. To crush the shells, you can push a rolling pin over them or place them in a bag and stomp on them. Grinding eggshells in a food processor is a popular approach for gardeners who prefer a powdered product. 

If you want the shells to provide a calcium boost as quickly as possible, take them directly to your lavender plants. Need to deter slugs or cutworms from lavender or its neighbors? Sprinkle crushed shells around your lavender plants' bases. The shell pieces' jagged edges will repel these pests. The sprinkling method can also assist with weed suppression while delivering calcium to your lavender. Or, sprinkle crushed shells on the ground near your lavender and then mix most of them into the soil. If you're introducing new lavender specimens to your garden, put crushed shells in their planting holes.

Would you rather avoid pulverizing eggshells? Make a DIY fertilizer tea with them instead. Pour a dozen shells into a gallon of boiling water, turn off the heat after a few minutes, and let the pot sit overnight. Then, remove the shells, toss them in your compost pile, and hydrate your lavender plants with the calcium-rich liquid.