hi. in today’s two minute tip, i’ll show you how we use eggshells to improve soil fertility. eggshells contain a number of minerals that are essential to plant growth, most notably calcium, which plays an important role in the strength and thickness of plant cell walls. sufficient calcium in the soil also helps prevent blossom end rot, which i’ll discuss later. researchers in the netherlands studying the mineral composition of chicken eggs found that powdered eggshells were, on average, 39.15% calcium,
0.4% nitrogen, and 0.38% magnesium. all of these nutrients are essential to plant health. before using eggshells in our garden, we rinse them and microwave them for 2 minutes to kill possible pathogens like salmonella. after collecting eggshells for a few weeks, we grind them into a powder using our vitamix. other high powered blenders would also do the trick, as would a coffee grinder. the calcium in eggshells is in the form of calcium carbonate,
which is not plant available. so, we don’t use eggshells as a quick fix for calcium deficiencies, but instead as a slow release of calcium and other minerals. for a quick fix, you could create soluble calcium from eggshells using an acid like vinegar, but we’ve never found it necessary. we incorporate our eggshells into our worm bins and compost piles, and rely on the microbes and earthworms to break down the calcium and make it plant available over time. of course, grinding the shells into a powder speeds up this process significantly.
the fine eggshell particles are small enough for worms to ingest, and provide a source of grit that aids in the worms’ digestion. in addition, a sufficient supply of calcium is critical to worm health and reproduction, which leads to more nutrient-rich castings for the garden. finally, blossom end rot is not usually caused by a calcium deficiency in the soil, but instead by a plant’s inability to effectively move water, and therefore calcium, throughout the plant body. that said,
adding eggshells to your garden will reduce the likelihood that an actual calcium deficiency in the soil is responsible for blossom end rot. well, that's all for now. thank you very much for watching this two minute tip.