Make an All-Natural Plant Fertilizer With Old Eggshells

Egg carton full of egg shells

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This method uses water and eggshells to yield a cheap, nutrient-rich tea for your houseplants and garden.

Eggshells are no stranger to the gardener – whether they are used to start seedlings or crushed to add nutrients to soil, many a plant-lover puts eggshells to use. But I especially like this method of making an eggshell tea (yum!) to use as an all-natural and inexpensive fertilizer that can be used for houseplants or in the garden. Not only does it give our green friends a good boost of calcium, but it gives eggs one last hurrah before heading to the compost.

Calcium is an essential plant nutrient, and as explained in a paper in the Annals of Botany, a calcium deficiency can lead to all kinds of problems, like: "tipburn" of leafy vegetables; "brown heart" of leafy vegetables or "black heart" of celery; "blossom end rot" of watermelon, pepper and tomato fruit; and "bitter pit" of apples. And nobody wants black hearts and bitter pits in their garden.

And a good point that Emily Weller notes in SFGate, "Unlike synthetic fertilizers, when you use eggshells in your garden, you do not have to worry about going overboard."

How to Make Eggshell Tea Fertilizer

• In a large pot, boil a gallon of water and add 10 to 20 clean eggshells to it.
• Turn off heat.
• Allow the brew to sit overnight, then strain.
• Pour the tea on plant's soil.
• Apply once a week.

Why Use Eggshells?

Eggshell is made almost entirely of calcium carbonate (CaCO3), which is a common form of calcium, and the most common form of calcium found in nature (think seashells, coral reefs and limestone). It is also the cheapest and most widely available form of calcium in supplements. And here we are, just throwing it away! Eggshells contain small amounts of other minerals as well. When Master Gardener Jeff Gillman, author of "The Truth About Garden Remedies," sent a batch of eggshell tea to the lab, the results showed that it contained 4 mg of calcium and potassium, as well as very small amounts of phosphorus, magnesium and sodium, reports Weller.

If the eggshell infusion does not appeal to you, you can also crush the shells into a rough crumb or powder. Wash the shells well and crumble them with your hands or grind with a mortar and pestle, food processor, blender, et cetera. Mix it into the garden soil or potting mix.

Lastly, for the least amount of work, you can sprinkle crushed shells (crushed to confetti size) around the garden – this is rumored to be especially good if you have a slug problem, as they are said to not enjoy the sharp edges.

For more all-natural gardening ideas, see related stories below.

Via Southern Living