Sustainable Gardening: How to Use Eggshells to Make Plants Bloom
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Instead of using chemically-synthesized fertilizers from the garden store, smart gardeners opt for natural and ecologically valuable alternatives that they already have at home. A sustainable fertilizer can often be found on every breakfast table and can go straight to the garden: eggshells.
The Benefits of Eggshells for Plant Growth
Eggshells contain a lot of calcium carbonate, also known as lime, and they also provide numerous other micronutrients that plants need for healthy growth. Because of their high calcium content, eggshells are an ideal source of nutrients for plants that thrive in alkaline soil.
This includes beans, peas, tomatoes, beets, chard, carrots, and herbs like thyme, sage, and lavender. Most fruit trees and shrubs, such as maple, linden, and ornamental cherry trees, also appreciate an additional supply of calcium.
Not Suitable for Acid-Loving Plants
However, plants that prefer acidic soil should not be fertilized with eggshells. Due to their high calcium content, the shells raise or neutralize the pH level of the soil. Plants like hydrangeas, anemones, begonias, heathers, lilies, lupines, magnolias, lilies of the valley, peonies, phlox, rhododendrons, and pansies fall into this category.
Using Crushed Eggshells for Fertilization
To provide plants with calcium, the eggshells should be crushed into the smallest possible pieces. If you want to be thorough, you can use a mortar to help. The smaller and finer the eggshells, the more easily the calcium will be incorporated into the soil cycle, and the sooner the fertilized plants can benefit from it.
Tip: The thin membrane that sticks to the shell should be removed before crushing the eggshells, if possible. It tends to become slimy and makes it more difficult to powderize the shells.
Application Methods
The crushed eggshells can be placed directly in the garden bed or on the soil in plant containers. If the shells have been powdered, they can also be added to the watering can. To do this, let the shells soak in water for about twelve hours (rule of thumb: 2 eggs per liter of water) to allow the mineral content to dissolve. Then pour the liquid through a fine sieve into a watering can and water the root area of the plants.
It's important to note that over-fertilizing can harm plants, and fertilization is not always necessary. If you live in an area with particularly hard water, you may not need additional fertilization. To determine the condition of the soil and watering water, you can use pH test strips available at construction and garden stores as well as pharmacies.
