While eggshells are compostable and can be added to your kitchen countertop bin or backyard compost pile, using eggshells for plants is also beneficial. They provide important minerals—namely calcium carbonate, potassium, and phosphorus—that can be absorbed by your plant's roots after breaking down.
Which plants shouldn't you try this with? Don't add eggshell fertilizer to plants that prefer acidic soil, like blueberries. Ericaceous plants such as mountain laurel, pieris and azaleas also fall into that category. In extreme cases, low acidity for plants could impact their overall health and/or the resulting crop.
You can simply add crushed eggshells in or on the soil as a natural way of providing your indoor plants with extra calcium. Another advantage is that the eggshells will also help to aerate the soil. Airy soil makes it easier for your plant's roots to grow.
Eggshells are rich in calcium, and this makes them a common ingredient of commercial organic fertilizers. But there's no need to pay for the nutrients these products could bring to your soil. Simply crumble the empty eggshells roughly, then scatter them over your flower and vegetable beds.
Crush the eggshells into a fine powder using a mortar and pestle, rolling pin, or food processor. Be sure to wear a mask while crushing the shells to avoid breathing in any eggshell dust. Stir the eggshell powder into your flower bed, indoor plant's potting mix, or vegetable garden's soil.
It's not required to wash eggshells before tossing them into your compost, but some gardeners do for a couple of reasons. Firstly, it removes any of the excess egg off them, which could attract pests or rodents (If you're using a Subpod, this becomes less of a worry).
If you don't want to make the water mixture because that seems like too much work or you simply don't have the time, you could always collect your eggshells, clean them, and crush them directly onto the soil in your garden or into a fine powder to get similar results.
Eggshells take a lot longer to break down compared to many other compostable goods, and too many of them can increase the acidity of your compost. This shouldn't be a problem, unless you plan on using it to grow plants that prefer low soil pH.
In most cases, the grounds are too acidic to be used directly on soil, even for acid-loving plants like blueberries, azaleas and hollies. Coffee grounds inhibit the growth of some plants, including geranium, asparagus fern, Chinese mustard and Italian ryegrass.
Just as when putting egg shells in planting holes, the more finely ground the powder, the faster the nutrients will leach down to the roots. For topical use, a good rule of thumb is to use about a tablespoon or two of pulverized egg shells per plant.
Slugs, snails, and cutworms can do severe damage to your garden. Protect your plants from these pests by spreading coarsely crushed eggshells around your garden. The jagged edges work much like Diatomaceous earth by cutting and then dehydrating these common garden pests.
Because eggshells are so versatile, you can use them as pest control as well as nutrition for your plants, be it for growing tomatoes or making compost.
Epsom salt can improve the blooms of flowering and green shrubs, especially evergreens, azaleas and rhododendrons. Work in one tablespoon of Ultra Epsom Salt per nine square feet of bush into the soil, over the root zone, which allows the shrubs to absorb the nutritional benefits.
Epsom Salt for Plants
Aside from the anecdotal evidence about human benefits, Epsom salt does seem to help plants. Generations of gardeners have said it helps their plants grow bushier, produce more flowers and have better color. It's also said to help seeds germinate and repel slugs and other garden pests.
Banana peels contain: calcium, which promotes root growth helps add oxygen to your soil. magnesium, which assists with photosynthesis. sulphur, which helps plants develop strong roots and repel pests.
Combine the two together, crush the eggshells by hand even more (which should be easier now that they're fully dry), and sprinkle the mixture across the soil bed. Repeat the process every several months or at the start of a fresh growing season. The important thing is to not overdo it.
The shells will decompose quickly and naturally, and when they do they'll add lots of calcium to your pile. It's a common misconception that you can't put eggshells in compost piles because the shell is too hard, but this is far from the truth.
Composting tea bags with existing coffee grounds is easy. Simply add the compostable tea and tea bag components to your pile. There are no other actions you'll have to take, as the worms that break down coffee compost will also break down the tea leaves and other materials.
The key to getting the eggshells to break down in your compost quickly is to give the bacteria as much surface area as possible to work on. While you could do a decent job of crushing them with a rolling pin, I turn my eggshells into a calcium powder.
More importantly, eggshells do attract rats. Eggshells, especially if they are not rinsed, have egg residue on them, which dries and can smell. The smell of eggs is a sure fire way to invite rats to your compost bin as if you were throwing a party specifically for rodents to attend.
Eggshells are biodegradable. As they decompose, they will release nutrients and calcium into the soil, which will help the young plant grow.