Should i put eggshells in the compost

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Start with a soil test for garden success. Especially if they could replace a garden product that you might have to purchase otherwise — like agricultural lime. In fact, a study presented at the Iowa State University Integrated Crop Management Conference by extension field specialists John Holmes and Paul Kassel found eggshells to be an effective means of reducing soil acidity, on par with agricultural lime, which is mined from limestone.

Though nitrogen, phosphorus, and potassium levels offered by eggshells are relatively low, the takeaway here is that what is usually discarded as waste can be an incredible source of calcium, with value as an amendment used both to feed plants and to neutralize acidic soil.

You may even want to do a soil test to see how much calcium your soil already contains. If your soil is acidic, amending with a source of calcium may be helpful, depending on what you want to grow. But there are cases when acidic soil is preferable, such as for growing blueberries and other ericaceous plants.

The results of your soil test will help guide you in deciding if adding calcium to your soil is a good idea or not. Chakraborty from Dr. Babasaheb Amebedkar University in Maharashtra, India, described their research on using eggshells as a calcium supplement and fertilizer.

Charles C. Mitchell, extension agronomist with the Alabama Cooperative Extension also studied adding this food waste to the soil in a farm setting to neutralize soil acidity. He determined that adding crushed eggshells to the soil was useless — unless they were ground to a fine powder, smaller than sand. When ground in this way, he found that this powder was even more effective than agricultural lime, providing a source of calcium that was readily available to plants.

In short, large pieces of shell break down too slowly to serve as an amendment or soil sweetener. In addition to preventing blossom-end rot in tomatoes, the calcium in ground shells can be used to prevent apple cork spot , or as an alternative to amending your lawn with lime.

But before you start sprinkling calcium willy-nilly throughout your garden, you may want to learn more about how plants use nutrients and minerals, so that your use of this soil amendment is well-informed. Food waste takes much longer to break down in landfills than it does in compost piles, as landfills are sealed off, anaerobic environments.

In this case, anaerobic decomposition is stinky and inefficient compared to aerobic decomposition, the type that takes place in a well-maintained compost pile — where aerobic microbes thrive because of the presence of oxygen. Those aerobic microbes transform food waste into nitrogen, phosphorus, and magnesium, making excellent material for growing more food! If you are using an anaerobic composting method at home, such as bokashi — the addition of Lactobacilli bacteria to kick-start the fermentation process — then the shells will break down just fine.

Another motivation for composting your eggshells might be to provide better conditions for earthworms, either in your compost pile, or in your vermiculture bin. Before you add eggshells to your compost pile or worm bin, pulverize the dried shells to ensure that your finished compost is smooth and dirt like, uncluttered by large pieces of shell.

Note that composting whole eggs is generally not advisable, since the smell can attract rodents. Grinding them before adding them to your compost or worm bins will also make it easier for the earthworms to use the material as grit. In the meantime, to learn more about keeping your pile balanced, check out our article on the basics of composting. This seed starting method works best for plants that are small and low growing. Plants that can gain height rapidly, such as tomato seedlings , will quickly outgrow these small containers.

And keep in mind that repeated repotting is not recommended for most transplants, as this can cause undue stress and damage their roots. On the other hand, low growing plants such as thyme , cucamelons, or certain succulents would be good candidates for starting in eggshells. Gently wash out the eggshells with warm, soapy water — or bring them to a boil in hot water to sanitize them. If you are able to successfully clean your eggshells without breaking them, next poke two or three small holes into the bottom of each shell to ensure the seedlings have well-drained soil.

The tip of a metal paper clip works well for this. Another garden use for this type of readily-available food waste is to pile sharp, crushed pieces of shell around the bases of plants as a barrier, to deter certain soft-bodied pests.

Scattering crushed eggshells around your crops may help to repel cutworms , those nasty caterpillars that like to chop the heads off of your delicate little seedlings. Cutworms go for the tender stems of young seedlings, so a common defense against these pests is to block their access by placing collars around seedling stems.

According to T. Martin at the Cochise County Master Gardeners office , crushed eggshells are also an effective deterrent against cutworms when a layer is scattered around the stems of sensitive young seedlings. To read more, you can find this book on Amazon. We used a paper plate as our testing grounds.

Around the inner perimeter of the plate we created a barrier made of crushed eggshells, then placed the slugs in the center of the plate. Next, we watched to see if the sharp shards would keep the slugs in the center of the plate — or if the slugs would venture across anyway. We did the same test with pennies as well, since copper is another supposed slug-repelling home remedy.

These shards slowed the slugs down a bit, but the barrier was not enough of a deterrent to make the slugs turn back or to prevent them from crossing it. Want to know what Gillman does recommend for controlling slugs? You can learn more about repelling slugs in our article. I do have to point out that there are many different species of slugs, and as far as I know, Gillman has not tried his experiment on a wide variety of them — so the eggshell barrier may work better against some species than it does with others.

I know, I know — this has been your burning question all along, right? How can you possibly use eggshells in your garden without subjecting yourself and your family to the risk of salmonella infection?

Part of my method for preparing eggshells for the garden involves baking them in the oven to dry them out before grinding. This practice does a couple of things at once — it dries out the sticky, inner membrane and kills salmonella. You only need one second of moist heat at The oven-drying method will expose your eggshells to temperatures higher than that for longer periods of time, so you should be able to set aside those worries about salmonella.

First, collect your shells and rinse them under a tap to remove any raw egg to avoid attracting flies, or unpleasant smells. Two cups of the solution per plant should be adequate. Apply about every two weeks. Gillman, Eggshells can be valuable to gardeners who need to manage soil calcium levels and are beneficial additions to compost, namely worm bins. Eggshells ground to a fine powder yield the quickest results, while large chunks of eggshells will take at least a year to break down making their stored calcium plant available perhaps the next growing season.

Skip to main content. Using Eggshells in the Garden and Compost. Posted by. Christopher Enroth. March 28, How to Use Your Eggshells The trick is to grind up the eggshells. Mitchell, Coffee grinders work well to crush the eggshells into a fine powder, though you may want to invest in a cheap garage sale coffee grinder for your eggshells.

Gillman, Eggshells can be valuable to gardeners who need to manage soil calcium levels and are beneficial additions to compost, namely worm bins. Thankfully, there is a use for all these eggshells! Now I need to hunt for recipes on what to do with all these hardboiled eggs.