Two horticultural professionals took some of the most popular garden myths into the university laboratory to prove or disprove the accuracy of these myths. Dr. Linda Chalker-Scott from Washington State University and Dr. Jeff Gilliam from the University of Minnesota tested these myths under controlled conditions to determine if they really work. The Facts There are two different ways eggshells are introdued to soil. The first is to crush the eggshells and work them into the soil at the base of the plant. The second is to boil the eggshells and use the water on the plants. Both approaches are based on the fact that eggshells contain high amounts of calcium. To test the second theory, an eggshell was boiled in distilled water. Distilled water was used to rule out anything that might be present in tap or rain water. The water was sent to the Analytical Lab at The University of Minnesota for testing.The test showed that the water contained five nutrients. The first was sodium, in very small amount which probably wouldn't help or hurt a plant. Two additional elements present were phosphorus and magnesium. While these are beneficial to plants, the amounts were so low that neither would be benefiecial. The last two were potassium and calcium - 4 mg of each. Both of these are really beneficial to plants, The 4 mg is a relative small number but the test was done with only one eggshell, if you boiled multiple eggshells th amount of phosphorous and magnesium would increase.
Hmmm, I wonder how long they boiled the eggshells? Sent from my SM-J320R4 using Grasscity Forum mobile app
They could boil them until the cows come home and there wouldn't be enough calcium to affect anything. Egg shells are calcium carbonate, the same compound in limestone. If eggshells are pulverized and thrown in a compost pile or added to the soil, they will eventually be broken down by organic acids in root exudates and work in the same way as adding lime to your soil. I raise chickens and turkeys and have an unending supply of egg shells. I run them through a food processor I bought at a yard sale for a couple of bucks, then run them through my worm bin where they will ultimately end up in the garden.
Thanks for the info Chunk, I appreciate it. I feel like an outsider, until I get my worm bin going lol. Sent from my SM-J320R4 using Grasscity Forum mobile app
All in good time guod. It took me a few years to build mine after I went organic, I did have some of the best commercially available vermicompost available to me at NW Redworms beforehand so I always had access to good worm casts.
Kind of hard to argue with facts . I originally thought like you . So I checked and found facts I feel are reputable . Do you have any facts otherwise ? The test was done with only one egg and got 4mg , more eggs would increase that value .
I should qualify my statement and sorry for the misunderstanding. When gardeners use lime in the garden it is for the lime's ability to buffer soil pH. With an egg's CaCO3 content at 94%, the calcium carbonate in eggshells is equal to that of limestone. Limestone works differently than calcium in the soil. With calcium being one of the most important elements to healthy plant growth, the form of Ca needs to taken into consideration. While boiling egg shells may extract a minor amount of calcium it is a lot of work for little return. There are better options for calcium in gypsum or even in vermicompost. Here is a really good paper on the different forms of Ca and the relationships in the soil and in plant health. Understanding Limestone, pH and Calcium
By habit , as I throw the egg shells into my compost bucket in the kitchen, I crush the egg shells in my hand and eventually throw it into my big compost pile, then it sits for a while, then gets put into my "finishing" pile, then eventually gets screened and thrown in the final bin I figure either the worms work it or whatever because my finished product shows no signs of egg shells The starter pile is like a horror movie with the worms, pull back the dirt any where in the pile and its solid worms I can't use the finished product on my indoor grows, I tried it, to many tiny creepy crawlies , a mix of soil gnats and a bunch of other stuff I don't recognize It there a way to get finished compost that's not full of bugs? Sent from my van down by the river