{"id":1031,"date":"2024-10-30T10:02:29","date_gmt":"2024-10-30T14:02:29","guid":{"rendered":"https:\/\/site.extension.uga.edu\/fultonag\/?p=1031"},"modified":"2024-10-30T10:02:29","modified_gmt":"2024-10-30T14:02:29","slug":"getting-the-most-from-eggshells-in-your-tomato-garden","status":"publish","type":"post","link":"https:\/\/site.extension.uga.edu\/fultonag\/2024\/10\/getting-the-most-from-eggshells-in-your-tomato-garden\/","title":{"rendered":"Getting the Most from Eggshells in Your Tomato Garden"},"content":{"rendered":"\n

by Sarah Lawrence, Fulton County Master Gardener Extension Volunteer<\/em> trainee<\/em><\/p>\n\n\n\n

Most of us hopefully know that our vegetable and herb plants need fertilizer to grow well and make produce and understand that organic matter is somehow involved here, like composting. Since I joined the MGEV program, a lot of friends have been forwarding me different TikTok garden hacks; they’re all interesting and I love checking them out, but I wonder: how effective and helpful are these tips?<\/p>\n\n\n\n

\"tomatoes<\/a><\/figure>\n\n\n\n

Let\u2019s look at tomatoes, for example. According to the MGEV handbook (page 446 in the 2022 edition), tomato plants are medium feeders. They love a bit of extra calcium, and I see a lot of TikTok videos using eggshells in different ways to give them what they need. <\/p>\n\n\n\n

You might ask yourself: does this work? Here\u2019s the scoop on how to make eggshells work harder for your tomatoes.<\/p>\n\n\n\n

Eggshells are packed with calcium\u2014exactly what tomatoes need to avoid issues like blossom end rot<\/a> (BER). But not all the calcium from the shells can be used by your plants right away, and BER isn\u2019t always dependent<\/a> on calcium in the soil. <\/p>\n\n\n\n

It depends a lot on things like how fine the eggshell powder is and whether your soil is more acidic (like vinegar) or basic (like baking soda). Tomatoes love a typical pH range of 6 to 6.5, which has an impact on how well they can take up the calcium you give them.<\/p>\n\n\n\n

First of all, simply throwing some eggshells in the garden bed won\u2019t yield results very quickly. Have you ever turned a compost pile? I\u2019ve noticed that even a year later, my whole eggshells are still bopping around in there. Organic matter needs surface area to decompose faster (think about smaller ice cubes melting faster than big ones), so the smaller you crush those eggshells, the faster they\u2019ll decompose and the quicker your plants can grab the calcium out of them. The calcium in the eggshells won’t be available until the shells fully break down, so the more you help that along, the better it\u2019ll be.<\/p>\n\n\n\n

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Tip 1: Got a Blender?<\/h2>\n\n\n\n

Toss your eggshells into the blender and blitz them into dust. This makes it easier for the soil to absorb them and get that calcium out to your plants. (I also like to throw my banana peels in the blender before I dump them in the compost. My partner loves this.)<\/p>\n\n\n\n

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Tomatoes prefer slightly acidic soil. It helps break down the eggshells faster, making the calcium ready to use. If your soil is on the alkaline side (more like baking soda), the eggshells won\u2019t break down as fast.<\/p>\n\n\n\n

The UGA Extension office<\/a> offers soil testing that is affordable and effective. The tests are more sensitive and give personalized recommendations. There are some cheap gadgets that take quick checks of pH, moisture, and light, but if you\u2019re checking for calcium you might as well check for pH too.

For growing tomatoes, you want soil that leans towards the acidic side. If it\u2019s not, you might want to tweak it a bit to get the best out of your eggshells. Your Extension soil test will give you advice on how to do this.<\/p>\n\n\n\n

More info: What is pH in Soils and Why Should You Care About it?<\/a><\/p>\n\n\n\n

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Tip 2: Timing Matters<\/h2>\n\n\n\n

If you want to throw eggshells in your garden, the best times to do this are when you’re planting your tomatoes and during their big growth spurts. They need lots of calcium when they\u2019re flowering and making fruit. Throw a handful of eggshell powder in the hole when you\u2019re planting your tomatoes. <\/p>\n\n\n\n

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If you’re into composting, adding eggshells to your pile is a great move. They break down over time and mix with other compost to create a nutrient-rich superfood for your plants. Do you use worm composting? Ground eggshells can help add grit to a vermiculture<\/a> bin.<\/p>\n\n\n\n

Ultimately, throwing crushed eggshells in your garden may not be immediately helpful, but it doesn\u2019t really hurt anything. <\/p>\n\n\n\n

I like to rinse my eggshells and set them on a shelf to dry in the kitchen, and when I have a bunch gathered I\u2019ll toss them on a baking sheet and bake them for about 15 minutes on a low oven temp, like 200, to make sure they are truly bone-dry. Then, I\u2019ll shove them all in a giant mason jar I\u2019ve been keeping for this purpose! When it\u2019s full around springtime, I\u2019ll throw them in the blender and sprinkle that powder around when I plant tomatoes. <\/p>\n\n\n\n

Okay, but, what is the BEST way to get more calcium into your garden? <\/strong>A lot of us love to look at fun hacks on the internet, but I\u2019m never quite sure which is good advice and which is a waste of time. I decided to put 3 of these methods to the test: crumbled eggshells, ground eggshells, and eggshell tea.  <\/p>\n\n\n\n

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The author’s experimental setup, adding a different eggshell treatment to each pot. Image courtesy of the author.<\/figcaption><\/figure>\n\n\n\n

I rustled up a very old, very neglected plant pot that something had died in a long time ago (and I never emptied; we all have one of those). I figured I would use the most depleted soil I had on hand. <\/p>\n\n\n\n

I ground up eggshells into a fine powder, made an eggshell tea, and roughly crumbled eggshells (about \u00bc cup of eggshell matter per addition), and mixed each one into the depleted soil, leaving a fourth as a control. After ~2 weeks, I took samples of all of the soil to the UGA Extension office to get an official soil sample.<\/p>\n\n\n\n

Method<\/strong><\/td>Phosphorous (lb\/acre)<\/td>Potassium (lb\/acre)<\/td>Calcium (lb\/acre)<\/td><\/tr>
Control<\/td>94<\/td>119<\/td>3996<\/td><\/tr>
Eggshell Tea<\/td>92<\/td>157<\/td>4890 (+884<\/em><\/strong>)<\/td><\/tr>
Crumbled<\/td>121<\/td>128<\/td>6123 (+2127<\/em><\/strong>)<\/td><\/tr>
Ground<\/td>93<\/td>63<\/td>11270 (+7274<\/em><\/strong>)<\/td><\/tr><\/tbody><\/table>
Soil test results after adding eggshell tea, crumbled eggshells, and ground eggshells to potting mix.<\/figcaption><\/figure>\n\n\n\n

All methods boosted the calcium in the soil substantially. I included a few other values from the soil test to show that calcium was the standout change from soil to soil (a little variation is to be expected).<\/p>\n\n\n\n

Experimental Results<\/h2>\n\n\n\n