Icon - Arrow LeftAn icon we use to indicate a rightwards action. Icon - Arrow RightAn icon we use to indicate a leftwards action. Icon - External LinkAn icon we use to indicate a button link is external. Icon - MessageThe icon we use to represent an email action. Icon - Down ChevronUsed to indicate a dropdown. Icon - CloseUsed to indicate a close action. Icon - Dropdown ArrowUsed to indicate a dropdown. Icon - Location PinUsed to showcase a location on a map. Icon - Zoom OutUsed to indicate a zoom out action on a map. Icon - Zoom InUsed to indicate a zoom in action on a map. Icon - SearchUsed to indicate a search action. Icon - EmailUsed to indicate an emai action. Icon - FacebookFacebooks brand mark for use in social sharing icons. flipboard Icon - InstagramInstagrams brand mark for use in social sharing icons. Icon - PinterestPinterests brand mark for use in social sharing icons. Icon - TwitterTwitters brand mark for use in social sharing icons. Icon - Check MarkA check mark for checkbox buttons.
You are reading

Gardening 101: How to Use Eggshells in the Garden

Search

Gardening 101: How to Use Eggshells in the Garden

May 28, 2019

Last fall I started collecting eggshells after I read an article on Real Farmacy that touted their usefulness in the garden for everything from fertilizer to organic pest control. This spring I’m using the crushed eggshells in the garden five ways.

Photography by Justine Hand for Gardenista.

All winter long I&#8
Above: All winter long I’ve been saving eggshells by simply rinsing them and placing them in an open container where they could dry out. (No, they do not smell. Everyone who comes to my house and sees them asks me this question.)

When my containers are full, I set the kids to pulverizing them into little bits with wooden spoons, thus compacting the shells so that I can collect more.

Fertilizer

When tilled into the soil, ground eggshells provide your plants with calcium.
Above: When tilled into the soil, ground eggshells provide your plants with calcium.

Though nitrogen, phosphorus, and potassium are most vital for healthy growth, calcium is also essential for building healthy “bones”—the cell walls of a plant. Composed of calcium carbonate, eggshells are an excellent way to introduce this mineral into the soil. To prep the eggshells, grind with a mixer, grinder, or mortar and pestle and till them into the soil. Because it takes several months for eggshells to break down and be absorbed by a plant’s roots, it is recommended that they be tilled into the soil in fall. More shells can be mixed into your soil in the spring.

By the same token, finely crushed shells mixed with other organic matter at the bottom of a hole will help newly planted plants thrive. (Tomatoes especially love calcium.) For an exciting recycled garden cocktail, try mixing your eggshells with coffee grounds, which are rich in nitrogen.

Finally, eggshells will reduce the acidity of your soil and help to aerate it.

Seed Starters

Because they are biodegradable, eggshells make excellent, no-waste seed starters. For this, reserve some of your deeper shell halves. Sterilize the shelves by boiling them or by placing them in a 0°F oven for 30 minutes. (If you put them in a cooling oven after, say, you baked a roast chicken, you can sterilize eggs without using excess energy.)
Above: Because they are biodegradable, eggshells make excellent, no-waste seed starters. For this, reserve some of your deeper shell halves. Sterilize the shelves by boiling them or by placing them in a 200°F oven for 30 minutes. (If you put them in a cooling oven after, say, you baked a roast chicken, you can sterilize eggs without using excess energy.)

Next, with a nail or awl, make a hole in the bottom for drainage. Add soil and seeds according to the packaging. When sprouts appear, plant them—egg and all—right into the soil. See a complete DIY at 17 Apart.

Pest Control

A coating of crushed eggshells in the garden is said to help deter several pests, both large and small. Deer dislike the smell of the albumen and will stay away.
Above: A coating of crushed eggshells in the garden is said to help deter several pests, both large and small. Deer dislike the smell of the albumen and will stay away.

Apparently you can also use egg’s insides to deter deer. See DIY: Homemade Deer Spray. Be aware, however, that while deer hate the smell of eggs, rodents love it. Therefore, it may not be best to use this deterrent near the house.

Many gardeners also tout the use of crushed eggshells as a snail and slug repellent. But a recent test by All About Slugs in Oregon seems to have dispelled this. If you’ve had any success with eggshells as slug repellent, we’d be curious to know.

Bird Food

Like plants and people, birds also benefit from a bit a calcium in their diet, especially the females who need extra before and after laying their eggs. To make bird food, start by sterilizing the shells by leaving them in a cooling oven after you bake a meal. Then crush them into fine bits and mix with your favorite seed.
Above: Like plants and people, birds also benefit from a bit a calcium in their diet, especially the females who need extra before and after laying their eggs. To make bird food, start by sterilizing the shells by leaving them in a cooling oven after you bake a meal. Then crush them into fine bits and mix with your favorite seed.

Mulch

Like oysters, eggshells used as mulch provide a striking accent in the garden. If you gather enough, you can even apply a layer thick enough to deter weeds.
Above: Like oysters, eggshells used as mulch provide a striking accent in the garden. If you gather enough, you can even apply a layer thick enough to deter weeds.

Looking for more recycled garden how-tos? See our guide to Edible Gardens 101 and more posts:

EXPLORE MORE: Issue 51: Homesteaders, DIY Projects, DIY, Gardening 101, Composting, Recycled, Organic, Soil & Fertilizers, Birds, Eggs, Mulch, Insects, Seeds

Have a Question or Comment About This Post?

Join the conversation

From our network