For humans, coffee and eggs are a breakfast of champions. Not surprisingly, it’s a good meal for your plants as well. But instead of sipping some hot brew and noshing on a ham benny, your garden will enjoy crushed up eggshells and leftover coffee grounds.
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Make Your Own Natural Fertilizer
Fertilizer can be expensive, but it’s cheap and easy to make your own. Plus, you’ll help compost those leftover coffee grounds and eggshells that would normally go in the trash.
Why are they so nutritious? Eggshells are made up of nearly 98 percent calcium. Meanwhile, coffee grounds contain copper, nitrogen, and potassium.
Still, don’t just dump your leftover grounds from your French press in your garden bed. All it takes is a few quick and easy steps to turn this trash into garden treasure.
In fact, the scraps can be used in more than one way. Read on to learn the 7 ways you can give your plants a boost with coffee grounds and eggshells.
1. Crushed Eggshell and Coffee Ground Fertilizer
First things first, you’ll need to collect your eggshells. Use a large open container that can be stored in a warm place, like a windowsill.
As you’re cooking, thoroughly rinse your shells to remove traces of egg and toss them into your container. Once they are dry and you have enough eggshells, crush them into smaller pieces with a blender, mixer, or mortar and pestle.
Mix in a few scoops of coffee grounds and till the crushed eggshells into the soil. It can take several months for eggshells to break down and for the plant to absorb them.
Because of this, it is best to till the eggshells into the soil in the fall. Finely crushed shells, coffee grounds, and other matter in the soil will combine to feed your existing or newly planted crops. Tomatoes, in particular, respond well to the calcium.
2. Coffee Ground Fertilizer
Coffee grounds are rich in nitrogen, a nutrient plants need. A common argument against using coffee grounds as fertilizer is that they are too acidic. However, coffee grounds are close to neutral, which makes them ideal for plants.
What you don’t want to do is dump your container of used coffee grounds directly onto your plants. You’ll suffocate them!
Instead, you’ll want to first dry out the used coffee grounds by storing them in the oven for a day or so. You don’t need to turn it on, but leave the oven closed to dry them.
Then, you’ll want to gradually work a small amount of coffee grounds into the soil around your plants. You don’t need a lot.
Think 1 tablespoon per potted plant. One cup will suffice for a garden bed. When you’re done, water your plants to release the nitrogen.
You can repeat this weekly, taking note of how your plants respond. Add a little more grounds each week until improvement slows.
3. Eggshell Seed Starters
Eggshells are biodegradable, which makes them great seed starters. Use an empty egg carton to gradually store your more complete shells. You’ll want deeper shell haves, about ⅔ of the shell remaining.
As with the ground fertilizer, you’ll want to thoroughly wash your eggshells as you go. When you’re ready to make the seed starters, sterilize the batch by boiling them or putting them in the oven for 30 minutes at 200 degrees.
Or, place them in a cooling oven once you’re done baking something to save energy. Once the shells are dry, use a nail to carefully create a hole in the bottom of the shell for drainage.
Add soil and seeds according to the package directions. Once you see sprouts, you can plant the starters right into your garden. No need to remove the shell!
4. Eggshell Mulch
If you’ve ever stayed in an oceanside home, you may have seen oyster shells used as a beautiful garden mulch. Save up enough eggshells, and you can create the same effect.
Follow the same steps to create the eggshell fertilizer. However, you don’t need to pulverize the shells so finely.
You can simply crush them into small pieces with a wooden spoon. (This is a great assignment for kids — tell them to have fun with it!)
Once you gather enough, apply a thick layer over your plants to keep weeds away. The result is both effective and aesthetically pleasing.
5. Eggshell Tea Plant Food
Without enough calcium, plants may not produce proper blooms. This is why many gardeners use lime. Instead, you can DIY your own superfood using eggshells.
As usual, rinse your eggshells after using the egg. Then, store in a large container of water. You can add more shells as you use them.
Either way, you’ll want your “tea” to steep for at least a few days. You can keep it on the counter for up to a few weeks.
Mix equal parts eggshell tea and water. Then, water your plants with the mixture. You can use up to one gallon per plant. Your garden will thank you for the calcium boost.
6. Eggshell Deer Repellent
Is Bambi munching on your crops? Deer hate the smell of albumin so they will steer clear of raw eggs. For this repellent, you won’t want to wash your shells thoroughly.
Instead, crush them a little after use and scatter around the plants the deer have been targeting.
Use this technique with caution. While deer don’t enjoy the raw-egg smell, it may attract rodents. So practice sparingly and only use if your garden isn’t very close to the house.
7. Eggshell Bird Food
What garden doesn’t love beautiful bird visitors? Before and after laying eggs, mamma birds need calcium.
Sterilize your eggshells by boiling them or baking in a 200-degree oven for 10 to 20 minutes — until they are dry but not browned inside.
Crumble and place them in a bird feeder or on the grass surrounding your garden. For a really tasty treat, mix with birdseed.
Serve Your Garden a Healthy Breakfast of Eggshells and Coffee Grounds
Before you toss those used coffee grounds and leftover eggshells, consider making a garden fertilizer instead. Stash used eggshells in an open container as you use them (just make sure you rinse beforehand).
Once you collect enough, you can make a tasty fertilizer, bird feeder, or mulch. Dry out your used coffee grounds and incorporate it into your eggshell fertilizer or use on their own — sparingly! Your garden will thank you.