Kitchen scraps: for the Garden A good breakfast for us may be eggs, orange juice, a banana, and a hot cup of coffee or tea. Believe it or not, this is also a good meal for your plants. It will not only help them grow stronger, but discourages pests. The same nutrients that make these foods healthful for humans make them beneficial for plants: calcium, potassium, and nitrogen, assorted vitamins and minerals, with bits of protein.
While all of these items can be used as compost material, there are easier, and more immediate, uses in your garden or houseplants.
By Ellen Rubin
Kitchen Scraps to Feed Your Plants
Banana peels are rich in potassium (also known as potash). Plants need potassium to improve the rigidity of their stems, process existing water supplies, enhance fruit and vegetable production, and increase their disease resistance. This is especially important during times of drought or to survive the winter. It is one of the three major nutrients plants receive from the soil or fertilizer (and the third number you see on fertilizer packages). Luckily, there are no negative effects if your plants overindulge on potassium. So…why buy fertilizer when you have leftover banana peel?
There are several way to use them:
- Dice or shred the peel, let it dry out, then scatter it on top of the soil. It will eventually rot and the nutrients will soak into the soil.
- Bury small pieces of peels 1-2” deep in your garden. This will not only add nutrients, but also repel aphids and ants. They don’t like the smell.
- The entire peel can be buried more deeply near the plant’s roots. Unfortunately, this has the potential of attracting animals who might want to dig it up.
- A banana tea can be made by soaking a fresh peel in water for a day or two, then use it to water your plants. This gives them a quick boost of potassium.
- You can make a yellow-jacket trap by adding a banana peel to water, sugar, and apple cider vinegar.
Eggshells are a great source of nutrients because they are rich in calcium. In fact, 95-98% of the shell is made of calcium carbonate. The remainder is magnesium, potassium, iron, phosphorus, protein, and trace amounts of manganese.
You can actually purchase eggshell powder, but why bother when it is easy enough to make. Merely wash your eggshells and crush them in a bag. You can also create a fine powder by using a blender.
In addition to providing nutrients, eggshells act as a pest deterrent to slugs and snails. Make a 2” ring around the plant about ¼” deep. The sharp edges will keep the soft bodied pests away.
Many people like to use the eggshell as a starter pot for seedlings. Merely cut or carefully crack only the top portion of the egg off and wash out the shell. The entire pot can be planted when the time is right.
If you have started seedlings in a different way, when you plant them in your garden or re-pot for your house, work some of the powder into the soil. It can also be worked into the soil around your established plants at any time to give them a boost of nutrients. You can add the shells of 4-5 eggs per plant. It is especially useful in staving off blossom-end rot in tomatoes.
Finally, eggshells are a great source of nutrients for birds. It is especially necessary for females who become drained of calcium by laying eggs. You need to take the added step of sterilizing the shells, but this is easily done in either your microwave or stove. Merely wash and lightly dry the shells and either: microwave them on high for around 2 minutes, place them in a 250-325° oven for 20-30 minutes, or boil the shells for at least 5 minutes in a pan of water. Sterilized shells can be stored in a zip lock bag until you are ready to use them.
Coffee grounds are another beneficial addition to plants, both nutritionally and as a pest deterrent. The most important thing to remember is that the coffee grounds must be used. Fresh grounds are too acidic, but once brewed, they have a neutral pH of around 6.5.
Coffee grounds add nitrogen to your garden soil. (The first number listed on packaged fertilizer.) By volume, they are about 2% nitrogen. Nitrogen is considered the most important mineral in plant growth. It is an essential element of chlorophyll and helps the plant create food. A lack of nitrogen may show up in your plants as a general yellowing (chlorosis) of your leaves, weak and spindly stems, small leaves, and a weak root system. Grounds also contain calcium, copper and potassium. Coffee ground fertilization is especially useful for plants like lettuce, corn, peppers and onions that love nitrogen rich soil.
There are several ways to recycle your used coffee grounds. To repel cats, rabbits and squirrels from digging in your garden use the grounds as mulch. The strong scent is a deterrent. However, a thick coating left on top of the soil can become too smelly for some people. Therefore, most people prefer to work the grounds into the soil around the plants to avoid the smell. Grounds can be used around the base of plants to keep slugs and snails out, much like egg shells. For potted plant use, start with around 1 tablespoon per pot. You can also sprinkle it around your plants right before watering for a gentle, slow-release fertilizing of nitrogen.
If you prefer a quicker feeding method, you can soak the grounds in water overnight to let them dissolve. This solution can be used for watering, or even as a spray for a fast infusion of nitrogen.
If you aren’t a coffee drinker, but would like to try using coffee grounds, many coffee houses, including Starbucks, give away free bags of used coffee grounds.
If you are a tea drinker, your plants can still benefit from your leftovers. Tea contains tannic acid, made up of polyphenolic compounds. These can act as a pest deterrent, soil pH adjuster, and fertilizer. Much like coffee, tea contributes nitrogen to the soil. The tea leaves also provide food for earthworms. The worms not only prevent the soil from becoming compacted by creating pathways and aeration, but their excrement is a nutrient-rich fertilizer.
You can create a mulch of tea bags that help block weeds from growing, and like coffee grounds, bugs and pest animals don’t like the bitter scent, thereby acting as a deterrent. Tea bags are usually made from Manila hemp. While hemp is a strong material, it will easily decompose in your garden or compost heap.
Tea bags have the added bonus of being great at retaining water. They can be used in several ways. You can bury the bag so it acts as a sponge. This is especially useful in arid climates or during a hot summer. They can also be used as a seed-starter medium. Merely sterilize the tea and bags by boiling them in hot water, make a hole in the flat bag, insert a seed, and keep it moist. (A paper towel that is kept dampened underneath will accomplish this.) Once the seed has germinated, the entire seedling/bag can be re-planted.
Tea is slightly acidic. This is helpful if you have hard water (water with a high salt content). It can neutralize your soil by correcting the pH. Certain plants, such as hydrangeas, gardenias, and azaleas like more acidic soil so using tea bags is a safe, natural, non-toxic way to adjust your soil’s pH. Finally, if there are metals, like aluminum in your soil, the tannic acid prevents them from entering the root system, promoting root growth.
Orange Peel or Other Citrus
Nutritionally, orange peels contribute vitamin C, manganese, and a bit of calcium. Their greatest use in the garden is as a pest deterrent. If cats using your yard as a litter box is a problem, scatter some peels around – they don’t like the smell. You can dice them up into smaller pieces and even dry them a bit before you put them around your plants.
Orange peel also repels aphids, ants and mosquitoes. Use shredded or grated peels to eliminate these bugs from your garden.
Finally, much like egg cups, halved orange peels can be used as containers for planting seeds. Once the seedlings are big enough, merely plant the entire cup in your yard.
The wonderful thing about these 5 breakfast foods for your garden is that they would ordinarily end up in the garbage. By recycling them for plant use, you not only decrease what you send to a landfill, you enrich your soil and repel pests – naturally. You improve your garden, avoid chemical additives, increase oxygen levels, and decrease methane emissions (from landfills), all for very little effort and no additional cost.
Quick Reference Guide to Beneficial Kitchen Scraps
|Banana Peel||Eggshell||Coffee Grounds||Tea Bags||Orange Peel|
|Nutrients||Potassium||Calcium (trace magnesium, potassium, iron, phosphorus, protein, manganese)||Nitrogen (trace calcium, copper, potassium)||Tannic Acid (nitrogen)||Vitamin C, manganese, calcium|
|Pest Control||Aphids, ants, small animals||Slugs, snails||Slugs, snails, small animals||Bugs & small animals||Aphids, ants, mosquitoes, Small animals|
|Soak for Watering||yes||yes||Yes|
|Mulch/Weed Control||Yes, but may get smelly||Yes|
4 Kitchen Scraps to Use In the Garden – Even if You Don’t Compost, Lindsay-Jean Hard, Food52.com, May 21, 2015.
6 Kitchen Scraps You Can Use in Your Garden, Trina Krug.
7 Ways to Use Food Scraps in the Garden (They’re Not Just for Compost), Jonathon Engels, OneGreenPlanet.org, 2018.
Can Tea Grounds Help a Plant Grow?, Casandra Maier, SFGate, Updated December 17, 2018. Ways to
Is Tea Good For Plants?, Lahn Ma, eHow.com.
No Compost Required: Instantly Fertilize Plants with These 3 Kitchen Scraps, Nicole Willner, Plant Green.
Use Old Tea Bags In The Garden, Ashley Brewer, HomeHacks.co, March 21, 2018.
Using Kitchen Scraps In The Garden Even If You Don’t Compost, Growing Organic.