From the Kitchen to the Garden: 10 Ways to Use Leftovers as Natural Fertilizers

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Table of Contents

Table of Contents


Do you ever find yourself with kitchen leftovers that you’re not quite sure what to do with? Instead of discarding them, you can put them to good use by repurposing them as natural fertilizers for your plants. Using kitchen leftovers to supplement your garden soil can help reduce food waste while improving soil quality, increasing plant growth, and reducing the need for synthetic fertilizers. Here are ten examples of kitchen leftovers that can benefit your plants:

1) Coffee Grounds

Used coffee grounds are a rich source of organic matter that contain valuable nutrients, such as nitrogen, phosphorus, and potassium, which are essential for plant growth. The high carbon-to-nitrogen ratio of coffee grounds can improve soil structure, water-holding capacity, and aeration. Additionally, coffee grounds can stimulate the growth of beneficial soil microbes that can suppress soil-borne pathogens.

2) Eggshells

Eggshells are an excellent source of calcium, a macronutrient that plays a crucial role in plant cell wall formation, nutrient uptake, and enzyme activation. Calcium deficiencies in plants can lead to stunted growth, leaf curling, and fruit deformation. Eggshells can be crushed into small pieces and added to the soil to improve calcium availability.

3) Banana peels

Banana peels are rich in potassium, another macronutrient that is vital for plant growth, especially during flowering and fruiting stages. Potassium helps regulate water balance, strengthen cell walls, and enhance stress tolerance. Banana peels can be cut into small pieces and buried in the soil to slowly release potassium.

4) Vegetable scraps

Vegetable scraps are a valuable source of organic matter and nutrients that can be converted into nutrient-rich compost, which can improve soil fertility and structure. Vegetable scraps contain a range of macronutrients, micronutrients, and trace elements that are important for plant growth, such as nitrogen, phosphorus, potassium, magnesium, calcium, iron, and manganese.

5) Tea leaves

Used tea leaves contain a variety of nutrients, including nitrogen, phosphorus, potassium, and trace elements, that can enhance plant growth and health. Tea leaves can also boost soil organic matter content and improve soil microbial activity, which can promote nutrient cycling and disease suppression.

6) Citrus peels

Citrus peels contain essential oils, flavonoids, and terpenes that have antifungal, antibacterial, and insecticidal properties. Citrus peels can be chopped into small pieces and added to the compost pile to accelerate decomposition and add valuable nutrients to the soil.

7) Fish tank water

Fish tank water is a rich source of nitrogen, phosphorus, and other nutrients that can benefit plants. However, fish tank water should be diluted before use to avoid over-fertilizing and causing harm to plants.

8) Cooked rice

Cooked rice can be used as a soil amendment to increase soil organic matter content, improve soil structure, and enhance water-holding capacity. Rice can also serve as a source of energy for beneficial soil microorganisms.

9) Stale bread

Stale bread can be repurposed as a bread crumb mulch that can improve soil moisture retention and reduce weed growth. Bread crumbs can also provide a source of carbon for soil microorganisms, which can help break down organic matter and release nutrients.

10) Leftover pasta water

Pasta water contains starch, which can improve soil water-holding capacity and provide a source of energy for soil microorganisms. Pasta water can be cooled and used to water plants as a natural fertilizer.


Using kitchen leftovers as natural fertilizers can benefit your plants and the environment by reducing food waste and chemical fertilizer use. However, it’s important to use these items in moderation and in conjunction with a balanced fertilization program. Too much of a good thing can be harmful to your plants, so be sure to use kitchen leftovers in moderation.

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