33 Natural and Homemade Fertilizers for Plants

Natural fertilizers are a simple and eco-friendly way to nourish your plants. They also improve the health of your soil.

Unlike many synthetic fertilizers, natural fertilizers release nutrients slowly and help build healthier soil over time [1]. They also support beneficial soil organisms and often use materials you already have at home.

Whether you’re growing vegetables, flowers, herbs, or houseplants, there are plenty of affordable ways to provide the nutrients your plants need.

Below are some of the best natural and homemade fertilizers that can help your garden thrive without relying on harsh chemicals.

What is the best natural fertilizer for plants?

Compost is often seen as the best all-purpose natural fertilizer. It improves soil structure, supports beneficial microbes, and provides a balanced supply of nutrients for most plants.

How to Choose the Right Natural Fertilizer

• For leafy growth, choose nitrogen-rich fertilizers such as manure, feather meal, or soybean meal.
• For flowers and fruits, use potassium-rich options such as comfrey fertilizer, seaweed, or banana peels.
• For root development, choose phosphorus-rich fertilizers such as bone meal or fish bone meal.
• For overall soil improvement, compost and worm castings are excellent choices.

A simple soil test can reveal nutrient deficiencies and help you select the most effective fertilizer for your garden.

Quick Natural Fertilizer Guide

Continue reading for detailed information on how to use each natural fertilizer, its benefits, and the plants that respond best to it.

Best Natural Fertilizers for Vegetable Gardens

Below are some options that you can try. However, not every natural fertilizer is suitable for every garden.

Testing your soil first can help you make major adjustments to nutrients or pH. This way, you can choose the most effective fertilizer for your plants.

1. Manure

Most manure used on a farm comes from the feces and urine of animals [2].

Animal manure comes from animals such as cows, rabbits, chickens, sheep, and horses. These are excellent organic fertilizers for vegetable gardens.

Farmers mainly use cow manure on tomato plants because it provides balanced organic fertilization. Poultry manure is also excellent for squash, cucumbers, peppers, and leafy greens.

However, always use aged manure, as fresh manure can burn plants.

2. Earthworm Castings

Earthworm castings contain a variety of essential nutrients that help support healthy plant growth.

They are also mild, so you can use them on flowers, cannabis, vegetables, houseplants, seedlings, and more.

3. Kelp

Kelp meal contains small amounts of nitrogen, phosphorus, and potassium. It also has dozens of trace minerals that support healthy plant growth.

It can help improve plant health and support vigorous growth.

4. Organic Mulch

Mulch is any material placed on the soil surface to cover it and protect it from erosion. Organic mulch adds nutrients to the soil.

Spread sawdust, shredded leaves, pine needles, or grass clippings over the soil surface. Allow them to break down naturally over time.

Organic mulches also help retain soil moisture.

5. Compost

Compost is an excellent soil amendment for vegetable gardens. It is made of kitchen scraps, such as vegetable peels, fruit rinds, grass trimmings, coffee grounds, and other organic materials.

Compost is very versatile for the garden. You can use it as an organic soil conditioner for your garden or make compost tea.

6. Shell Meal

Shellfish meal is made from the crushed shells of crabs, shrimp, or lobsters. It contains calcium along with smaller amounts of phosphorus, nitrogen, and potassium.

7. Bat Guano

Bat guano contains nitrogen, phosphorus, and potassium.

This organic fertilizer is great for seedlings. It also benefits lawns, houseplants, flowers, and ornamentals.

You can use it at any time of the year as a topdressing.

Moreover, you can dilute it and make a ‘tea’ for a foliar spray. However, use it carefully and according to the package instructions.

8. Fish Bone Meal

Fishbone meal is made from dehydrated fish bones containing phosphorus, calcium, and a little nitrogen. It is especially useful for flowering plants, bulbs, and fruiting crops.

9. Eggshells

You can also crush calcium-rich eggshells and add them to your homemade fertilizer mix. They will provide nutrients and improve soil structure.

To make your eggshell fertilizer, rinse and dry the eggshells thoroughly. Next, crush them into tiny bits or grind them into a fine powder using a blender.

Finally, sprinkle the powder around the base of your plants or mix it into the soil. Tomatoes, eggplants, and peppers will enjoy this treat.

10. Vinegar

Some acid-loving plants, such as azaleas, rhododendrons, gardenias, and certain hydrangeas, may benefit from occasional pH adjustments.

Mix one cup of household vinegar with a gallon of water to water these plants. You can do this once every three months.

A low pH can harm plants that prefer neutral or alkaline soil conditions. Always test your soil before altering its pH.

11. Epsom Salt

Epsom salt contains magnesium, which is an essential nutrient for plant growth.

It may benefit plants if your soil is magnesium-deficient. However, it should not be used routinely unless a soil test indicates a deficiency.

To replace depleted magnesium levels in the soil, use two tablespoons dissolved in one gallon of water.

12. Bone Meal

As the name implies, bone meal is finely ground bone from slaughterhouses. It is a fantastic source of calcium and phosphorus.

Bone meal fertilizer can be used for bulbs, flowers, and fruiting trees. It helps establish a strong root system.

13. Rock Phosphate

Rock phosphate contains generous amounts of calcium and phosphorus. It works well on vegetables, flowers, trees, and shrubs.

14. Greensand

Greensand is a popular type of mineral from the seabed.

It is rich in glauconite, which contains minerals such as potassium, magnesium, and iron. All these nutrients are good for plants.

15. Alfalfa Meal

Alfalfa meal is usually a significant part of livestock diets. However, grinding it up results in a fertilizer mixture containing the three key macronutrients (NPK).

It also contains other nutrients.

16. Cottonseed Meal

Cottonseed meal contains nitrogen, phosphorus, potash, and other plant food elements. It is excellent for conditioning the soil and improving its structure.

17. Soybean Meal

As a slow-release fertilizer, soybean meal releases a good amount of nitrogen and potassium into the soil as it breaks down.

18. Feather Meal

Feather meal is another slow-release nitrogen fertilizer. For best results, apply it to the soil well in advance. It works well on tomatoes and corn.

19. Seabird Guano

This unique fertilizer is sourced from islands home to seabirds. Seabird guano is suitable for most indoor and outdoor flowering plants.

Strawberries, melons, and other plants with large blooms love seabird guano.

20. Seaweed

Seaweed fertilizer contains potassium, zinc, iron, and small amounts of other nutrients. It is an excellent crop fertilizer.

Flowering plants that like seaweed fertilizer include geraniums, camellias, roses, and gardenias.

21. Grass Clippings

You can get grass clippings for free if you own and use a lawn mower. However, avoid using cuttings from herbicide-treated lawns.

Grass clippings contain some nitrogen, potassium, and phosphorus.

To use grass clippings as fertilizer, place them in a bucket of water and allow them to steep for a few days. Afterward, strain the solution and use it to water your plants.

Only use untreated grass clippings that have not been sprayed with herbicides or pesticides.

22. Ag Lime

Agricultural lime adds calcium and magnesium to the soil. It also improves soil pH and neutralizes its acidity.

Plants that benefit from lime include peas, spinach, parsnips, onions, and apple trees. Be sure to test your soil before using it.

23. Wood Ash

Ashes from the fire pit can be used as an excellent organic soil amendment.

Plants that benefit from wood ashes include lettuce, parsnips, garlic, chives, carrots, and asparagus. Wood ash also helps keep pests like slugs, snails, and ants away.

However, avoid using wood ash around acid-loving plants such as blueberries, azaleas, and rhododendrons because it raises soil pH.

24. Coffee Grounds

Used coffee grounds improve soil structure and add organic matter.

To make a homemade nitrogen fertilizer for plants, add 2 cups of coffee grounds to 5 gallons of water and let it sit overnight. Afterward, strain the liquid and spray the plant leaves with it.

However, while coffee-ground tea may provide small amounts of nutrients, adding used coffee grounds directly to compost is generally more effective.

25. Green Tea Leaves

When added to the soil, green tea leaves can benefit a plant’s overall health. Just sprinkle them over the soil around your plants.

Alternatively, you can make a DIY liquid fertilizer by soaking a few used green tea bags in water for 24 hours. Afterward, you can use it to water your plant beds and houseplants.

Plants that like tea leaves include berry bushes, ferns, African violets, jade plants, and hydrangeas.

26. Molasses

People have been using molasses in gardening practices for years. However, different types of molasses vary in nutrient content.

Blackstrap molasses has high levels of sulfur, magnesium, iron, calcium, and potassium. This mix gives plants a substantial boost when applied.

To make homemade plant fertilizer, mix one to two tablespoons of unsulfured blackstrap molasses into a gallon of water. Spray the mixture on plant leaves or pour it around the plant’s roots.

You can also add unsulfured blackstrap molasses to fertilizer mixes.

27. Urine

You read that right! It has been shown that urine from a healthy person can be used as a highly clean and beneficial agricultural fertilizer [3].

Urine is about 95% water and contains nitrogen, potassium, and phosphorus. These nutrients are highly beneficial to plants.

Urine should be diluted before application, typically at a ratio of about 10 parts water to 1 part urine. Avoid using urine from individuals taking certain medications or if local regulations prohibit its use.

If you’re a little squeamish, it’s okay; plenty of other healthy plant fertilizer options are on this list.

28. Gypsum

Gypsum is an excellent source of calcium and sulfur. Both are essential for improving crop yields and plant growth.

Gypsum can also help reduce topsoil erosion.

29. Azomite

Azomite is a natural mineral mined from volcanic deposits in Utah, USA. It contains dozens of trace minerals that may help support healthy plant growth and improve soil fertility.

30. Banana Peels

Banana peels provide potassium and small amounts of other nutrients. However, they should be seen as a supplemental fertilizer, not a complete plant food.

To make liquid banana-peel fertilizer, cut the peels into small pieces and place them in a container. Next, cover the peels with water and let them steep for a few days.

Finally, strain your banana peel tea and dilute it with five parts of water before using it to water your plants.

31. Comfrey Fertilizer

Comfrey is one of the most valuable plants for making homemade fertilizer.

Its deep roots pull nutrients from the soil, especially potassium. This nutrient effectively supports flowering and fruiting plants.

To make comfrey fertilizer, fill a bucket with chopped comfrey leaves, cover them with water, and allow them to steep for several weeks. Dilute the liquid before using it on tomatoes, peppers, cucumbers, and other fruiting crops.

32. Weed Tea Fertilizer

Many common garden weeds contain valuable nutrients that can be returned to the soil. Dandelions, chickweed, nettles, and clover are often used to make weed tea fertilizer.

Simply place freshly pulled weeds in a bucket, cover them with water, and let them soak for one to two weeks. Strain the liquid and dilute it before applying it around your plants.

However, avoid using weeds that have gone to seed or invasive weeds that may spread.

33. Aquarium Water

Old aquarium water can be an excellent fertilizer for plants.

Fish waste naturally contains nitrogen and small amounts of other nutrients. These nutrients can support healthy plant growth [4].

Instead of pouring used aquarium water down the drain, use it to water your garden, houseplants, or container plants. However, avoid using water from saltwater aquariums, as the salt can damage plants.

Frequently Asked Questions

What is the best homemade fertilizer for vegetables?

Compost is one of the best homemade fertilizers because it provides a wide range of nutrients and improves soil structure.

Can you use too much natural fertilizer?

Yes. Applying too much fertilizer, even natural ones, can damage plants and lead to nutrient imbalances.

Which natural fertilizer contains the most nitrogen?

Feather meal, poultry manure, soybean meal, and urine are among the richest natural sources of nitrogen.

How often should homemade fertilizer be applied?

Most homemade liquid fertilizers can be applied every two to four weeks during the growing season.

Are homemade fertilizers safe for houseplants?

Yes, many are safe for houseplants when used in moderation and properly diluted.

What is the fastest-acting natural fertilizer?

Diluted fish-based fertilizers, compost tea, and properly diluted urine are among the fastest-acting natural fertilizers.

Do natural fertilizers improve soil health?

Yes. Natural fertilizers add organic matter, which improves soil structure and water retention. They also boost beneficial microbial activity in the soil.

Can I mix different natural fertilizers together?

Yes, but avoid overapplying nutrients. Combining compost with materials such as worm castings or kelp meal is often beneficial.

Takeaway          

Healthy plants don’t always need expensive store-bought products to thrive.

Many of the best fertilizers can be made right at home using simple, natural ingredients. These homemade fertilizers nourish the soil and support strong plant growth.

By choosing natural options, you can reduce chemical exposure in your home and garden. This decision also allows you to recycle household waste and create a more sustainable garden.

Whether you use compost, manure, worm castings, seaweed, or homemade fertilizer teas, selecting the right fertilizer for your soil and plants can help you enjoy healthier harvests and more productive gardens.