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.

Many natural fertilizers release nutrients slowly and help improve soil health over time [1].

However, some, such as fish emulsion and diluted urine, provide nutrients more quickly. Natural fertilizers can also support beneficial soil organisms and may 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.

Some options on this list are fertilizers, while others are soil amendments. Fertilizers mainly provide plant nutrients, while soil amendments improve the condition of the soil.

What is the Best Natural Fertilizer for Plants?

Compost is one of the best all-purpose soil amendments. It improves soil structure and adds small amounts of nutrients that help plants grow.

How to Choose the Right Natural Fertilizer

• For leafy growth, choose nitrogen-rich fertilizers such as manure, feather meal, or soybean meal.
• For flowering and fruiting plants, potassium-containing options include comfrey fertilizer, kelp meal, and seaweed products. Use a soil test to determine whether extra potassium is needed. Banana peels can add small amounts of potassium but work best as a supplement.
• 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 and Soil Amendment Guide

Nitrogen-Rich Fertilizers

These fertilizers encourage leafy growth.

• Manure
• Bat Guano
• Soybean Meal
• Feather Meal
• Grass Clippings
• Urine
• Aquarium Water

Phosphorus-Rich Fertilizers

These fertilizers support root development, flowering, and fruit production.

• Bone Meal
• Fish Bone Meal
• Rock Phosphate
• Seabird Guano

Potassium-Rich Fertilizers

These fertilizers help promote flowering, fruiting, and overall plant health.

• Seaweed
• Kelp Meal
• Banana Peels
• Comfrey Fertilizer
• Wood Ash
• Greensand

Calcium and Magnesium Sources

These materials can provide calcium or magnesium and may improve soil conditions when a deficiency is present.

• Eggshells
• Shell Meal
• Agricultural Lime
• Gypsum
• Epsom Salt

Soil Builders and General-Purpose Options

These options can improve soil structure, add organic matter, or provide a range of nutrients.

• Compost
• Earthworm Castings
• Organic Mulch
• Alfalfa Meal
• Cottonseed Meal
• Coffee Grounds
• Green Tea Leaves
• Molasses
• Weed Tea Fertilizer
• Azomite

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 Plants (Organic and Homemade Options)

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.

Cow manure is a popular organic fertilizer because it provides a balanced mix of nutrients and organic matter. It can be used around many vegetables, including tomatoes.

Poultry manure can provide nutrients for squash, cucumbers, peppers, and leafy greens when properly aged or composted. 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 gentle enough to use on flowers, vegetables, seedlings, and houseplants.

3. Kelp

Kelp meal contains small amounts of nitrogen, phosphorus, potassium, minerals, and natural compounds that may help plants handle stress and grow well.

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. As organic mulch breaks down, it can slowly add organic matter and 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 a valuable 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 or make compost tea, which may add beneficial microbes and small amounts of nutrients.

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. It can help improve soil health and provide nutrients for plants over time.

7. Bat Guano

Bat guano contains nitrogen, phosphorus, and potassium.

It can provide nutrients for seedlings and mature plants when used correctly. Always follow package directions.

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. It contains phosphorus, calcium, and small amounts of 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.

Eggshells slowly add calcium to the soil as they break down. They are best used as part of a long-term soil improvement plan.

10. Pine Needles

Pine needles are a natural mulch that can help improve your garden soil. As they slowly break down, they add organic matter and help the soil hold moisture.

Many gardeners worry that pine needles will make the soil too acidic, but this is usually not true. Old, dry pine needles break down slowly and have little effect on soil pH.

Pine needle mulch works well around acid-loving plants such as blueberries, azaleas, rhododendrons, and some hydrangeas. It can also help keep weeds down and protect plant roots from temperature changes.

To use pine needles, spread a layer around your plants. Avoid piling them too thickly against plant stems, as this can trap too much moisture and encourage rot.

11. Epsom Salt

Epsom salt may help plants if your soil is low in magnesium.

However, it should not be used routinely unless a soil test shows a deficiency. Using too much can upset the nutrient balance in your soil.

If a soil test shows that your soil lacks magnesium, follow the product label for the correct amount to use.

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 can provide phosphorus and calcium, which may support root growth when the soil lacks these nutrients.

13. Rock Phosphate

Rock phosphate contains calcium and phosphorus. It releases nutrients slowly and works best when soil conditions allow plants to absorb phosphorus easily.

14. Greensand

Greensand is a popular type of mineral from the seabed.

It is rich in glauconite and can provide potassium, along with smaller amounts of other minerals. Its nutrient content can vary by product.

15. Alfalfa Meal

Alfalfa meal contains the three key plant macronutrients—nitrogen, phosphorus, and potassium (NPK)—along with 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.

Choose organic cottonseed meal when possible, especially if you are growing food crops.

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 flowering plants may benefit from seabird guano when used correctly.

20. Seaweed

Seaweed fertilizer contains potassium, zinc, iron, and small amounts of other nutrients. It is a useful natural supplement for many crops.

Flowering plants that may benefit from 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.

Keep the bucket covered because grass clipping tea can develop a strong odor. Also, 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 such as peas, spinach, parsnips, onions, and apple trees may benefit from lime when the soil is too acidic. Be sure to test your soil before using it.

23. Wood Ash

Clean wood ashes from a fireplace or fire pit can be used as an organic soil amendment.

Plants that benefit from wood ashes include lettuce, parsnips, garlic, chives, carrots, and asparagus. Wood ash may temporarily deter some pests, but its main benefits are supplying minerals and raising soil pH.

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.

Some gardeners make coffee-ground tea by adding 2 cups of used coffee grounds to 5 gallons of water and letting it sit overnight. However, this provides only small amounts of nutrients.

Avoid adding large amounts of fresh coffee grounds directly to garden soil because they may slow plant growth.

25. Green Tea Leaves

Used green tea leaves can add a small amount of organic matter to the soil. You can add them to your compost pile or sprinkle a small amount around plants after removing the tea bag and any staples.

You can also make a weak tea by soaking used green tea bags in water. However, this should be viewed as a mild supplement rather than a complete fertilizer.

26. Molasses

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

Blackstrap molasses contains sulfur, magnesium, iron, calcium, and potassium. However, the amount of nutrients available to plants can vary.

Molasses may also help support soil microbes, but it should not replace a complete fertilizer.

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! Properly diluted human urine can provide nitrogen and other nutrients for plants when used safely [3].

Urine is about 95% water and contains nitrogen, potassium, and phosphorus. These nutrients can help support healthy plant growth when used properly.

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 using urine in the garden does not appeal to you, there are many other natural fertilizer options available.

Avoid applying urine directly to plant leaves because the concentrated salts may cause damage.

28. Gypsum

Gypsum is a useful source of calcium and sulfur. Both nutrients are important for plant growth, especially when the soil lacks them.

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.

If you choose to make banana peel tea, strain the liquid and dilute it before using it on plants. However, composting banana peels is usually a better way to return nutrients to the soil.

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 a useful 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.

Best Natural Fertilizers by Plant Type

For Tomatoes

• Compost
• Aged manure
• Fish bone meal
• Kelp meal

For Vegetables

• Compost
• Aged manure
• Worm castings
• Fish emulsion
• Kelp meal

Houseplants

• Worm castings
• Compost tea
• Diluted fish fertilizer

For Flowers

• Compost
• Bone meal (if phosphorus is low)
• Comfrey fertilizer

For Lawns

• Compost
• Grass clippings
• Corn gluten meal
• Manure tea

Natural Does Not Always Mean Safe

Natural fertilizers can benefit your garden, but too much of any fertilizer can harm plants.

Always follow recommended amounts. Avoid using fresh manure directly around growing vegetables, salty materials, or strong mixtures directly on 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 can be rich natural sources of nitrogen. The exact amount varies by product and material.

How often should homemade fertilizer be applied?

How often homemade liquid fertilizer should be applied depends on the ingredients and how strong the mixture is.

Always dilute strong fertilizers and follow the recommended instructions for the specific product or recipe.

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?

Liquid fertilizers such as diluted fish emulsion and properly diluted urine can provide nutrients faster than many dry, slow-release fertilizers.

Compost tea may provide small amounts of nutrients, but its nutrient content can vary.

Can natural fertilizers burn plants?

Yes. Even natural fertilizers can harm plants if applied too heavily. Fresh manure, strong fertilizer teas, and concentrated mixtures should be used carefully.

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 your reliance on synthetic fertilizers and recycle household waste in your garden. This approach can help you 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.