What is Organic Fertilizer? 

person holding compost soil in their hands

It’s no secret that fertilizer is key to a great lawn. It’s a great nutrient source for the soil and balances out its chemicals to maximize health and appearance. Some of the best choices are organic fertilizers. But what is organic fertilizer, and what makes it stand out? 

If you want to discover the benefits associated with this type of fertilizer, keep reading. We explore the ins and outs of this natural and environmentally friendly alternative to traditional chemical options.

What is Organic Fertilizer?

Organic fertilizer is derived from plant or animal-based sources. It undergoes minimal processing and minimizes the ecological footprint linked to the manufacturing and application of traditional synthetic fertilizers. Organic fertilizer contributes to:

  • Excellent grass and plant health
  • Improved soil structure
  • Enhanced plant and grass water retention, helping plants better withstand drought and reducing the need for frequent irrigation (hello, water conservation)
  • Enhanced microbial activity, promoting a thriving ecosystem of beneficial organisms and bacteria
  • Long-term soil health and sustainability
  • The recycling of organic waste, contributing to sustainable lawn care and gardening practices
  • The development of a holistic approach to lawn and garden care
  • Carbon sequestration, mitigating climate change by capturing and storing carbon in the soil
  • Reduced chemical exposure, minimizing the risk of chemical buildup in the soil and water
  • Lower chances of over-fertilization due to slower and more steady nutrient release, proving more forgiving in application
  • Improved plant flavor and nutritional value

The downside? Organic fertilizer costs more, doesn’t release as many nutrients in cooler climates, and depends on microorganisms in the soil to reach its full potential. 

When it’s cold, microbial activity slows down, and the decomposition process isn’t as efficient. As a result, the availability of nutrients also decreases. If cost is an issue, various at-home alternatives make excellent organic fertilizers.

Types of Organic Fertilizer

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The following organic fertilizers offer diverse options for gardeners seeking sustainable and environmentally friendly alternatives to synthetic fertilizers.


  • Nutrient ratio: 2% Nitrogen, 1.5% Phosphorus, 1.5% Potassium, though the nutrient rate highly depends on the organic matter used in the mixture
  • Efficiency rate: Moderate to slow

For a nutrient-dense organic fertilizer, opt for compost. It’s created from decomposed plant material, yard waste, and kitchen scraps. Compost enhances soil fertility, structural integrity, and microbial growth and activity. It’s also an excellent way to suppress potential lawn diseases, improve crop yields, and boost the quality of your plants, fruits, and vegetables. Find out how to start composting.

Cottonseed Meal

  • Nutrient ratio: 6% Nitrogen, 3% Phosphorus, 1% Potassium
  • Efficiency rate: Slow

Cottonseed meal is commonly used as an organic fertilizer. It offers several benefits for plant growth and soil health, including soil acidification for plants that prefer slightly acidic conditions (blueberries, rhododendrons, and azaleas), stimulation of microbial activity, and versatile use for flowers, shrubs, trees, and vegetables.

Bone Meal

  • Nutrient ratio: 4% Nitrogen, 20% Phosphorus, 0% Potassium
  • Efficiency rate: Moderate

You may have heard of bone meal but know little about its uses. This natural source of phosphorus and calcium is derived from ground animal bones, promoting soil fertility, healthy plant root development, flowering, fruit production, and overall plant strength. Plus, it enhances the availability of other nutrients and aids plants in nutrient absorption.

Animal Manure

  • Nutrient ratio: 3% Nitrogen, 1% Phosphorus, 1.5% Potassium
  • Efficiency rate: Moderate to fast

Another valuable organic fertilizer is animal waste. Options include horse manure, cow manure, or chicken manure. Regardless of your choice, this fertilizer type provides beneficial macronutrients such as nitrogen, phosphorus, and potassium for improved soil texture and healthy, long-term plant growth.

Fish Meal (Emulsion)

  • Nutrient ratio: 9% Nitrogen, 0% Phosphorus, 0% Potassium
  • Efficiency rate: Fast

This liquid organic fertilizer is made from decomposed fish. It provides plants with a balanced mix of nutrients (nitrogen and phosphorus) and trace minerals and promotes robust plant growth. Like other organic fertilizer options, fish meal helps improve soil fertility, aids organic farming, and maintains animal health.

Blood Meal

  • Nutrient ratio: 12% Nitrogen, 1.5% Phosphorus, 0.5% Potassium
  • Efficiency rate: Fast

This potent nitrogen source is a byproduct of animal processing, stimulating rapid leafy growth in nitrogen-hungry plants. It releases nutrients quickly, making it a fast-acting agent for nutrient deficiencies. Besides that, it boosts soil fertility, deters pests, and maintains the health of acid-loving plants such as blueberries, rhododendrons, and azaleas.

Kelp and Seaweed

  • Nutrient ratio: 1% Nitrogen, 2% Phosphorus, 5% Potassium
  • Efficiency rate: Fast

For a wide range of nutrients, include kelp-based fertilizers and seaweed in your fertilizing routine. They contain potassium, growth-promoting hormones, and valuable trace minerals, enhancing plant resilience to stress.

Worm Castings

  • Nutrient ratio: 2% Nitrogen, 1% Phosphorus, 2% Potassium
  • Efficiency rate: Slow

Other nutrient-rich fertilizer alternatives are worm castings or vermicompost. The first consists of worm waste, while the second is made up of worm castings mixed with other organic decomposed materials. They serve to improve soil structure, nutrient availability, and microbial activity (more soil microbes present).

Bat Guano

  • Nutrient ratio: 8% Nitrogen, 6% Phosphorus, 1% Potassium
  • Efficiency rate: Fast to moderate

While unlikely, a mix of bat droppings makes a surprisingly good natural fertilizer for your grass and plants. It contains nitrogen, phosphorus, and trace minerals that help with flower and fruit development.

Feather Meal

  • Nutrient ratio: 12% Nitrogen, 0% Phosphorus, 0% Potassium
  • Efficiency rate: Moderate

You can’t go wrong with feather meal for steady, prolonged nutrient availability, vibrant foliage, and overall healthy plant development. This organic fertilizer is derived from ground poultry feathers and contains high levels of slow-release nitrogen. It also enhances soil aeration, water retention, and microbial activity, fostering a balanced soil environment and improved soil structure. 

Its versatility makes it a gardener’s favorite, suitable for fruits, vegetables, flowers, and ornamental greenery.


  • Nutrient ratio: 2.5% Nitrogen, 1% Phosphorus, 1.5% Potassium
  • Efficiency rate: Moderate to slow

Though typically described as a soil amendment, alfalfa is often used as an organic fertilizer for lawns and plants. Its high concentration of organic matter and ability to improve soil structure and release nitrogen, phosphorus, and potassium into the soil make it a winner in the lawn care world.

Nevertheless, alfalfa isn’t typically used on its own; it’s combined with other organic fertilizers and amendments for an optimal, well-balanced diet in the yard. It comes in the form of pellets or alfalfa meal.

Corn Gluten Meal

  • Nutrient ratio: 0.5% Nitrogen, 0.5% Phosphorus, 1% Potassium
  • Efficiency rate: Slow

Many homeowners use corn gluten meal as a source of nitrogen, an essential nutrient for healthy plant development and leafy, green growth. On top of that, this organic fertilizer comes with pre-emergent herbicide properties, improves soil structure, water retention, and microbial activity, and poses few risks to the environment when compared to commercial fertilizers.

Its versatility in various settings such as landscapes, lawns, and gardens, and its safe use around people and pets make corn gluten meal a must-have if you want to go the organic fertilizer route.

Store-Bought Fertilizer

  • Nutrient ratio: Depends on the manufacturer; check the bag for details
  • Efficiency rate: Slow to fast, varying from manufacturer to manufacturer

Of course, last but not least, you can always buy your organic fertilizer at any garden center in your area. Since the quality of store-bought fertilizer can vary, consider these factors when making your selection:

  • Certifications – Look for organic certifications such as USDA Organic or OMRI Listed (Organic Materials Review Institute).
  • Ingredient transparency – Check the label for all ingredients and their sources.
  • Nutrient content – The fertilizer should provide a balanced mix of nutrients for plant growth and align with your lawn care needs.
  • Synthetic components – Avoid purchasing fertilizers that contain synthetic additives or opt for those with minimal synthetic components.
  • Soil compatibility – It’s important to consider whether the fertilizer aligns with your soil type and the plants in your garden. Fertilizers often cater to specific soil conditions and grass/plant types.
  • User reviews – If purchasing online, check out the user review section and consider what other gardeners who have used the product say. They can provide insights into the product’s usefulness and potential problems arising from its use.
  • Application instructions – It goes without saying that you should follow the recommended application rates and guidelines written on the fertilizer bag. These come straight from the manufacturer and are meant to prevent application mistakes that may result in imbalances or plant death.

Organic vs. Synthetic Fertilizers

Fertilizer for grass, lawn, meadow in a bag of white granules on a background of green grass
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The organic vs. synthetic fertilizer debate is longstanding and lies at the heart of modern gardening practices. The choice between the two can impact plant and grass health, soil sustainability, and general environmental health, so it’s no wonder many homeowners take selection seriously.

Some common processed (synthetic fertilizers) include:

  • Urea
  • Ammonium Nitrate
  • Ammonium Sulfate
  • Diammonium Phosphate
  • Triple Superphosphate
  • Potassium Chloride
  • Monoammonium Phosphate
  • Various NPK blends (nitrogen, phosphorus, and potassium)

We already outlined the benefits of organic fertilizer, so how does it stack up against chemical fertilizers? Let’s take a closer look at the critical distinctions between the two.


Organic fertilizer:

  • Is derived from natural, organic sources (mentioned above)
  • Contains a broader range of nutrients than synthetic fertilizer

Synthetic fertilizer:

  • Involves industrial manufacturing and typically contains concentrated forms of nitrogen, phosphorus, and potassium (N-P-K). It also may include other micronutrients like sulfur and magnesium. 

Nutrient Release

Organic fertilizer:

  • The nutrients are released more gradually as the organic matter decomposes. This slow-release process helps to build soil fertility over time and reduce nutrient leaching (the loss of nutrients through excessive rain or irrigation).

Synthetic fertilizer:

  • The nutrients in inorganic fertilizer are released quickly, immediately reaching the plants, which is beneficial if rapid nutrient uptake is needed.

Environmental Impact

Organic fertilizer:

  • Generally speaking, organic fertilizer is better absorbed by grass and plants, minimizing the chances of runoff. Should runoff exist, it poses a lower risk of environmental harm due to the lower concentrations of chemical additives typically found in synthetic fertilizers.

Synthetic fertilizer:

  • In contrast, synthetic fertilizer can harm the environment if used irresponsibly. Some associated risks include nutrient runoff, water pollution, air pollution, greenhouse gas emissions, soil degradation, and ecological imbalances, all related to the production and use of this type of fertilizer. 

Soil Health

Organic fertilizer:

  • By using organic fertilizer, you’re enhancing the health of your soil while supplying it with essential nutrients, increasing microbial activity, and promoting better water absorption and retention.

Synthetic fertilizer:

  • Synthetic fertilizers provide essential nutrients but don’t contribute as much to soil health as organic types.

FAQ About Organic Fertilizer

Does Organic Fertilizer Contain Pesticides?

Although generally speaking, organic farming practices involve using natural and organic materials, this doesn’t necessarily mean that all organic fertilizers are 100% pesticide-free. It varies from product to product, which is why you should consider:

  • The presence of the “certified organic” label, confirming the fertilizer’s pesticide-free composition.
  • Potential contamination concerns from the source materials used to produce the fertilizer. These may contain pesticide or herbicide residues; for example, if you’re using animal sources and the animal was exposed to these substances.
  • Reading labels carefully (if you’re buying organic fertilizer at the store) and understanding the composition. You also can consider contacting the manufacturer directly for questions and clarifications.
  • Using clean materials if you’re making your own fertilizer at home, and knowing exactly what you’re putting in it.

Do Organic Fertilizers Have an Unpleasant Smell?

Yes, especially if you’re using manure to produce your own fertilizer at home. The good news is that this odor usually disappears after application, and many organic store-bought fertilizers contain little to no smell.

Can I Use the Same Organic Fertilizer on My Lawn and Plants?

While you can use organic fertilizer for various plants in the yard (fruits, vegetables, flowers, and ornamental plants), you should provide the right nutrient ratio required by the plant, grass type, or vegetable in question. Fertilizers are typically not one-size-fits-all, so do your homework before starting.

Elevate Your Yard With A Pro’s Help

Using organic fertilizer is a transformative approach to eco-friendly and sustainable lawn care. Adopting it can harness the power of nature’s nutrients while promoting a healthier ecosystem. But what if lawn care just isn’t your cup of tea? 

That’s where a lawn care professional comes in. They can examine your lawn, discuss options, and fertilize it to your liking. Besides that, they can tackle other lawn care tasks such as aeration, mowing, and dethatching. What’s not to love about that?

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Andie Ioo

Andie Ioo

In my free time, I enjoy traveling with my husband, sports, trying out new recipes, reading, and watching reruns of '90s TV shows. As a way to relax and decompress, I enjoy landscaping around my little yard and DIY home projects.