Best Organic Fertilizers

Best Organic Fertilizers 2020: Reviews & Buyer’s Guide

If you’re a novice gardener, it may surprise you that there is more to it than planting the seed in the soil and watering it on a regular basis.

In order to grow plants in a healthy manner, they must be supplied with enough nutrients.

But it is very unlikely that you will have the perfect soil for every plant in your backyard.

So to supply your soil with the key ingredients it needs, you need to look for the best organic fertilizer.

Now when it comes to organic fertilizers, you have a lot of options available.

If you are new to gardening, the wide array of options can be extremely confusing.

There are so many brands of organic fertilizers available, each having unique characteristics.

To help you make your decision, we have compiled a list of some of the most common fertilizers and discussed each of them in detail.

Top 10 Best Organic Fertilizers 2020

1. Neptune’s Harvest

Neptune’s Harvest is one of the best organic fertilizers for vegetables, especially for tomato plants.

When your plant is not growing properly due to inadequate nutrients in the soil, this fertilizer works quite well.

This fertilizer is good for encouraging growth in both seedlings and mature plants, but with seedlings, you should dilute the fertilizer so that the tender plants don’t get burned.

It is made from seaweed and fish. It is a soil additive that is fast-acting, building the natural sugars in the leaves of your plants.

This helps them grow well, even in extremely hot and dry conditions. It makes the foliage, fruit, and flowers more productive and durable, and even the fruits last longer.

If you wish, you can apply this fertilizer directly to the plant leaves for the purpose of foliar feeding.

The reason it works so well is that it provides a form of nitrogen that plants can easily digest.

When you use this fertilizer on flowers and ornamental plants, they grow more colorful, durable, and fragrant.

Food crops produce more natural sugars when treated with this fertilizer, thus making the fruits, vegetables, and berries tastier. You can easily mix this fertilizer using a drip line, sprayer, or just your hand.


  • Easy to apply when compared to dry fertilizers
  • Best organic fertilizer for vegetables and flowers


  • A bit smelly
  • Animals enjoy the smell

2. Miracle-Gro Performance Organics

If you are new to gardening and searching for the best organic fertilizer for growing your dream garden, then this product from Miracle-Gro is definitely a great choice for you.

Miracle-Gro is a brand trusted by gardeners all over the world, and Performance organics is a revolutionary product that gives your plants the nutrients it needs for healthy growth.

This fertilizer comes in a convenient bottle with an applicator cap that makes it easy to use and apply to the plants.

You just need to shake the bottle and feed the contents to your indoor and outdoor plants.

You will get good results every time, and within 7 days you will notice the difference.

Compared to unfed plants, these plant Nutrition Granules from Miracle-Gro provides a greater bounty of herbs, flowers, and vegetables.

You can apply this fertilizer dry, and unlike products, you don’t need to add water to it.

This product is heavily enhanced with micronutrients for the best results.

You can use this product on garden vegetables, flower beds, and houseplants.

Some gardeners feel, however, that the product contains too much nitrogen.

Because of this, you should exercise some caution while using this fertilizer on outdoor plants so that the nitrogen does not enter the natural waterways.


  • No need to add water
  • Applicator cap makes it easy to administer
  • All-purpose product


  • Need to take extra care because of the high nitrogen content
  • Needs to be applied on a weekly basis

3. Espoma BTSP8 4-3-3 BioTone

This product from Espoma is considered by many to be the best organic fertilizer.

It comprises of fungi, good bacteria, and a concentrated amount of plant nutrients that are easy for the plants to digest.

It is a precisely formulated mixture manufactured with great care that helps plants grow faster while encouraging large root masses.

This fertilizer has high amounts of endomycorrhizal and ectomycorrhizal, the first of which is a fungus that helps the plants to absorb key minerals and retain more water by creating a symbiosis with the roots.

This supplement is totally natural, and it provides plants with good bacteria that help them establish larger blooms, have deeper roots, and prevent the loss of transplant.

This fertilizer contains all the bacteria required by plants to thrive, and all the fungi needed by gardeners to plant vegetable and flowering plants in poor soils.

Immediately after transplanting, this fertilizer promotes the maximum development of the roots.

During the planting phase, this fertilizer is extremely useful as it allows the seedlings to build a durable colony of mycorrhizal fungi so that the plants last longer and adapt to their new home faster.

This fertilizer has an N-P-K ratio of 4-3-4, which makes it possible for gardeners to use it with all kinds of plants.


  • Seven different beneficial fungi
  • Allows plants to utilize more nutrients and water
  • Makes plants last longer


  • A bit pricey
  • Strong odor

4. Espoma Organic EOLF28

With this fertilizer from Espoma, you can feed the plants in your lawn all throughout the year.

This is a fast-acting fertilizer, and soon after adding the product to your soil, you will notice the grass turning greener.

It has several microbes that are beneficial for your plant, and it allows your lawn to readily extract nutrients from the soil.

This is an organic fertilizer and is derived from pasteurized poultry manure and feather meal. Hence, you can use this safely with children and pets around.

Having an NPK rating of 18-0-3, this product is rich in nitrogen, and you should exercise some caution while using it.

Containing 2% non-staining iron, this fertilizer is a great alternative to Milorganite.

It is 100% organic and made from elemental sulfur, iron oxide, and poultry manure.

It is a slow-release fertilizer, so you can use it on your lawn for a long long time.

It does not cause any damage to the lawn, and you can apply it irrespective of the season.

Because of this reason, many gardeners consider this to be the best organic fertilizer.


  • All-nitrogen formulation
  • Can be used during any season
  • Slow-release formula


  • A bit clumpy

5. Espoma Summer Fertilizer

This is a fertilizer made from elemental sulfur, iron oxide, and poultry manure.

It contains non-staining iron 2% by volume and has an NPK formula of 8-0-1.

You can get these products in bags weighing 30 lbs, which should easily cover an area of 5000 square feet.

Since it covers a large area, this is the best organic fertilizer for vegetable garden spread in a larger area.

The Espoma Organic Summer Fertilizer has slow-releasing nitrogen because of which you can witness steady growth over a certain period of time.

This fertilizer is especially beneficial for the plants you grow during the summer season. After applying this to your lawn, you will notice it turning greener.

The slow-acting formula from Espoma allows you to take care of your lawn even during the hottest months.

It contains trace amounts of potassium that protect your lawn from dry conditions when water is scarce.

So you can save some water as a result. This is the best organic fertilizer for creating a strong foundation for your plants during the summer.

This way, you ensure they head into autumn and winter strong and eager to survive.


  • Covers as much as 5000 square feet of your lawn
  • An eco-friendly formula that’s safe for kids and pets
  • Shows immediate results


  • Carries a strong odor
  • Needs to be spread using hands

6. Humboldts Secret Gold Tree

This fertilizer helps in activating enzymes that promote the photosynthesis process in bushes, flowers, trees, and plants.

This is a soil food additive that you can use for any purpose to increase your overall yield quality.

If you are facing problems related to dying trees, wilting flowers, and sick crops, this is the best organic fertilizer you can buy.

Irrespective of the growing method, this fertilizer can help save dying plants and feed the growing ones.It also helps in revitalizing the plants that are struggling to survive.

It is compatible with different growing methods like soil, DWC, coco, aeroponics, and hydroponics.

This fertilizer can provide your garden with all the nutrients it has been missing.

This formula consists of essential minerals, carbs, kelp, and amino acids. You can use only this as an additive, or combine it with other fertilizers and additives.

When you use this on your lawn 1-3 times every week, it helps optimize the photosynthesis process, enhances root development, and also increases the yield.

Whether you are growing garden flowers, house plants, vegetables, or herbs, this is the versatile solution you need.

This product comes in a 2-ounce solution using which you can make 55 gallons of additive for feeding your plants.

With this, you can enhance yields by 20% and vegetation time by 50%.


  • Compatible with different growing methods
  • Increases yield significantly
  • Suitable for any plant


  • May burn blueberry and apple trees
  • Effective only when used with other fertilizers

7. SEA-90 Organic Fertilizer

This product from SEA-90 is often considered the best organic fertilizer because, unlike other fertilizers; it doesn’t produce any awful smell.

Also it is 100% natural and safe. Hence you can easily use this odor-free fertilizer indoors.

Since this product is water-soluble, you can use it with a sprayer or a sprayer bottle.

It is extremely useful for hydroponic applications and for providing nutrients to plants.

This multipurpose fertilizer improves the growth, health, and fruit production of all trees and plants.

So you don’t have to buy several fertilizer types and try different combinations to make things work.

SEA-90 is a versatile product that you can use for flower gardens, citrus trees, row crops, and vegetables.

The company uses 100% organic marine mineral solids in the sea for making this fertilizer.

This product has a certification from the Organic Materials Review Institute, which speaks volumes about its purity and quality.

You can use it as a fertilizer or an additive for livestock feed. This natural product is completely safe for you, your family, and your pets.


  • 100% organic product
  • Water-soluble
  • No offensive odor present


  • Expensive compared to other fertilizers
  • Ingredients not clearly mentioned

8. Fox Farm FX14049

Fox Farm is a popular brand among gardeners. The fertilizer comes in three parts for different stages in the life of a plant.

Grow Big Hydro, the first bottle, can be used for enhancing the growth of foliage.

Tiger Bloom, the second bottle, it for the initial signs of flowers and blooms.

Big Bloom is the third bottle, and it is ideal for the entire growing cycle, and it promotes nutrient cycling and heals the root systems continually.

Its effective trio makes it the best organic fertilizer for vegetables and late-season flowers.

Grow Big encourages vigorous plant growth and is rich in Norwegian Kelp, potassium phosphate, and earthworm castings.

The recommended feed is 12 ml per gallon, but for massive feed, you might use 20 ml.

The Tiger Bloom contains earthworm castings, magnesium, and calcium.

In order to make an organic gardening soil mix, you may combine Tiger Bloom and Grow Big.

The Tiger bloom provides NPK fertilizer feeds, which leads to a healthy plant.

The Liquid Big Bloom contains bat guano and earthworm castings that provide essential micronutrients.


  • Suitable for indoor and outdoor plants
  • Enhances nutrient cycling
  • Improves the root system


  • This is a bit expensive fertilizer

9. Unco Industries Pure Worm Castings

This product contains earthworm castings that are nothing but the digested soil excreted by worms.

These prove to be extremely beneficial for the growth of the plants.

So the effectiveness of such fertilizer depends on the food fed to the worms.

Unco industries always use organic material with minerals and trace elements as worm feed.

This fertilizer is listed in OMRI, which tells you that it’s 100% organic. It is specially formulated for promoting root growth since it contains the correct amount of water-soluble minerals and nutrients.

Several customers are happy with this water-soluble fertilizer, and some even consider this to be the best organic fertilizer.

Your plants quickly absorb the vital nutrients and trace elements present in this product.

Since the worms mix the nutrients evenly, it takes the plants less effort in order to absorb them.


  • Dense in nutrients
  • Promotes optimal growth of roots
  • Nutrients are broken down to their simplest form


  • Need to supplement this with another fertilizer

10. Espoma Garden Tone Herb & Vegetable Fertilizer 

Many folks consider this to be the best organic fertilizer as it is specially developed for professional gardeners and is a popular choice for vegetable gardens and residential herbs.

The Garden Tone has 15 organic ingredients like soluble potash, phosphate, and nitrogen.

Additionally, it contains Espoma’s unique blend of several beneficial microbes that enhance that plant’s DNA to ensure delicious herbs and vegetables and better plant growth.

This plant food is made in the USA, and it contains no toxic or hazardous ingredients.

Since it is safe for the environment, it will not add any toxins to the soil, nor will it burn your plants with its naturally low salt content.

It has a slow-release formula that good for established plants as well as seedlings.


  • Especially made for vegetable gardens and herbs
  • Safe for the environment
  • Balanced food for plants


  • Strong odor
  • Bone meal present


1. What Is A Complete Organic Fertilizer?

A complete organic fertilizer or a COF is one that is made entirely of organic substances in a perfectly balanced mixture.

2. Which Fertilizer Makes Plants Grow Faster?

Fertilizers high in nitrogen promote growth in plants. This is why many fertilizer companies include nitrogen in their products.

3. Can Eggshells Be Used As Fertilizer?

Calcium is a mineral necessary for building the cell walls of the plants, and eggshells provide plants with this vital mineral.

4. Is Organic Fertilizer Better Than Chemical?

Chemical fertilizers are cheaper than organic ones, but they may damage your plants because they are highly concentrated. Hence organic fertilizers are a better option.