Finding a good organic fertilizer can be difficult. Organic fertilizers are wrongly misunderstood to be ineffective with low nutrient levels, which makes artificial fertilizers more popular.
However, if you find the correct organic fertilizer that suits your soil condition and plant types, you’ll be able to see results that last much longer than those produced by a chemical fertilizer.
In this article, you’ll discover which organic fertilizers are worthwhile, as well as know how to choose the fertilizer type you truly need so that you don’t invest money in the wrong products.
The Best Organic Fertilizer Right Now
To save you the trouble of looking and searching for effective organic fertilizers, we’ve put together a list for your convenience. This list contains organic fertilizers that we reviewed and found to have passed our assessments and quality tests.
We’ve categorized them into seven different categories to make it easier for you, so read on to discover the best organic fertilizer that most suits your needs.
1. Best Overall: Jobe’s Organics All-Purpose Fertilizer Spikes
Jobe’s Organics All-Purpose Fertilizer Spikes are absolutely brilliant. The spikes are easily driven into the ground near the plant’s roots, saving you the mess that would’ve resulted from other fertilizer applications.
This organic fertilizer has an NPK ratio of 4-4-4, with many other trace elements. Also, it’s registered on the Organic Materials Review Institute’s list, so it’s 100% organic with no artificial and synthetic chemicals.
Plus, it contains microbes that break down the fertilizer to increase its efficacy and efficiency. On another note, the spikes can be dug up with animals, so keep them away until they can fully dissolve.
Easily carried and stored
Listed in the OMRI
Has microorganisms for faster results
A bit expensive if used for large areas
Animals can dig up the spikes
Can be smelly
2. Best on a Budget: Espoma PT18 Plant Tone
The Espoma Plant Tone is a versatile fertilizer that can be used on trees, shrubs, flowers, and vegetables. It has a 5-3-3 NPK ratio, and it slowly releases these nutrients over a lengthy time period, granting you durability.
It’s made of a combination of mineral, animal, and plant-based fertilizers, in addition to other salts and minerals. It also contains microorganisms, which break down the fertilizer particles and result in faster nutrient delivery and plant growth.
However, it has a bit of a strong smell, so it’s better to use it outdoors to disperse the smell and make it less noticeable.
Suitable for different plant types
Relatively inexpensive, yet still quite effective
Strong odor that can attract animals
3. Best for Lawns: Scotts Natural Lawn Food
For lush lawns and turfs, the Scotts Natural Lawn fertilizer is the perfect choice. It can be applied at any given time to all grass types, producing good results each and every time. Four applications per year are more than enough to create and sustain a flourishing, green lawn.
Once applied, you can walk on it immediately, and you can see results in as fast as 1-3 weeks.
This organic lawn fertilizer is chemical-free, and it’s also OMRI listed. Moreover, it’s completely safe for both kids and pets, so don’t worry if your dog or child accidentally ingests this fertilizer.
Safe for pets and kids
Suitable for different grass types
Its smell isn’t too overpowering
Can burn the grass if applied excessively
4. Best Liquid: Fox Farm Liquid Nutrient Trio Soil Formula
The triple set of Fox Farm Liquid Fertilizer is an excellent purchase for both beginners and experienced gardeners, consisting of three different bottles; Grow Big, Tiger Bloom, and Big Bloom.
Grow Big is used at the beginning to stimulate plant growth until the flower buds start to form. Then, Tiger Bloom is used because it’s very rich in phosphorus. Lastly, the Big Bloom is used for fruiting and flowering plants for maximum nutrition and root health.
These fertilizers have to be diluted in some instances, or else the plants may burn. Research your plant’s requirements before applying any of them.
Suitable for various fruiting and flowering plants
Easy to use and apply
Needs to be diluted when used with certain plants
5. Best Starter: Espoma BioTone Starter Plus Plant Food Fertilizer
The Espoma BioTone Starter Plus Fertilizer is a mix of organic fertilizer types, made up of greensand, feather meal, alfalfa meal, bone meal, poultry manure, and other ingredients. It has an NPK of 4-3-3, and its nutrients are slowly released over time.
The fertilizer has 13 types of microbes for optimal root and stem formation, and it also contains humates for increased plant uptake of nutrients.
This organic garden fertilizer is best used when you’re just starting your outdoor planting endeavors or when you’re repotting your indoor plants. Yet, thoroughly mix it in with the soil to reduce its smell.
Suitable for various plants
Product smell and consistency may slightly vary from batch to batch
6. Best for Flowers: Dr. Earth 707p Organic 8 Bud & Bloom Fertilizer
Made from a blend of rock phosphate, feather meal, fishbone meal, and alfalfa meal, the Dr. Earth 707p Organic 8 Bud & Bloom Fertilizer is a great option for flowering plants.
For starters, it allows for better root formation, which results in a greater quantity of buds and flowers. This is due to its high phosphorus content, with an NPK of 3-9-4.
Not to mention, this fertilizer gives your plants all the nutrients they need and will last you for many months. Also, it doesn’t contain any sewage sludge or chicken manure, making its smell considerably better than other organic fertilizers.
Has no GMOs
Rich in phosphorus
Contains beneficial microbes
The packaging is a bit weak
7. Best Soil Builder: Unco Industries Worm Castings Organic Fertilizer
If you want an amazing organic soil builder and fertilizer, then Unco Industries Worm Casting Fertilizer is the answer to your prayers. It’s suitable for almost all plants and is loaded with both macro and micronutrients for your plants’ benefit.
The earthworm castings can provide both fast and long-term nutrition, so your plant will be able to have what it needs when it needs it.
It also improves your soil structure and aeration, which results in more extensive and stronger plant roots. Leaves, buds, flowers, and fruits take the energy that would’ve gone into the roots and make themselves known.
Quick and long-term nutrients
Improves soil condition
Has no smell
Reduces damage from pests
Can lose its efficacy if not stored in a dark and dry place
How to Choose an Organic Fertilizer
Organic Fertilizer Types
There are three main types of organic fertilizers; mineral, animal-based, and plant-based.
This variety of organic fertilizers comes from natural rocks and sands. That means they’re not artificially made and have no chemicals in them. Since they allow for a chemical-free planting, they were thus dubbed organic.
There are two varieties available, rock phosphate and greensand. The former has a high level of phosphorus, while the latter has a high potassium content. Both contain traces of other minerals like nitrogen, iron, calcium, magnesium, copper, and many more.
Did you know? Rock phosphate doesn’t immediately dissolve in water and remains in the soil, slowly releasing its nutrients till they’re called upon by the surrounding plants.
There are numerous types of animal-based fertilizers, manure and urine being the most common. Bone meal, blood meal, and fish meal are also popular and are made from what their names indicate. Some other types include shell meal, fish emulsion, seabird guano, and many others.
These fertilizers are rich in the major three minerals. Except for fish emulsion, all types release their minerals a bit slowly, so don’t get them if you want a quick fix.
Pro tip: Blood meal can burn your plant if used excessively as it’s highly acidic, so use with caution.
Plant-based fertilizers are what you want if you need a slight nutrient boost. They’re suitable for soil preparation and conditioning as they have natural stimulants and enzymes that’ll help your plants grow healthy and fast.
They include compost, alfalfa meal, cottonseed meal, soybean meal, corn gluten meal, seaweed, grass clippings, and more.
If you need a nitrogen-rich fertilizer that doesn’t involve animals in any way, fortunately, cottonseed meal and soybean meal are one such fertilizer.
Dry vs. Liquid
A dry fertilizer doesn’t work if the microorganisms do not break it down in the soil. So you have to incorporate the fertilizer into the soil and thoroughly mix the two for this to happen.
Since it’s long-acting and encourages plant growth for a long time, it’s best used with seeds and transplants.
Conversely, liquid fertilizers deliver a fast punch of nutrients into the soil. They can be directly applied to the soil or sprayed on the plant’s leaves.
Leafy plants that are starting to grow are the optimal recipient of this fertilizer. However, beware that newly-sprouted seedlings can only withstand a diluted version of this fertilizer.
When choosing your organic fertilizer, you have to look at its NPK ratio. This ratio represents the weight percentage of the three major nutrients; nitrogen, phosphorus, and potassium. Each one of these macronutrients is essential for the different processes a plant goes through as it grows and flowers.
Organic fertilizers also contain micronutrients needed by plants in lesser amounts for their general health and well-being. These nutrients include iron, copper, manganese, boron, chlorine, zinc, and molybdenum.
To make the fertilizer more effective, microorganisms like beneficial bacteria and fungi are often included in the fertilizer. That’s because they increase the amounts of nutrients available for uptake and use by the plants.
Different plants need varying amounts of nutrients for optimal growth and development. For example, some plants require high nitrogen levels, while others benefit more from phosphorus and similar.
That’s why fertilizers come in different NPK ratios to suit specific types of plants better. For example, lawns need high nitrogen levels, not so much the other two. On the other hand, vegetables generally require relatively high equal levels of the three elements.
Moreover, bulbs require lots of phosphorus for strong roots, while trees and shrubs benefit from low to moderate levels of the three macronutrients every now and then.
Depending on what you want to see happen, different types of fertilizers should be used. If you’re just starting a new garden, you won’t benefit from a liquid fertilizer. That’s because your goal should be to raise the fertility of your soil, so soil builders and dry/granular fertilizers are the way to go.
In contrast, if you already have an established garden with plants in various development stages, a burst of nutrients from a liquid fertilizer is what you need. It’ll allow your plants to grow well and reach their full potential.
Your soil’s condition will directly affect the type of fertilizer you’ll use. So, make sure to check your soil’s pH, organic content, and nutrient content with a soil test first.
If you find your soil unsuitable for planting purposes, then you need to modify its composition and supplement it with what it lacks.
For sandy or rocky grounds, you have to add abundant amounts of mulch, which adds the organic material needed for plant growth. Compost, bark chips, leaf mold, cow manure, and other animal manures are all excellent sources of organic matter. Follow the mulch with soil builders and organic fertilizers.
Synthetic vs. Organic Fertilizers
Gardeners and farmers sometimes use synthetic fertilizers for fast and instantaneous results. However, these results come at a cost.
Over time, the fertility and quality of the soil drop, while its acidity shoots up due to the high salt levels in any synthetic fertilizer. This acidity eventually burns the roots of young plants and stops their growth. These fertilizers also drive away beneficial earthworms.
Meanwhile, organic fertilizers preserve and improve your soil’s quality as time goes by, where they increase soil moisture and aeration.
And if you want fast results, don’t forget that organic liquid fertilizers are available.
How Can You Tell if Fertilizer Is Organic?
Besides checking the fertilizer’s label for the word “organic”, you can check if the fertilizer is listed in the OMRI. Its product list only contains truly organic materials that have been measured against strict organic standards.
Also, look at the ingredient list of your fertilizer. If it has superphosphate, potassium sulfate, potassium chloride, ammonium nitrate, or other synthetic ingredients, this fertilizer isn’t organic.
How Do You Apply Organic Fertilizer to Plants?
Organic fertilizer generally takes some time to work because you have to wait for the soil microbes to break down the fertilizer into ready-for-use nutrients. This can take two weeks in warm weather, but cold weather can double or triple this duration.
So consider your climate and apply your granular fertilizer in the top 3-6 inches of your soil before you plant the seeds. Pour or spray liquid fertilizers when extra nutrients are needed.
Can You Over-Fertilize Your Plants With Organic Fertilizers?
Yes, of course. Excessive fertilization will harm your plants, whether the fertilizer is synthetic or natural. It’ll burn off the plants and alter the soil’s composition, making it hard for new plants to grow. In addition, insects and fungi may seriously infest your ground, and consequently, your plants can contract and suffer from various diseases.
What Natural Fertilizer Is High in Nitrogen?
Blood meal, feather meal, and urine/urea all have pretty high levels of nitrogen. The nitrogen levels can range from 12 to 15 percent in those organic fertilizers. Bat guano and seabird guano also have high nitrogen contents, reaching 10 percent nitrogen.
And if you want a plant-based alternative, cottonseed and soybean meals have decent nitrogen levels, coming at 6% and 7%, respectively.
What Are the Disadvantages of Organic Fertilizers?
One drawback of organic fertilizers is the relatively low nutrient levels when compared to synthetic fertilizers. This can result in smaller and less green plants. Another disadvantage is that it takes a longer time for the fertilizer’s effects to be noticed.
Moreover, the fertilizer’s composition may vary from batch to batch because organic products are biologically active. This can, unfortunately, produce unpredictable results, which can be very annoying since most organic fertilizers aren’t exactly cheap.
What Type of Nutrient Is the Most Important for the Plants?
Nitrogen, phosphorus, and potassium are the three major nutrients needed by plants. Some plants may need one of those nutrients more than others, but all are still important.
Nitrogen is usually the nutrient that plants lack the most as it can rapidly leave the soil in gas form. The other two are more stable and remain in the soil for longer durations.
Other micronutrients are still of value to plants, but to a lesser extent.
- Don’t expect instantaneous results with organic fertilizers as it takes time for the soil microorganisms to break it for the plants’ easy use.
- Liquid fertilizers are faster than granular ones.
- Jobe’s Organics All-Purpose Fertilizer is the best dry fertilizer, while the Fox Farm Trio formula is the best liquid one.