10 Best Organic Fertilizers for Plants

Using organic fertilizers is essential for growing plants. They help to improve soil fertility and boost plant growth.

There are plenty of fertilizers on the market. However, the most effective organic fertilizers for plants are those that provide a balanced blend of essential nutrients.

Nutrients such as nitrogen, phosphorus, and potassium, as well as other micronutrients. All these micro and macronutrients are important for the growth and development of plants.

Organic fertilizers are made from natural sources, such as composted animal manure, plant-based materials, and other organic substances. As well as improving soil structure and water retention, they improve nutrient availability.

Also, there are several factors to consider when choosing an organic fertilizer for your plants, such as the type of plant and the growth stage.

The right organic fertilizer will help your plants grow healthy and strong, giving you a bountiful harvest. To help you choose the right organic fertilizer for plants, I have picked the top 10 organic fertilizers. So, let us see in this article how each fertilizer can make your plants grow well.

Why Do Plants Need Fertilizer?

When plants are grown indoors, they don’t get the same ecosystem they would if they were outside. Hence, without assistance, they deplete the soil’s resources and finally wither away.

No doubt, there are some minerals you can get by water, but most need organic matter too. Thus, it’s essential to use fertilizer and pick the right potting soil.

By choosing the right fertilizer, you’ll get the right nutrients for your plants and pest protection. Also, it doesn’t matter if a houseplant requires more fertilizer or less, all indoor plants need it eventually.

When you can, use organic, natural fertilizer. It’s better for your plant and the environment. Using artificial fertilizers incorrectly or too frequently can burn plants. Also, production contributes to pollution.

Now that you know why organic fertilizer is important for your plants, let’s talk about the 10 best organic fertilizers for plants you can use.

Our Top Picks

Coast of Maine Stonington Lobster & Kelp Plant Food

Let’s learn more in detail about these best organic fertilizers for plants

Best Organic Fertilizers for Plants

1. Espoma Organic PT18 Plant Tone

PROs	CONs
Great for indoor and outdoor	Not suitable for pets
Slow-release	Bag not resealable
Contains bio-tone

This is an excellent indoor and outdoor fertilizer that is appreciated by trees, shrubs, vegetables, and herbs.

If you want to fertilize your grass, this is also a fantastic option. Spread it out as directed and thoroughly water it to dissolve the fertilizer.

As it is a huge quantity, it is ideal to purchase it and renew your entire greenery set at once! Since it is a slow-release, you should only require it once a year.

If you’re applying it on already-planted plants, bury the appropriate amount beneath a couple of inches of soil. Then, mix it with the soil and distribute it evenly when using it in the repotting process.

2. Coast of Maine Stonington Lobster & Kelp Plant Food

PROs	CONs
Slow-release	Quite expensive
Full with nitrogen
Simple to distribute

This granular fertilizer is warranted to continuously release nutrients over an extended period of time. It is an excellent feed for hungry plants like polka dot plants due to its high nitrogen content. The use of porous perlite improves drainage, aerates the soil, and facilitates root growth.

To help the fertilizer stay in place, work it into the top layer of soil when you’re fertilizing existing pots. When replanting in a new pot, mix it with the potting soil according to the directions.

Overall, you can use these organic fertilizers for plants with confidence. In addition to keeping your heavy feeders happy, it encourages growth and healthy roots.

3. Dr. Earth Organic 5 Tomato, Vegetable & Herb Fertilizer Poly Bag

PROs	CONs
No GMOs	May attract pets and pests
Slow-release
Contains pro-biotics

I advise feeding your herbs and veggies with this fertilizer. As indicated, tomatoes can be grown as miniature indoor plants, and this product is created especially for them. Additionally, this fertilizer can be used as a compost tea for rosemary and other herbs.

It is produced domestically and responsibly in the USA, and numerous organizations and initiatives have recognized it as non-GMO.

Rather than synthetic chemicals, this organic fertilizer for plants contains minerals, proteins, carbs, and humic acids.

Keep in mind that leaving it on the soil’s surface could attract both pests and fungus gnats due to the organic content.

4. Neptune’s Harvest Organic Hydrolyzed Fish & Seaweed Fertilizer

PROs	CONs
Easy to apply	Not safe for pets
All-purpose	Bad packaging
Covers large area

This fertilizer is excellent and all-natural, and it works quickly and visibly. For the majority of indoor plants as well as your outdoor and garden plants, I heartily suggest it.

Additionally, this fertilizer is easy to use since it dissolves in water. This tiny bottle is also quite effective, feeding up to 2000 square feet of greenery.

Although it works for the majority of plants, I would suggest it for gardens and outdoor plants. You can use it on trees, bushes, and lawns too. It’s good on asparagus, too.

To avoid attracting pests within, mix a less intense solution and be cautious not to spill any. Pets shouldn’t be around this product as there’s a risk they’ll try to eat it and the concentrate could be dangerous.

5. Humane NutriDense Indoor Plant Food

PROs	CONs
Safe for animals	Small amount
Easy to use
Naturally occurring bug resistance

This is a fantastic fertilizer for all plants, but because it starts releasing nutrients quickly, I especially suggest it for succulents and tropical plants.

You can directly add this fertilizer to the soil in your pots thanks to its convenient shaker. It is created in the USA locally and has balanced primary, secondary, and micronutrients.

This organic fertilizer’s cinnamon extracts offer defense against fungi, insects, and other pests. Moreover, it can benefit your plants now and in the future as it contains nutrients with both rapid and delayed releases.

Water your plants after adding 1-2 teaspoons of fertilizer to the soil. Although it won’t burn the roots, only use it once a month to prevent the plants from becoming reliant on it. Despite being child and pet-safe, keep it out of the reach of both.

6. Down To Earth Organic Kelp Meal

PROs	CONs
Eco-friendly	Might draw mice
Plant-based	Package quickly rips
Nutrient-rich

It’s the perfect all-in-one fertilizer for gardeners looking for something that’s as natural as possible, while also being environmentally friendly.

Seaweed from the Atlantic Ocean makes up the entirety of this fertilizer. Since other leaves typically provide fertilizer for plants, it is an excellent organic material for enhancing veggies, herbs, flowers, perennials, and all other types of plants.

Since they are accustomed to growing alongside dense vegetation, most shade-loving plants fall into this category.

For stronger plants, kelp meal works well in place of rooting hormones by gently stimulating the formation of roots. This promotes development, lessens transplant shock, and generally strengthens the plant’s defences.

On top of that, it offers a natural source of amino acids, trace elements that water would not, and plant hormones.

7. HollandBasics 4-4-4 Organic All-Purpose Fertilizer

PROs	CONs
Easy to use	Expensive
Great for all plants
Generous quantity

You’ll need this fertilizer if you’ve got a huge garden or lots of big potted plants. An excellent fertilizer for potted plants, trees, shrubs, gardens, and landscapes. I would surely advise it for your lemon tree!

Also, it’s an excellent option for springtime fertilization of all of your greens. In addition, it contains fine rock powder and carbon, so your plants get all the nutrients they need.

8. Joyful Dirt Premium Plant Food and Fertilizer

PROs	CONs
Simple application	Only certain plants
Pet and child security	Small quantity
Compact structure

A variety of plants, including basil and jade, love Joyful Dirt. Also, it is fantastic for promoting plant growth and quality improvement as well as for bringing that half-dead rescue plant back to life.

As mentioned, the majority of plants love this organic fertilizer. However, it’s a concentrate, so overusing it will upset your plants.

Overall, it’s quite simple to utilize these concentrated organic fertilizers for plants. Apply a small amount (as directed) to the soil’s surface. After that, water it.

It is advisable to combine some of this product with water before applying it to drought-resistant plants.

9. Miracle-Gro Performance Organics

PROs	CONs
Easy to use	Attractive for pets
Slow release
Fast result

Thanks to Miracle-Gro’s organic ingredients and compost, your big indoor plants will thrive. It takes just a week to see results!

These organic fertilizers for plants are convenient to use and easy to apply thanks to the applicator on the cap. Put it in your pots or under your trees and it will release nutrients slowly.

For best results, combine the grains with the soil. If you’re using it outdoors, scatter some around the base of the plant and incorporate it into the top layer of soil.

Pets will become interested in the same organic substance, so keep it out of reach and bury it deep. Overall, the organic variety is ready to advance you and your plants. For large, organic trees and plants, I recommend it.

10. Milorganite Slow-Release Nitrogen Fertilizer

PROs	CONs
Slow-release	Contains phosphorus, so outdoor is regulated
Rich in nitrogen
Covers large areas

Many gardeners love this fertilizer, and the results speak for themselves. The bag may be expensive, but it covers a lot of ground and will last you for years.

You can use this 32-pound bag for a long time or cover a larger area. This nitrogen-rich fertilizer will make your tropical plants happy.

Just bury it a few inches under the surface or use it directly on the soil. Also, you’ll be feeding your plants for a long time since it’s a slow release. I advise using it for your tree, Aloe vera, Swiss cheese plant, and several terrarium plants.

How to Fertilize Plants: Uses and Care

Although the majority of fertilizers come with their own unique directions, there are a few general guidelines you may use for all fertilizers.

Don’t overfeed your plants, for instance. While some fertilizers work and deplete rapidly, others take longer.

Use them only as directed by the directions on the pack. Even natural, organic fertilizers used in excess might suffocate a plant.

You might also bury your solid fertilizers as an example. They might arrive as dust or solid pellets, but after being rehydrated, they return to their original state as decayed organic matter.

Since it can draw pets’ attention and perhaps vermin if left on the surface, you want a covering of dirt between you and that.

When your plants can utilize the nutrients, fertilize. Some plants don’t need additional nourishment during the winter since they are dormant or stationary. For instance, until it begins to grow once more, a dormant Oxalis won’t require fertilizer.

Last but not least, keep in mind that fertilized plants don’t require more water than unfertilized ones. They might even require a little less watering. Keep an eye on your plant and adjust to its requirements.

Conclusion

Compared to synthetic fertilizers, organic fertilizers for plants offer a natural alternative.

Among the best organic fertilizers for plants is Espoma Organic PT18 Plant Tone, Coast of Maine Stonington Lobster & Kelp Plant Food, Dr. Earth Organic 5 Tomato, Vegetable & Herb Fertilizer Poly Bag, Neptune’s Harvest Organic Hydrolyzed Fish & Seaweed Fertilizer, Humane NutriDense Indoor Plant Food, Down To Earth Organic Kelp Meal, and HollandBasics 4-4-4 Organic All-Purpose Fertilizer.

There are advantages and disadvantages to each of these fertilizers, but they all provide plants with nutrients.

Consider your plants’ specific needs when selecting the best organic fertilizer, as well as the safety of your pets and other animals who may come into contact with the fertilizer. Also, make sure you follow the instructions for use and use the right amount of fertilizer.

In general, organic fertilizers promote plant health and growth, and these organic fertilizers are great places to start for those who want to make the switch to organic gardening.

Product Name	Product Image	Buy Link	Description
Espoma Organic PT18 Plant Tone		Buy Now	All purposes fertilizer. Applicable to all flowers, vegetables, trees, and plants. Increase the number of blossoms with a more intense colour. Develop larger plants with darker green foliage. Bio-tone bacteria provide long-lasting, slow-release nutrition. Contains no fillers or sludges and is made entirely of natural and organic components.
Coast of Maine Stonington Lobster & Kelp Plant Food		Buy Now	This blend stimulates leafy green growth, budding, flowering, and fruiting. This plant food is a fantastic granular organic fertilizer that will boost soil biology. It’s created with natural components like lobster, crab, fish, and kelp meal, as well as worm castings and other natural ingredients. It also contains a lot of calcium, which promotes plant growth. This product can be used to top-dress existing plants or put into the soil for new beds. With all of these applications, this organic plant food is a must-have!
Dr. Earth Organic 5 Tomato, Vegetable & Herb Fertilizer Poly Bag		Buy Now	A mix of fish bone meal, feather meal, kelp meal, alfalfa meal, soft rock phosphate, fish meal, mined potassium sulfate, humic acid, seaweed extract. Strains of beneficial soil microbes, as well as Ecto and Endo Mycorrhizae, make up Dr. Earth Organic 5 Tomato, Vegetable, and Herb Fertilizer. Feed tomatoes, winter and summer vegetables, herbs, root crops, mature vegetables, and during transplanting are the main uses for this product. Formulation 5-7-3.
Neptune’s Harvest Organic Hydrolyzed Fish & Seaweed Fertilizer		Buy Now	Blend of organic fish and seaweed from Neptune’s Harvest the advantages of fresh fish and the deep-northern, cold-water seaweed Ascophyllum Nodosum are combined in the organic fertilizer 2-3-1. The fish and seaweed blend Neptune’s Harvest includes vitamins, amino acids, enzymes, and growth hormones. Additionally, it includes the natural macro- and micronutrients found in fish. Since nitrogen and other nutrients have already been chelated, plants can easily consume them. Neptune’s Harvest keeps the fish proteins and oils intact, unlike fish emulsions.
Humane NutriDense Indoor Plant Food		Buy Now	The Humane brand’s flagship product, Nutridense, is designed for the typical plant enthusiast. No matter where your plant is, you may apply & forget this product because it is made to be both pet and user-safe (Indoor or Outdoor). Nutridense is an easy, all-natural, and organic plant-feeding choice for all your plants’ needs, coming in a convenient 5 oz shaker jar. Switch to another brand to notice the difference. The 5oz NutriDense Shaker makes it simple and practical to feed your indoor plants. Simply open the lid, shake the water and product about the plant’s base, and don’t worry about metering the product.
Down To Earth Organic Kelp Meal		Buy Now	Down To Earth Kelp Meal is a 50-pound bag of all-natural fertilizer with a 1-0.1-2 mix that is approved for use in organic cultivation by the Organic MaterialsReview Institute (OMRI). Kelp Meal is pure Ascophyllum nodosum seaweed harvested from the clean, cold waters of the North Atlantic Ocean, and it is an excellent nutrient supplement for many types of vegetables, herbs, flowers, and perennials. Stimulates root development, reduces transplant shock, increases growth, prevents fungal issues, and relieves stress caused by temperature variations. Hand-harvested, properly dried, and finely milled, this product is ideal for use in seeding mixes and potting soils; simply use 1 to 2 pounds for every 100 square feet of garden soil. Potash, trace minerals, amino acids, and natural plant hormones are abundant in this plant.
HollandBasics 4-4-4 Organic All-Purpose Fertilizer		Buy Now	The fertilizer GAIA GREEN All Purpose is fantastic for gardens and landscapes. This mixture contains a variety of materials and is the only all-purpose fertiliser to contain fossilised carbon complex and glacial rock dust. The components of this potent mixture offer a variety of crucial nutrients needed for thriving plants and promoting soil health. All Purpose has been successfully utilised by certified organic farmers, professional landscapers, and gardeners for the past three decades. Use GAIA GREEN All Purpose to fill your organic garden with bounty.
Joyful Dirt Premium Plant Food and Fertilizer		Buy Now	With just a shake at each watering, Joyful Dirt Organic Based Houseplant Fertilizer and Plant Food will provide your indoor plants with all the nutrition they require. Even when used excessively, Joyful Dirt is gentle enough to not burn plants yet potent enough to provide results right away. 3 ounces of liquid plant food will fit in a 3-gallon shaker. Concentrated, houseplant-specific plant food that is organic-based. Shaker bottle for simple application to any indoor green, leafy plants. CONTAINS – Mycorrhizae and other nutrients to promote the growth and water efficiency of houseplants. GROWTH – Noticeably bigger and more vibrant houseplants. Our patented plant food will work swiftly to show results.
Miracle-Gro Performance Organics		Buy Now	Miracle-Gro Performance Organics Edibles Plant Nutrition Granules are made specifically for producing tomatoes, veggies, herbs, and fruits thanks to their blend of natural and organic components. Apply dry and then add water to begin feeding. Feed tomatoes, vegetables, herbs, and fruits with Miracle-Gro Performance Organics Edible Plant Nutrition Granules. Essential nutrients are provided by OMRI-listed plant food for larger yields (vs. unfed potted plants) Enjoy Miracle-Gro outcomes using natural and organic products. For optimal results, reapply every 4-6 weeks and water often.
Milorganite Slow-Release Nitrogen Fertilizer		Buy Now	Best for Veggies and flowers Contains slowly released nitrogen, aiding in the production of thick Green lawns with minimal top growth and iron for improved greening No salts are present in the non-burning composition. Keeps itself in the soil, ready to work when later moisture arrives. 85% of the product is organic and is biopreferred certified.

Top 10 Organic Fertilizers: Boost Your Plant Growth Naturally