7 Best Organic Liquid Fertilizers for Vegetables & Gardens in 2024

Any good gardener wants to give their plants the very best nutrition in order to boost growth and production. Using the best organic liquid fertilizer for your vegetables and gardens provides a convenient, sustainable way of doing just that. 

Let’s take a dive into the world of fertilizers, full of nitrogen(N), phosphorus(P), potassium(K) and other nutrients tailored to exactly what you want to grow. Whether you’re looking for an organic fertilizer for tomatoes, succulents, flowers, or larger-scale gardening, we’ve got you covered.

Our Top Picks

Here’s a quick look at our picks for best organic liquid fertilizer for vegetables.

A Closer Look: 7 Best Organic Liquid Fertilizers for Vegetables & Gardens

Now let’s dial into the details of each organic fertilizer. You’ll find everything you need to know to make a purchasing decision below.

If you’re wondering: what is the best liquid organic fertilizer for vegetables? Well, this Dr. Earth Tomato Vegetable & Herb formula is a leading contender. From root to flower, this gentle fertilizer helps plants flourish.

We especially love that this liquid fertilizer is multi-purpose, reliable, and easy to use. From container plants to raised beds to more extensive use, Dr. Earth is the liquid fertilizer to reach for when you need the overall best organic liquid fertilizer for vegetables.

The best organic gardeners have long used fish fertilizer as a way to keep their gardens flourishing, improving soil health with each application. 

We like the Kellogg Organic Plus Fish & Kelp Fertilizer in particular because it has molasses for an extra boost. It comes in a smaller container, so you can experiment a bit and invest in a larger amount when you see results. Larger, more expensive jugs of organic fish fertilizer are still a great deal, because a little goes a very long way, and lasts a long time.

Using Urban Farm Texas Tomato food is a great way to give your tomatoes the exact boost of nutrition they need. This formula is made up of basic organic macronutrients like nitrogen, phosphorus, calcium and potassium, plus an extensive combination of other natural ingredients, like worm castings, kelp, mycorrhizae, minerals and the specific enzymes that make tomatoes happy.

(If you’re looking for more tomato-specific fertilizer recommendations, check out our guide to the Best Organic Fertilizers for Tomatoes.)

If you’re primarily growing flowers in your garden, you need a formula that is lower-nitrogen and higher-phosphorus, like the Urban Farm Fertilizers Flowers & Blooms.This flower food is super-potent; one gallon of the concentrate makes 256 gallons of full-strength fertilizer. 

In addition to providing macronutrients, Flowers & Blooms contains worm castings, humic acid, bat guano, mycorrhizae, kelp, enzymes and other essential nutrients. Unlike more multi-purpose fertilizers, these ingredients are specific to a flower’s entire growth span, from stems and leaves to buds and blooms.

What if you’re not growing vegetables or flowers in your garden but instead succulents or cacti? Succulents and similar plants need a diluted level of macronutrients, so make sure to use a fertilizer specially formulated for your garden, like the Espoma Organic Cactus Liquid Plant Fertilizer.

We especially love the “Easy Dose” cap that aids in precision feeding and helps prevent spills.

Let’s talk about the (smelly) elephant in the room. Yes, if you use a seaweed or fish-based fertilizer, it’s going to be stinky. But the smell dissipates quickly — plus the amazing results you’ll experience with this Alaska Fish Fertilizer will have you forgetting about any initial funkiness! 

One of the main advantages of fish fertilizer is that it‘s gentle; it won’t “burn” plants, and it’s very multi-purpose. It works especially well for vegetables that are “heavy feeders,” like corn, tomatoes, cucumbers, etc.

This fast-acting FoxFarm Grow Big liquid fertilizer does just what it says — grows big! And its concentrated formula and larger size make it especially well-suited for larger gardens.

A 6-4-4 NPK formula is a good all purpose base, but Grow Big also contains Norwegian kelp and earthworm castings, as well as a wide variety of micronutrients and trace minerals. The combination results in lush buds and blooms, plus healthier branching and foundational growth.

While the price point of this best organic liquid fertilizer might seem a little steep at first glance, it’s highly concentrated. In fact, the instructions state that all you need is about 2 teaspoons per gallon of water, every other time you water your garden.

Why Choose a Liquid Organic Fertilizer for Vegetables and Gardens?

Here’s a quick guide and FAQ to help you make the best decision for your garden.

Dry vs. Liquid: Convenience

Liquid organic fertilizers are the more customizable choice; they’re also faster and overall easier to use. Dry, slow-release granules and powdered organic fertilizers are highly effective, but they’re also messy, dusty, and need to be worked into soil. Liquid fertilizers, on the other hand, are better for a “quick feed.” They also tend to be more concentrated, so you can adjust how much you dilute them with water, given the type of plant and its growth stage.  

Organic vs. Synthetic 

We highly recommend only using organic fertilizers. While they may result in slightly slower initial growth, over the long run they will provide your plants with natural, sustainable, and gentle support. Organic fertilizers are formulated with naturally occurring plant and animal-based ingredients or natural byproducts (such as composting). Perhaps most importantly, organic fertilizers do not present the danger of mineral or chemical buildup on the surface of soil in the way synthetic fertilizers do.

Synthetic or chemical fertilizers might promote a more dramatic burst of rapid growth, but they are manufactured artificially, using unsustainable practices. They can also be harmful to pets and children, and cause toxic runoff into waterways as they wash away from plants and gardens. 

How to Tell the Difference

A rule of thumb: if your fertilizer is a deeper brown color, and smells earthy or well, a little poopy, you’re likely dealing with an organic fertilizer. If, on the other hand, your fertilizer is a bright color or has brightly colored crystals or beads, and it smells like chemicals, chances are that’s a synthetic fertilizer. Chemical fertilizers tend to be cheaper, but are higher in cost when you consider the need to constantly re-apply, and their overall cost to the environment.

What does it mean if my liquid fertilizer is OMRI-listed? 

OMRI stands for the Organic Materials Review Institute, a nonprofit organization that uses USDA standards to determine whether a product qualifies as organic. If a fertilizer is OMRI-listed, it is free of any chemical or synthetic ingredients and safe to use in organic gardening.

Our Process

For this guide on the best organic liquid fertilizers, our team spent 6 hours researching the most popular options from over 25 brands and manufacturers big and small. We then read about 150 user reviews (both positive and negative) to discover what shoppers thought about each liquid fertilizer. After comparing this data, we narrowed our list down to the top 7 fertilizers on the market. You can count on this research to guide you to a mindful purchasing decision.

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