Fertilizer for Tomatoes: Everything You Should Know and Our Recommendations

Think your tomato plants are struggling to grow? Need a quality fertilizer for tomatoes to help them thrive?

You’ve come to the right place.

When the summer arrives and the tomato starts to bloom, it’s time to add some fertilizer. But what type of food should you add? At what moment, and how?

Don’t get stressed by all these questions. The answers are simple. Below, we give you everything you need to know and more – check it out!

Basics of Tomato Fertilizer

The first and more important thing to know about fertilizer for tomatoes is that it depends.

Different stages and different soil conditions require variable approaches to the fertilizer. There’s a general rule to follow: it is crucial to ensure all nutrients.

What does that mean? Well, you need a fertilizer that offers nitrogen, phosphorous, and potassium at once. Additional nutrients are worth adding, but these three are the most essential.

Another worthwhile thing to know is that fertilizer is no replacement for quality soil or a well-composted garden. Even though fertilizer can make up for both, it won’t be enough.

And lastly, tomato plants are generally easy to grow. That means there’s a chance you can grow it without adding any fertilizer. But for sustained growth that goes rapidly, fertilizer would be your best help.

When Should You Fertilize Tomatoes?

While it feels like tomatoes may need fertilizer from the moment you plant them until their fruits are already harvested, they do not.

There are specific times when fertilizer should be applied and moments when you should avoid it. We explain more about each stage below:

Seeds

If you’re starting the tomato plant from seeds, you won’t need to apply any fertilizer. Tomato seeds sprout quickly without any extra nutrients (as long as the soil is rich enough).

Seedlings

You should apply the fertilizer as soon as the first leaf sprouts. If planting a seedling, make sure the soil is already fertilized.

The first few weeks of growth are essential for the plant. With more nutrients, you can ensure more and faster development.

Grown          

Keeping the plant fertilized can be immensely helpful. Here, however, you should fertilize lightly. That means using a slow-release or mild fertilizer. Keeping the soil prosperous every 10 to 21 days should be enough. For nutrient-rich soil, you can fertilize once a month, and that will suffice.

What Are the Essential Nutrients of a Tomato Fertilizer?

Regardless of the plant growth stage, it must contain a few nutrients. These include nitrogen (N), phosphorous (P), and potassium (K). Below, we explain these three and a few fillers you should also consider:

Nitrogen

For rapid foliage growth and denser plants, you should use nitrogen. It keeps the tomato thick and healthy.

Phosphorous

Ideal to protect the roots and developing fruits, phosphorous is the best initial-stage and late-stage nutrient.

Potassium

Improves growth rate and helps produce more fruit. It also helps with photosynthesis and helps the plant develop disease resistance.

Calcium

The most helpful filler, it helps with foliage and fruit. Every leaf will be stronger and larger, plus every tomato will be healthier.

Magnesium

Keeps the foliage green and vibrant. It is the perfect nutrient for ensuring a beautiful tomato that develops rapidly.

Boron & Zinc

Both nutrients do the same: aiding in the flowering stage and the fruit-ripening period.

As you may guess, the ratio of nutrients in different fertilizers varies enormously. Some have more nitrogen than phosphorous, others have more potassium than nitrogen, and so on. Fillers like calcium, magnesium, and boron/zinc are not essential but could also make a bit of a difference.

Types of Fertilizer for Tomatoes

With all the basics of fertilizer figured out, let’s give you a heads-up about what types of fertilizer to consider depending on your exact needs. And how the tomato will develop according to the type you pick.

Granular

The first type you’ll find is granular. As the name says, it comes in granules, small particles the soil absorbs over time.

It is generally a slow-release alternative, usually lasting several weeks or months before the soil absorbs it all.

Some quick-release granules are absorbed within days of application. However, these are often chemical alternatives, which are not the healthiest.

Liquid

When the fertilizer comes in a pour-in bottle, that’s a liquid option. It needs to be diluted with water to work. Otherwise, it could be too strong for the plant (and cause over-fertilization).

The fertilizer is often of rapid release, making the soil richer within a few days of application.

You can find it with either organic or inorganic ingredients. It also comes with different ratios of nutrients according to the specific needs of the plant.

Water-Soluble

Confusing, we know. But water-soluble fertilize is like a granular option in terms of strength and the quickness of liquid.

Like the granular, it comes in a granule-like or powdered presentation. By dissolving it in water, this fertilizer is ready to be applied on any soil.

It acts super-quickly and delivers enough fertilization for a few weeks.

Organic vs.Inorganic Tomato Fertilizer

Believe it or not, there’s not much difference. Whether you decide to fertilize with organic or inorganic fertilizers, the plant won’t care.

But in case you prefer something natural, more organic, that keeps your plant growing without adding unnecessary chemicals, then an organic option is the way to go.

Besides, organic fertilizers tend to have additional nutrients that inorganic options don’t have. This helps the plant even further without causing any side effects.

Having said that, inorganic options still have their advantages: they release quicker, stay for longer, and typically help the plant grow further (are a bit stronger).

For most people, organic fertilizers are the best alternative simply because they prevent chemicals from being passed to the fruits. But between adding no fertilizers and adding chemical ones, go for the chemical option all the way.

Our Recommendations for the Best Fertilizer for Tomatoes

With almost everything about fertilizers figured out, let’s show you some of the best fertilizers out there.

These are the fertilizers we think everyone should consider. There’s a variety for pretty much everyone. Check them out:

1. Lilly Miller Morcrop Tomato & Vegetable

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A natural alternative for people who don’t want a single bit of chemicals in their vegetable garden, the Lilly Miller Morcrop gets the job done like no other.

It stands out for its 5-10-10 ratio. This means it has more potassium and phosphorous than nitrogen, making it an excellent addition for the plant in its mature state.

People who want the plant to grow the densest foliage and provide more fruits will prefer this one.

This also happens because you can find all kinds of essential minerals that help grow and fruit production.

Thanks to its granule presentation, it is a slow-release option. This makes it ideal for monthly applications.

As for specific results, the manufacturer claims to improve the taste. While we can’t confirm that, we’re sure it won’t be the opposite. So, why don’t you give it a try?

2. Miracle-Gro Plant Food

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For those who prefer cheap and effective over anything else, Miracle-Gro comes with a perfect alternative.

This is a water-soluble food, meaning it needs constant reapplication and is absorbed rapidly. Every 14 days should suffice to make it work effectively.

To apply, you only need to use a watering can. Mix two tablespoons per 1 and a half-gallon of water. That will keep your plant thriving.

What are you getting? An excellent ratio of 18-18-21. That’s enough nitrogen, potassium, and phosphorous to help throughout any stage.

The best about this food is the additional array of nutrients. It contains almost everything your tomato will need to keep growing past the harvesting stage.

3. Espoma Tomato-tone Organic Fertilizer

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Boasting an all-natural composition, this fertilizer has everything you need to keep that tomato plant thriving.

This includes a 3-4-6 NPK ratio, alongside other 15 essentials that will make even the poorest of soils a lot richer.

Among these nutrients, you’ll find an outstanding 8% of calcium. This prevents most diseases and keeps the blooms extra healthy.

It will sustain any tomato’s growth, ensuring more foliage density and higher yields. And thanks to the slow-release composition with Bio-Tone Microbes, it keeps working even after months of application.

Last but not least, it is a granule fertilizer. Applying it to your garden soil shouldn’t be much of a problem.

4. Jobe’s Vegetable & Tomato Fertilizer

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A water-soluble fertilizer that works quickly yet keeps nurturing your tomatoes for weeks – that’s what Jobe’s offers.

It starts with a 3-1-2 mix in a 10-ounce box. When diluted, it makes up to 30 gallons, so you can pour over your plants for months with this single box.

The composition is unique, boasting a Biozome, a proprietary blend with microorganisms that breaks down quicker than many other fertilizers.

Given how easy it is to use and how fast it acts, there’s no doubt this is one of the best, especially for mature tomatoes.

5. Miracle-Gro Shake ‘N Feed Tomato

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Granules in an easy-to-use bottle, with enough content to feed your plant for more than 3 months, and still featuring entirely natural ingredients: that’s what the Shake ‘N Feed is all about.

From Miracle-Gro, one of the best manufacturers of gardening products, this fertilizer nurtures your plant like no other. It develops stronger and denser foliage, healthier fruits, and way fewer diseases overall.

This is all possible to the high-calcium composition. Yet, it is also the 12-4-8 NPK ratio that makes it stand out, boasting more nitrogen than anything else for an extra boost of growth.

The application is incredibly straightforward as well, making it a pleasure to use at all times. It offers the whole package of features, so you can rest assured your tomato will thrive.

What to Consider When Buying a Tomato Fertilizer

So, what should you take into account when picking a tomato fertilizer? What are the most important factors? And how will you know if it is the right one for you?

Here are some features to consider:

Ingredientsand Nutrient Ratio

When surfing through the different options above, you’ll realize how different they are all.

Some come with a ratio of 18-18-21, while others are only 3-1-2 in total NPK content. Each of these will give you a completely different result.

But with that in mind, it’s worth knowing that fertilizers with smaller NPK ratios are often filled with additives. These can be either organic or inorganic. The focus is to add micronutrients like calcium, sulfate, magnesium, and boron or zinc.

Other additives may include microorganisms. These may help to improve the speed of the product or how much it lasts. In some cases, it comes with additives that help protect the root and prevent diseases.

Growing Stages 

Every tomato plant will require different fertilizer compositions depending on its growth stage. Balanced fertilizers with the same ratio of NPK are usually the best for the general user.

But if you want better seedling growth, focus on nitrogen. In case the plant is already matured, go for higher phosphorous and potassium. And if you’re looking for the best harvest, consider those with high micronutrients.

Release Speed

Some fertilizers are quick-release, meaning they are absorbed by the soil almost right away. Others will last weeks before being completely absorbed.

This will tell you a lot about which one to go for. For example, mature plants prefer slow-release fertilizers, as they’re often playing the long game. But small growing plants typically benefit from quick-release versions, as they demand a rapid boost of nutrients to sustain their rapid growth.

Quantity & Durability

How much fertilizer do you need? The quantity will depend on whether you pick a liquid, a granule, or a water-soluble product.

For example, 10 ounces for a water-soluble fertilizer may give over 30 gallons of total product, which could sustain several months. A bottle of liquid fertilizer with one half-gallon can last two months or more. And a 10-pound bag of granules is enough to keep several tomatoes nurtured for 3 months.

Method of Application

What method do you prefer? Once again, granules, water-soluble, and liquid all have different ways of application.

Granules are spread over the soil. They slowly break down and get absorbed.

Water-soluble fertilizers are absorbed almost instantly, lasting several days in some cases. You need to mix the solution with water and spread using a watering can or hose.

Liquid fertilizer is poured directly over the soil. It breaks down super-quickly.

How to Use Fertilizer for Tomatoes

Now it’s time to teach you how to make that fertilizer work. Luckily, it is not rocket science, and pretty much anyone can get it done regardless of the method of application and type of fertilizer.

Here are a few steps to take:

1. Start by preparing the fertilizer as needed. This is primarily true for water-soluble and liquid fertilizers. Granule options may not need any preparation.
2. Follow the instructions for the application. Generally, it’s about pouring directly into the soil, close to the stalk of the tomato plant.
3. To make sure it is absorbed, water the area consistently for the next few days and weeks. This should help break down the product.
4. Reapply the fertilizer according to the instructions. Most fertilizers will need reapplication within the first 2 weeks.
5. Keep doing the same until the fertilizer empties, and you’ll be giving your tomato plant better growth for sure.

For the best experience making a fertilizer work, it’s worth reading the instructions of the specific package you’re using. This will save you a lot of frustration.

Frequently Asked Questions (FAQs)

Have any doubts regarding fertilizers? We may answer them below:

Do grown tomato plants need fertilizer?

Yes. While not always necessary, fertilizing a grown tomato can help prevent issues like diseases and stunted growth. It also helps with foliage density and promotes quicker fruit production.

How much fertilizer per tomato plant?

This depends on the plant’s size, what type of fertilizer you’re using, and the quality of the environment. Generally, you will find the instructions of the product to tell you how much to use.

Can tomato fertilizer be used with other plants?

Yes. This includes flowers and other vegetables.

How often do you fertilize tomato plants?

The frequency depends on what type of fertilizer you’re using. Water-soluble fertilizer requires an application once or twice a month. Soluble fertilizer needs to be applied at least once every two weeks. And granules may need two or three applications every season.

Conclusion

A fertilizer for tomatoes is nothing out of the extraordinary. As long as you follow our advice and pick one of the recommended options, you should have no problem getting that plant to thrive.

Remember, all plants require different fertilizers depending on their stage and environment. Don’t stick with one type or strategy. Adapt as necessary.

With that in mind, there’s nothing to lose now. Get a fertilizer that matches your tomato’s needs and get it working now!