Best Fertilizer For Tomatoes

Yes, summer is heating up in many parts of the world, and vegetable gardeners are eager and cannot wait for the first tomato crop to ripen. You need not head out to the shop to buy your favourite fruit as they are sun-warmed and sweet. But it is not always that way, as many things can go wrong with a crop. Some you can fix, and others you can’t. Among such is providing enough fertilizer. Good news because we have all in info right here on the best fertilizer for tomatoes.

The Best Way to Feed Your Tomatoes

Your tomatoes are standing in the vegetable garden looking great. But what more can you do to make them thrive? The truth is the best fertilizer for tomatoes has a lot of macronutrients and essential micronutrients such as:

  • Nitrogen for the continuous growth of the foliage
  • Potassium for continued growth makes it susceptible to diseases
  • Phosphorous for root and fruit development and helps fight stress
  • Magnesium helps keep the plant green
  • Boron helps with the flowering and ripening of the fruit
  • Calcium for leaf and root growth to produce firm tomatoes
  • Zinc to help with the flowering and development of the fruit

When feeding your tomato plants, all these nutrients must be present in varying proportions during each growth cycle. If you’re new to gardening, feeding your plants might be a daunting task, whether growing from seeds or seedlings. It need not be. With the guidance provided here, you are going to have a fantastic tomato crop year after year.

But before we proceed, let’s get one thing clear. There is no such thing as one single tomato fertilizer working in all gardens throughout the year. So let’s get started looking at some facts and plant food options for you to pick the right one based on your plant’s stage of growth.

Tomato Fertilizer Basics

fertilizing tomatoes

When choosing a plant feed for your tomatoes, it all depends on their stage of growth. In contrast, every nutrient needs to be present at all times. The ratio changes with each step of the tomato’s development. Further, most tomato plant roots are not deeper than 7-inches. So keep this in mind when you mix your plant feed into the soil.

Lastly, commercial fertilizer always has a number series known as the ratio of 10-8-10. This stands for nitrogen-phosphorus-potassium or N-P-K. What is means is that the plant fee contains:

  • 10% nitrogen
  • 8% phosphorous
  • 10% potassium
  • The rest of the ratio is made up of filler material or micronutrients.

Type of Nutrients the Tomato Plants Need

Basically, all plants need access to all macronutrients and micronutrients for it to live. For macronutrients, tomatoes need an ample amount of phosphorous for root growth. Potassium helps the plant flower, while for general development, it needs nitrogen. Phosphorous is required in the initial and final stages while nitrogen takes care of the foliage, but too much can lead to a bushy plant with no fruit. Potassium will help the plant grow to produce flowers and fruits.

Different Stages of Providing Plant Food

Depending on whether you plant from seeds or seedlings, there are different stages when it comes to providing fertilizer for tomatoes, as seen here:

  • When planting seeds, they do not need added nutrients to germinate. The reason is that it already contains the amounts to start with growing the first leaves. Here is an excellent guide on how to plant tomato seeds.
  • Now, if you plant from seedlings, they do need plant food as it has already germinated. The plants will grow fast before flowering and typically bears fruit within four months.
  • Once your plant is full-grown, it also needs fertilization and depends on different factors from the soil, environment, and the type of tomato you have.

Importance of Tomato Plant Roots

Another important thing is the root system of the plant. Your choice of plant feed all comes down to how the plant absorbs the nutrients placed into the soil. For the best root health, you need to use the correct watering techniques to encourage deep rooting.

As the plant grows in height and branches out, you may need to provide them with some support to prevent them from falling over. On another important note, it is best to place your plant in the ground or in a big container to avoid clumping the roots. The reason is that clumped roots cannot absorb all the nutrients it needs to grow.

When Should You Fertilize Tomato Plants?

As mentioned previously, you need not fertilize seeds, but you need to provide plant food when planting seedlings and when a tomato plant is full-grown.

Tomato Fertilizer for Seedlings

When planting or transplanting seedlings, it needs nitrogen to grow. Generally, fertile soil has enough nitrogen to provide growth for your plant. Bur, if you use large portions of coconut husk with a filler material, it needs more nitrogen.

The only way to know if your plant needs more nitrogen is by testing the soil. However, the general rule of thumb is if you use fresh compost, there is no need to add nitrogen, just phosphorus is needed at the first stage of growth. That is soon after seedlings are transplanted.

However, if the soil contains a lot of bones and banana peels, you need not add phosphorus. There are two ways you can add phosphorus if required. First, you can use a combination of organic fertilizer spikes and bone meal.

Using Bone Meal

Bone meal is one of the best fertilizers for tomatoes that is organic. It provides your plants with enough phosphorous to grow a robust root system. The plant feed comprises ground animal bones such as beef or fish bones. You find most of the commercial bone meal in ratios of 3-15-0.

Before you add the plant feed, it helps to check the pH level of your soil. If you find it is above 7, then reduce the pH before adding the fertilizer. The plant feed is a slow-release fertilizer and can take up to four months to break down. So for 10 square feet, you only need to apply one pound of bone meal.

Using Fertilizer Spikes

You can also place a fertilizer spike about six inches away from the stem of each tomato plant allowing it to absorb the nutrients from the soil. The best is to choose one with a high amount of phosphorous with nitrogen and potassium. The plant feed can last up to two months.

Fertilizing During the Growth Phase to Pre-Flowering

Here we look at both determinate and indeterminate plants. When it comes to determinate tomato plants, you can cater to their nutrition needs as there is a distinction between the growth phase and fruiting. But for indeterminate kinds, it needs constant plant feed using fertilizers of 8-32-16 or 6-24-24. So the nitrogen content is made up of 1/4 of phosphorous with at least 1/2 of potassium.

tomatoes flower

The nitrogen is essential for pre-flowering as it determines the varieties to form the structure like chlorophyll to aid in photosynthesis. But if you have good compost, you need not concern yourself with adding nitrogen. But if you notice the leaves turning yellow, it signifies that the plant needs nitrogen.

Further, if you want a lot of flowers, it needs a constant source of nitrogen but not too much. Just before flowering until the end of the season, it helps to add potassium as well. The levels should be double the nitrogen, such as 8-32-16 or 6-24-24, and add per instructions.

Or you can make some compost tea using banana peels chopped up into pieces and bury them in the soil. Then, during the plant’s growth, you can keep collecting them and place them in a big container to cover up. Next, you can push the peels close to the roots about an inch below the soil or deeper.

Fertilizing From Flowering to Ripe Fruit

During this phase, your tomato plant does not need large amounts of nitrogen if it has grown well. A crucial nutrient to add is phosphorous for good fruit. The same applies to adding potassium but only once a week.

For the best fertilizer during this stage, you can go for an 8-32-16 plant feed. Once you determine how long your plant takes to flower, you can start feeding them up to two weeks before the time.

Benefits of Using Organic Fertilizers

Compared to commercially bought fertilizers, using organic plant feed has many benefits. The ingredients are naturally occurring plant or mineral matter added. While the petroleum industry chemically synthesizes inorganic fertilizers. Here are the benefits of both:

organic fertilizer


  • The plant feed improves the soil as the organic matter contains trace nutrients instead of only the top three nutrients: nitrogen, phosphorous, and potassium.
  • The nutrients release gradually and last longer.
  • You can find them available in a liquid form such as fish emulsion and a granular form.
  • inorganic fertilizer


  • The nutrients are released fast to get a better timely result that is helpful with tomato plants that has yellowed leaves or if the plant is malnourished.
  • You can find them in granular and liquid forms.

Best Tomato Fertilizer

For growing delicious tomatoes, you need to provide the best fertilizer for your plants. Using plant food will help support the overall health of your tomato plant. It will help with growth, flowering, the fruit development and make it disease resistant. But before we get to check out some of our top contenders, make sure to read this section first:

Types of Plant Food for Tomato Plants

You get three primary forms of plant food:

  • Granular fertilizer applies easily and needs no preparation time. You can incorporate it into the soil before planting or spread it over the root system on established plants. You can buy them in quick and slow-release formulas. In addition, you can find them in organic and inorganic formulations.
  • Liquid plant food has a concentrated formula you need to dilute using water. You can find them in organic and inorganic formulations. You can apply half-strength or less directly to the foliage or use the standard application method to drench the soil around your plant with it.
  • Water-soluble fertilizers are a liquid form and provide immediate nutrients with an application. These are also available in organic and inorganic formulas. In addition, you can find them available in a micro granule or powdered form to dissolve in water.

Our Top Picks

Dr. Earth Home Grown Fertilizer

This is the best tomato fertilizer you can use on herbs and vegetables as well. The product is enriched with proteins, multi-minerals, humic acids, trace elements, and carbohydrates. It helps to promote healthy soil providing your plant with high-quality nutrients. It is a granular fertilizer with long-lasting effects. While a bit more expensive, the price is fair for the quality ingredients used.

Further, it is sustained in the United States and also made the Non-GMO list. The NPK ratio is 4-6-3. Another beneficial thing about this plant food it is human and pet safe. The only downside is to put a peg on your nose as it has a strong smell.

Jobe’s Tomato Fertilizer Spikes

For the best bang for your buck, this tomato fertilizer is easy to use. It eliminates the time wasted on using granules or liquids to feed your plants. All you do is push them in the soil to keep your plant healthy for up to eight weeks.

The spikes provide nutrition through the ground to the roots. So you can use it in raised beds, in-ground gardens, or container gardens. It is a slow-release formula, and the best part the nutrients do not wash away. The NPK ratio is 6-18-6 that is mess-free

EcoScraps Plant Food

For an organic tomato fertilizer EcoScraps is high on the list. The product is made of food waste to keep the landfills in excellent condition and helps to grow delicious tomatoes and veg. It has no manure and completely wastes food blended evenly for perfect results.

You can use it at the beginning of the garden season with a layer of compost followed by spreading. The NPK ratio is 5-4-6. The only problem you may face is that it can attract Fido and does have an unpleasant smell.

Burpee Organic Tomato Fertilizer

Burpee is an organic granular tomato plant fertilizer to use on most vegetables. It is a slow-release tomato plant food. You can till it into the soil of container gardens. Or you can apply it as a top-dressing up to twelve weeks later to use for an entire season. It spreads quickly to release the nutrients immediately, lasting up to three months. The product contains essential microbes and nutrients and has an NPK ratio of 3-6-4. It is easy to apply but does have a strong odour.

Greenway Biotech Water-Soluble Fertilizer

You get the fertilizer in a simple package with quality ingredients designed for tomatoes. If you prefer water-soluble tomato plant food, this product will serve you well. The five-pound packet makes up to 1,000 gallons of liquid fertilizer. You can use it as a dry product to side-dress your plants or add water.

The plant food contains copper, boron, molybdenum, manganese, and zink. The NPK ratio is 4-18-38 and is excellent to use for hydroponics without heavy metals. The downside is you may need to add Epsom salts or calcium nitrate.

Final Thought

If you want plump juicy tomatoes, plant and soil nutrition is vital. For healthy tomatoes, you need to fertilize them, and the best ones support the plant, flower, and development of the fruit. Further, it makes your tomato plants resistant to diseases. We hope that the information on tomato fertilizers here helps you to choose one that suits your needs.

Whether you want to buy, sell or simply reach out to other plant enthusiasts, Plantly is the right place to be!

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