What is 19-19-19 Fertilizer Good For? – When and How to Use It?

With hundreds of fertilizer options, selecting the appropriate option for your plants can be challenging.

Do you choose an organic or synthetic option? Liquid or granules? What NPK ratio should you look for?

We’re going to dive into what a 19-19-19 fertilizer consists of and also include some recommendations for how to use this fertilizer. While it’s not a fit for every type of plant, you’ll better understand how to use 19-19-19 fertilizer when you’re down reading.

What Is 19-19-19 Fertilizer?

A 19-19-19 fertilizer always contains 19% nitrogen, 19% phosphorus, and 19% potassium.

To learn more about NPK ratios and fertilizer numbers, read our article on the subject.

While the 19-19-19 tells you about the percent of the three macronutrients, it doesn’t tell you much else. A triple 19 fertilizer may only contain these macronutrients, or it may also contain other nutrients like magnesium and sulfur.

Reading the product label can give you a full picture of the nutrients a 19-19-19 fertilizer contains.

What Is 19-19-19 Fertilizer Used For?

A 19-19-19 fertilizer is used for crops that require large and equal amounts of nitrogen, phosphorus, and potassium. It is often applied to plants in the spring when they are just starting to resume their growth.

Triple 19 fertilizer can give grass lawns, hayfields, vegetable fields, and trees the nutrients they need in the spring.

However, this fertilizer is often not a good option when plants are more mature. That’s because plants often require different amounts of nitrogen, phosphorus, and potassium when they are older.

I’m going to cover more details about using 19-19-19 fertilizer for different plants below, so stick with us.

Types of 19-19-19 Fertilizer

Triple 19 fertilizers are made up of synthetic nutrients. That’s because synthetic products typically contain more nutrients per weight than organic products.

However, you can find various forms of synthetic 19-19-19 fertilizers.

Granular Fertilizer

As its name suggests, a granular fertilizer consists of small granules. When these granules dissolve in water, the nutrients become available to plants.

You can apply granular fertilizer by sprinkling it on the soil surface with your hands or spreading it with a fertilizer spreader. Applying this fertilizer right before it rains is best so it can dissolve and work its way into the soil.

Most types of granular triple 19 fertilizer supply plants with nutrients as soon as the granules dissolve in water. However, some types of extended-release granular fertilizers slowly release their nutrients over a few months.

Liquid Fertilizer

It’s uncommon to find 19-19-19 fertilizer. However, you can find solid 19-19-19 fertilizers that are designed to be used in foliar applications.

Rather than applying these fertilizers to the soil and watering, you dissolve the granules in water and spray the product on the plant. This is known as foliar feeding, and can quickly supply plants with nutrients.

When and How to Apply 19-19-19 Fertilizer?

Before determining the application rate and timing of 19-19-19 fertilizer, you’ll need to consider the plant type you’re fertilizing. I’ll review how to use triple 19 fertilizer for some common crops.

Grass Lawns

While you can use 19-19-19 fertilizer for established lawns, it’s not the best option. Triple 19 fertilizer won’t harm your lawn, but if you buy a fertilizer, you might as well choose the best one for the job.

Instead of choosing a balanced fertilizer, you should opt for one with large amounts of nitrogen, a bit of potassium, and no phosphorus. For example, a fertilizer with an NPK ratio like 32-0-4 is a better option than one with a ratio of 19-19-19.

With that said, 19-19-19 fertilizer can be used as a starter fertilizer for newly seeded lawns. The larger amount of phosphorus will help the plants establish strong roots and the potassium will help the new plants move water and nutrients.

You should apply five pounds of 19-19-19 fertilizer for every 1000 square feet of new lawn.

You can look at your spreader to determine the setting that will allow you to apply the correct rate, as each type of spreader has different calibration settings.

After the initial application of 19-19-19 fertilizer, I recommend switching to a fertilizer with an NPK ratio like 30-0-4 or 33-2-5.

Vegetable Gardens

I always like to conduct a soil test before fertilizing my vegetable garden. This lets me know what nutrients are already in the soil and how much I need of each one. With this information in hand, I can select a fertilizer that supplies just the nutrients my soil needs.

However, applying a balanced fertilizer can be a good starting point if you choose to forgo a soil test. Adding triple 19 fertilizer to your vegetable garden before planting will give your plants a good nutrient base.

I recommend adding a 19-19-19 fertilizer to your garden about a week before or after planting in the spring, right before rain is predicted. Alternatively, you can water your garden after fertilizing.

A good application rate is five pounds per every 1000 square feet.

After applying 19-19-19 fertilizer in the spring, I like switching to more specialized fertilizers.

For example, fruiting crops like tomatoes, peppers, cucumbers, and melons like higher amounts of phosphorus and potassium. Some suitable NPK ratios include 3-5-4 and 10-15-15.

Trees

When it comes time to fertilize trees, 19-19-19 fertilizer can be a great option. This product supplies trees of all sizes with the macronutrients they need to thrive.

And since this fertilizer contains a relatively high amount of nitrogen, potassium, and phosphorus, you won’t need to apply much of the product to meet the tree’s nutrient needs. However, it also means that you’ll also need to be extra careful not to over-apply fertilizer and cause nutrient burn.

Aim to add fertilizer once per year in the early spring. This applies to shade trees, evergreen trees, and fruit trees like apple trees.

Use the size of the tree to determine how much fertilizer to apply. Measure the trunk’s diameter one foot above the ground and apply one pound of fertilizer for each inch and a half of the trunk’s diameter.

Sprinkle the fertilizer evenly around the base of the tree’s trunk and then water well.

Houseplants

Due to the high nutrient content, I do not recommend using 19-19-19 fertilizers for houseplants. If you apply a triple 19 product, you risk burning your plants with nutrients.

A better option is to choose a product with an NPK ratio like 1-1-1 or 3-3-3.

Flowering Plants

A 19-19-19 fertilizer can provide flowering plants with a boost of nutrients in the early spring when new growth is starting to form. That means triple 19 can be a good option for plants like azaleas, roses, and hibiscus.

However, it’s important to remember that triple 19 contains a relatively high amount of nutrients. That means that you only need to spread a small spoonful around the base of each plant in the spring.

After this initial application, I recommend switching to a fertilizer better suited to flowering plants. Flowering fertilizers contain lower amounts of nitrogen and higher amounts of phosphorus and potassium to support flower production.

Hay

While many people forgo fertilizing hay fields made up of crops like alfalfa, Timothy grass, or tall fescue, applying fertilizer can help encourage a healthy crop. Applying 19-19-19 fertilizer can give your hay fields some nutrients they need to grow.

However, there may be better choices than triple 19 fertilizer for hay fields. It’s important to remember that when you harvest the plants for hay, you remove the nutrients they contain. And these plants don’t contain equal amounts of nitrogen, phosphorus, and potassium!

Instead, plants include lots of potassium, a medium amount of nitrogen, and a small amount of phosphorus. That means if you apply triple 19 fertilizer, you will likely be under applying potassium or overapplying phosphorus.

A better option for your hay fields is to choose a fertilizer that is high in potassium and low in phosphorus. A product with an NPK ratio similar to 20-5-30 is a better option.

Food Plots

If you’re growing a food plot for animals, you can use 19-19-19 fertilizer to encourage and support plant growth. Triple 19 fertilizer is best used as a starter fertilizer. After your plants are established, you should switch to a fertilizer with more nitrogen than phosphorus and potassium.

The best time to apply 19-19-19 fertilizer for food plots is before or right after you plant. Calibrate your spreader so it applies 10 to 15 pounds of fertilizer per acre.

How Long Does It Take 19-19-19 Fertilizer to Work?

Most types of 19-19-19 fertilizer begin to supply plants with nutrients as soon as the product dissolves in water. However, it may take a while before you begin to see plant changes.

If your plants were nutrient deficient, you should begin to see them bounce back within a few weeks after you apply fertilizer.

My Top Choices for Triple 19 Fertilizers

Looking for a 19-19-19 fertilizer for your plants? Then check out the following options.

The Andersons 19-19-19 Fertilizer

The 19-19-19 fertilizer from The Andersons is a classic triple 19 option. It contains 19 percent of nitrogen, potassium, and phosphorus in an easy-to-apply granular form.

This is a synthetic product, and nutrients become available to plants quickly after they dissolve in water.

Although this product contains a big dose of the three macronutrients, it doesn’t contain any secondary nutrients or micronutrients. Therefore, you may need to apply another type of fertilizer to supply your plants with these nutrients.

Since this product is in a granular form, you may want to use a spreader to apply it. This will allow for quick and even application.

You can purchase The Andersons 19-19-19 Fertilizer online from retailers including Standish Milling and Michigan Agricultural Commodities. Expect to pay between $30–$35 per 50-pound bag.

Grasshopper 19-19-19 Foliar Fertilizer

While many fertilizers are applied to the soil before planting, you can also foliar feed to supply growing plants with nutrients. This involves spraying your plants with a nutrient solution.

Grasshopper 19-19-19 is designed for foliar feeding. According to the product supplier, you should mix one 25-pound bag into 24 to 30 gallons of water and then spray on your plants.

If you fertilize hay, corn, or other large-acreage crops, you should apply 25 pounds of product for every two acres. Before you begin spraying, calibrate your sprayer to apply this rate.

You can reapply this fertilizer about every month to continuously supply your crops with nutrients.

This product contains 19% nitrogen, phosphorus, and potassium, plus some other nutrients. It contains 0.5% iron, 0.1% zinc, 0.05% born, 0.05% copper, 0.05% manganese, and 0.001% molybdenum.

You can purchase Grasshopper 19-19-19 Foliar Fertilizer on Amazon. At the time of writing, a 25-pound bag cost $64.00.

Frequently Asked Questions

Can You Use 19-19-19 Over Clover That Is Already Growing?

While you can technically apply 19-19-19 fertilizer over clover, this isn’t the best option. Since clover is able to fix nitrogen from the atmosphere, you typically do not need to supply it with nitrogen fertilizer.

How Much 19-19-19 Fertilizer Should I Apply Per Acre?

If you are applying 19-19-19 fertilizer as a starter fertilizer for lawns, food plots, and hay, you should apply between 10 and 15 pounds per acre.

Is 19-19-19 a Good Fertilizer for Vegetable Gardens?

A 19-19-19 fertilizer can be a good starter fertilizer for vegetable gardens. However, larger fruiting crops like tomatoes and peppers can benefit from a fertilizer with more phosphorus than nitrogen.

Wrapping Up

If you’re looking for a balanced fertilizer that supplies a larger dose of nutrients, a 19-19-19 fertilizer can be a good choice. It can make a great starter fertilizer for lawns, food plots, hay, vegetable gardens, trees, and flowering plants.

Photo of author

Briana Yablonski

Briana holds a B.S. in Plant Sciences from Penn State University and has been working with plants, soil, and ecology for over ten years. She spent five years working on vegetable farms throughout the East Coast before starting her own farm in 2020. She has been writing about plants, food, and science since 2019.

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