Can I Apply Fungicide and Fertilizer At The Same Time!

When it comes to fertilizing and treating your lawn, there are often a lot of questions about what you can and can’t do at the same time. One of the most common questions is, can I apply fungicide and fertilizer at the same time? 

The answer is yes, you can use fungicide and fertilizer at the same time. Generally, there are some fertilizers and fungicides that are compatible with each other and can be used together.

However, you must only use these substances in conjunction with each other if both of them need to be watered in your yard. Let’s talk about how and which fertilizers and fungicides can be mixed.

What Is Fungicide in Plants?

Fungicide is a type of pesticide used to control fungal growth. Fungicides work by damaging the fungal cell wall, which can lead to fungal death. 

Fungicides are available as liquids, granulate, or sprays and are often used in conjunction with other fungicide products to provide greater control over fungus growth. 

What Is Fertilizer?

Fertilizer is a plant food that is added to the soil to make it more fertile. It helps plants to become healthier and produce food. They contain the nutrients that the plants need to grow and thrive. 

Fertilizers come in a variety of forms, including granules, liquids, and pellets. To improve their effectiveness, they’re usually mixed with other substances, such as rocks or compost. Fertilizers also help plants absorb more water and nutrients from the soil. 

Can I Apply Fungicide And Fertilizer At The Same Time?

Definitely, yes, you can use both fertilizer and fungicide simultaneously. In many cases, gardeners will apply fungicide to their plants in order to protect them from disease. 

While this is an essential step in protecting your plants, it’s also important to remember that fungicides are toxic chemicals. When used improperly, they can harm your plants as well as the environment. 

Can I apply Fungicide And Fertilizer at the same time

If you’re applying a fungicide that needs to be watered in, you can apply fungicide and fertilizer simultaneously. When you’re using granular fertilizer, it requires water to break it down into the correct form, so the soil can absorb it. 

However, if you’re using an application fungicide that is activated by water, it’ll be enhanced by the combined action of the fertilizer and water. For instance, you can choose, Good Hostas fertilizer , Fertilizer for orange tree in this case.

Certain fungicides must be dried on leaves and grass after application in order to be effective. In case, you intend to use a non-specifically stated fungicide to irrigate after you’ve applied it, don’t apply fertilizer in conjunction with it.

How Do I Safely Apply Both Fungicide And Fertilizer At The Same Time?

Since fungicides and fertilizers work in different ways to combat plant diseases, it can be tempting to apply them separately. However, this can lead to overuse or misuse of either product and may not provide the best results. That is why many farmers seek to apply them together.

Nevertheless, make sure to follow the tips mentioned below:

Make a schedule

Make a schedule and follow it closely to get the most out of your fungicide and fertilizer treatments. This will help you avoid over-treated plants and maximize each chemical’s effectiveness.

Consult The Label

Always consult the label before using any pesticides or fertilizers! Both products have specific instructions for use that must be followed carefully in order to avoid injury or damage to your plants.

Use Low Doses First

Some fungicides and fertilizers can be mixed together safely. However, it is best to start with the lower dose first, wait a few weeks for the plants to show if there are any adverse effects, and then increase doses gradually.

Keep Track Of How Much Product You Apply

If you have to ask how much of a chemical to use, you probably don’t know what the correct amount is. The label will tell you the correct amount to use.

Apply In The Morning

The best time to apply fungicide or insecticide is in the morning because it is cooler and less likely to damage foliage.

What Type Of Fungicide Can Be Applied With Fertilizer?

There are many fungicides available, so it’s important to choose the correct one for the fungus being controlled. Fungicides can be classified by their mode of action. For instance, 

  • Chemical fungicides, such as azoles and triazoles, kill fungi by disrupting the cell wall of the fungus. They’re effective against a wide range of fungal species. 
  • Systemic fungicides work through the plant’s system and kill fungus on all parts of the plant. 
  • Biological fungicides use natural enemies of fungi to control the pest. 

At present, chemical fungicides are mostly used in combination with fertilizers. However, biological or organic fungicides have also shown promising results.

In general, fertilizers require water in order to be activated and washed into the ground. Whilst fungicides are intended to be sprayed onto the blades of grass or plant leaves to kill the fungal infections that might blossom on them. 

Spot spraying fungicide applications with fertilizer can help control fungal diseases in plants. However, liquid fungicides should not be washed off the blades of grass, or they will be infectious. 

There are some granular forms of fungicides that need to be watered in, and they can be added directly to the soil as a fertilizer. 

Before that, you have to put both fertilizer and fungicide in parallel with each other on a spreader. This makes the process of treating your lawn more efficient, as you’ll only be spraying it one time.

However, when it comes to applying fertilizer and fungicide together, it’s best to stick to granular products. Since both fungicide and fertilizer can be watered, there’s a double incentive. There won’t be a risk of any dilution of your fertilizer.

Which One’s The Best Fertilizer To Mix With Fungicide?

The best fertilizer to mix with fungicide depends on the specific product and the needs of the plants being treated. Rates of application, soil type, crop type, and desired outcome all need to be considered to create a perfect mixture. 

In addition, there are many fertilizers that can be mixed with fungicides to improve the effectiveness of the treatment. So, choosing the right fertilizer to mix with fungicide can be a daunting task. 

As per my research and exploration, I  found certain types of fertilizers to be most effective in mixing with fungicides. These include:

1. Non-Burning Fertilizers

Non-burning fertilizers are beneficial to mix with fungicides because they provide a slow release of nutrients that helps suppress fungal growth. 

Slow-release fertilizers also allow the use of lower concentrations of fungicides, which can be more effective and safer for the environment.

Mixing fungicides with non-burning fertilizer like the Milorganite 0636 Organic Nitrogen Fertilizer has been found to be effective at killing fungal spores while sparing the plants’ roots and foliage.

This combination can help control some common garden fungi without causing injury or damage to your plants.

2. High-nitrogen Fertilizers

Fertilizer like the Scotts Turf Builder Lawn Food, which is high in nitrogen, can be quite effective when mixed with fungicides. 

Treating lawns with this type of fertilizer provides a boost of nutrients and triggers the plant to produce its own natural defense mechanism that helps fight off fungal infections.  

Lawns that receive a balanced fertilizer, including nitrogen also tend to have better growth rates and increased resistance to pests and diseases. 

Since fertilizer includes fungicide for newly planted grass, it`s ideal to use a lawn starter fertilizer when using fertilizer for lawns and gardens. 

These fertilizer products have been specially made for new sod. They’re also able to be mixed with soil fungicides with great outcomes.

Lawn starter fertilizers like the Pennington UltraGreen contain a combination of nitrogen, phosphorus, and potassium which are all necessary for the growth of lawn grass. 

Mixing this fertilizer with a fungicide can help to prevent weed growth and protect the turf from fungal damage. 

3. Gypsum Fertilizer

Even though gypsum fertilizer is mostly appreciated for solo use, it can also be used in conjunction with fungicides. 

There are several benefits of gypsum due to its abundance of calcium and sulfur. So, it would be a great way to improve the health of your lawn

Gypsum fertilizer like the Espoma GG6 Garden Gypsum Fertilizer works to break down organic matter in the soil, which makes it an excellent choice for use with fungicides. 

While fungicides will help to kill any fungus that may be causing problems with your lawn, gypsum fertilizer will help to improve the soil’s texture and fertility. 

However, gypsum can cause fungal growth if mixed with pesticides known to harm fungi, such as chloropicrin or malathion. 

So, it’s important to consult a pesticide guide for specific information about using these products together.

What Type Of Fungicide You Shouldn’t Mix With Fertilizer?

Most suitable liquid fungicides cannot be mixed with fertilizers since they do not need to be watered first. If you’re dealing with a liquid solution, you’ll have to apply them separately at least three days prior to each other.

It’s probably best to leave one or two weeks between spraying your yard with fertilizer and fungicide, if possible. 

What Type Of Fungicide You Shouldn’t Mix With Fertilizer

Often nutrient shortages cause the grass to turn yellow or brown, and this is sometimes mistaken for fungal disease. It’s wise first to apply fertilizer spikes to your lawn to see whether your grass perks up. 

You may discover that your grass greens up and looks healthy, in which case you won’t need to use a fungicide.

It’s generally not recommended to mix a copper fungicide with fertilizer, as doing so may slow the dispersion of the fertilizer. 

In most cases, the copper fungicide should be applied before the ground has dried, the liquid copper fungicide should be left for 12 hours, and the fungicide should be used in dry weather.

So, as opposed to applying the products at precisely the exact same time, apply the fungicide first and then wait 3 days before applying the fertilizer.

How Long to Wait After Mixing Fertilizer and Fungicide?

It’s always to wait at least 3 days before applying fertilizer on your lawn where you’ve already applied a liquid fertilizer. 

This is because you’ll need to water your garden or lawn to activate the fertilizer, while this water can interfere with the effectiveness of the applied fungicide. 

As I have mentioned earlier, you won’t need to wait, if you intend to sue granular variation for both fungicide and fertilizer. 

It’s ideal to allow at least one-week in-between applications to ensure that your lawn can absorb the fertilizer and fungicide you need to apply alternately if necessary.

This will allow you to observe the difference in your lawn’s appearance resulting from using each application.

Tips On Using Fungicides And Fertilizers At The Same Time

While using fungicides and fertilizers simultaneously may seem like a simple solution, it can be difficult to get the correct mix of these chemicals. The wrong combination can cause damage to crops.

For instance, applying nitrogen fertilizer when there is a fungicide applied to the plants will cause the fungicide to be washed off and the nitrogen fertilizer to be ineffective. So, reminiscence of the following advice before you get started:

  • Always read the product label before using any pesticide or fertilizer. There may be specific instructions for using them together.
  • In general, you should avoid using either product when there is an adjacent crop being grown; this includes any kind of citrus. 
  • Try to target a specific fungus with your fungicide, rather than treating the entire plant. This will help to minimize damage to other plants in the area. 
  • Be sure to water your plants well following treatment with a fungicide or fertilizer, as this will help wash away any toxins that were used.
  • Wait at least two weeks before planting new crops in the area treated with fungicides and fertilizers to allow the soil to properly absorb these substances. 
  • Monitor plant health regularly; if necessary, adjust your dosage or application schedule as needed. 
  • Avoid applying more than one fungicide to the same plant at a time. 

Will Fertilizer Make Fungus Worse?

Fungal diseases often attack lawns with deficient fertilizer or overfertilized lawns. If the lawn is stressed due to drought or poor pH level in the soil, it will become more vulnerable to fungal diseases, such as lawn rust or brown patch disease.

In that case, by maintaining the proper timing of lawn care to apply a wide-ranging fertilizer, you can give your lawn the required nutrients to permit it to fend off infection.

To prevent mold growth caused by excessive fertilizer, use a low-nitrogen, low-phosphorus organic fertilizer. It is particularly important in the early spring and the hottest periods of the year when lawns may be damaged due to too much fertilizer application.


How long after applying fungicide can I fertilize?

It depends on the type of fungicide you intend to use. In general, you should wait at least three days before applying fertilizer on your lawn where you’ve already used a fungicide.

Does fertilizer feed fungus?

Most fertilizers include nitrogen, which is a nutrient most fungi adore. Before applying fungicide to your lawn, feeding it first will ensure there is sufficient nourishment. This will promote fungus growth, which will be an issue for your lawn.

Can foliar fertilizer be mixed with fungicide?

Yes, foliar fertilizer can be mixed with fungicide. A foliar fertilizer combined with a fungicide application can result in reduced application costs, better disease suppression and nutrient stimulation, and greater flexibility in handling crop reactions to environmental conditions throughout the growing season.

How long does fungicide take to work?

Fungicide can take anywhere from a few hours to a few days to work, depending on the product and the severity of the infection. It’s important to read the product label carefully to make sure you’re using the product correctly and getting the best results.


Is the question “can I apply fungicide and fertilizer at the same time?” running still through your mind? Hopefully not.

In case, you’re feeling hesitant about your decision regarding the simultaneous use of fungicide and fertilizer. It’s better to consult with an expert.

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Andrew Flintoff

Andrew Flintoff is here! A well-known gardener and a published author. I have dedicated 17 years of my life to gardening and plantation work. to reveal my expertise, I created an online reading store where plant lovers can shop and read A to Z about gardening for FREE. Stay tuned to know more about me.

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