I like to use neem oil on my plants because it works as an insecticide and fungicide. But you need to be careful how and when you use it on your plants.

You can put too much neem oil on plants if you apply it several times a week. You can also put too much if you have not diluted the neem oil before use. If you use too much neem oil, it will burn the leaves, may cause them to turn yellow, and even kill beneficial insects.

I’ve written how you can know if you’re using too much neem oil and how much you should actually be using.

How can you know if you have put too much neem oil?

Leaves are getting sunburned

If you put too much neem oil, it will stay on the leaves for a longer period of time. The oil will start to heat once the sun comes up causing the leaves to burn.

Leaves are drooping or turning yellow

The excess neem oil will coat the surface of the leaves and block the pores. This will cause problems for plant respiration.

The leaves will find it difficult to create the required nutrients and they will start drooping or turning yellow.

Will too much neem oil damage plants?

Yes, too much neem oil will damage plants because it forms a coat on the surface of the leaves. This suffocates the leaves and they are unable to produce food.

The excess neem oil will cause the leaves to burn due to the heat from sunlight. If you spray it on the soil, the neem could reach the roots and damage them as well.

Too much neem can be toxic to your plants and cause problems for them. It can also be toxic to beneficial insects and aquatic life.

Neem oil is safe for edible plants as well. But you need to follow the same precautions. You need to dilute it with water and use the right amount. Too much neem oil will harm the plants.

How to clean excess neem oil off plants?

If you have used too much neem oil don’t worry because you can get it off your plant. 

Wipe the excess neem oil off with a damp cloth. The spray water on the leaves so the neem oil can rinse away.

If the plant has been stressed and showing yellowing leaves, you can give it good watering to help it recover.

I’ve written the ultimate guide that will help you water your plants at the right time. It will also help you figure out how often you should be watering the plants.

How can you avoid applying too much neem oil?

Dilute the neem oil before use

The most common cause of using too much neem oil is because it’s not diluted well with water.

If you’re using pure neem oil, you can use 1 tablespoon neem oil in 1 gallon of water. You can increase or decrease the measurements based on how much you need for your plants.

Apply neem oil at the right time

If you have neem oil on the leaves when the sun is out, it will cause leaf burn.

I recommend applying neem oil either early in the morning or in the evening. This will give time for the neem oil to be absorbed and dried out before the sun comes out.

Don’t apply neem oil on sensitive plants

You should not apply neem oil to young plants that may be less than a month old. So if you have just transplanted seedlings, don’t use neem oil on them.

You should also test the neem oil on some parts of the plant before you apply it to all the leaves. This will help you understand if the plant is sensitive to neem oil and you should not apply it.

How to prepare neem oil spray for your plants

Video provided by Eli from the YouTube channel “The Kitchen Garden with Eli and Kate

You can get neem oil in pure form, concentrated form, or a spray. I would recommend using pure, organic neem oil that is cold-pressed.

I would recommend the Harris neem oil you can find on Amazon. It’s cold-pressed, all-natural, and does not contain any chemicals.

The concentrated neem oil and spray may contain other chemicals that are not clearly mentioned on the bottle. 

You can make your own neem oil spray using pure neem oil. Here are the things you need.

  • 100% pure, organic cold-pressed neem oil
  • 1-gallon spray bottle
  • 1-quart container with a lid
  • 1 teaspoon Castile soap
  • 1-gallon clean water

Neem oil does not mix well with water so you need to emulsify it before you can use it as a spray. You can do this using water, Castile soap, and neem oil.

Pour 1 tablespoon of neem oil into the 1-quart container. Add 1 teaspoon of Castile soap to this. Now fill 3/4th of the container with water.

Close the lid of the container and give it a good shake so all the ingredients are mixed well. You should not see droplets of oil floating on top when the emulsion is done well.

Pour this emulsified solution into the 1-gallon spray bottle. Add the remaining water to fill this spray bottle.

You can keep this neem oil spray for several days and use it on your plants. But make sure to shake it well before use as the oil may settle to the bottom.

I recommend only making enough for spraying it on your plants and creating a fresh batch for the next spraying schedule. That way you get a fresh solution every time for your plants.

How to use neem oil spray on your plants

It’s important to spray the neem oil on your plants either early in the morning or in the evening so that the sun does not burn the leaves due to the oil getting hot.

I prefer spraying in the evening because it will get plenty of time to dry. And the beneficial insects would have left so you won’t end up accidentally spraying neem oil on them.

Make sure to wear gloves because neem oil can cause an allergic reaction in some people. And it will help avoid oil from getting on your hands.

Use the spraying can and spray the solution well on the leaves. Remember to shake the can between sprays so that the solution gets mixed well.

Make sure to spray on the bottom of the leaves where pests can hide. Keep spraying the leaves till the solution drips from them.

You should spray the neem oil solution just once every week or a couple of weeks. Don’t spray it if the plant is stressed or on young plants.

You can also spray the neem oil solution on the soil to get rid of fungus and pests.