How often to spray neem oil is a notion to go forth when spraying outdoor and indoor plants is something you all should know about. Cold-pressed bone neem oil works as a pesticide against most household bugs like aphids and fungus gnats.Spray Neem Oil

However, it can only be used once or twice weekly for several reasons. Find out the most suitable schedule for applying neem oil in this comprehensive guide.

How Often to Spray Neem Oil on Houseplants?

Spray neem oil on houseplants once or twice weekly to eliminate pest attacks or mild fungal infections. In order to prevent potential infestations by soft-bodied bugs or common fungal infections, spray once every second or third week to give it the right frequency.

– Foliar Sprays

Foliar sprays can be used only once or twice within a week, depending on the condition of the plant. You can apply it twice a week in case of a very acute fungal infection or a prolonged pest infestation. Using neem oil more than this is not safe because the plant will not be able to tolerate it.

Even when it is diluted as specified, spraying this oil will coat the whole plant in a thin layer of oil. These oil droplets take three to four days to break down on the surfaces of leaves and stems.

You should also look into the matter of how spraying more than twice a week will lead to oil droplets forming a very thick layer over plants. The plant will either get burnt if the oil heats up or have difficulty breathing because of blocked pores.

– Soil Drench Sprays

When using neem oil as soil soaks, do it only once every two to three weeks. Once every two weeks should be sufficient for active pest problems under the soil near the roots. For soaks given for preventative measures, once every three weeks is adequate.Soil Drench Sprays

This is because a lot more oil solution is poured over the soil as compared to leaf sprays. It is also a great idea to consider going for only lightly misting the entire plant with the oil solution in leaf sprays.

In a soil soak, you can pour three to four cups of oil and water mixture around the base of the plant. Such a large amount of solution will continue working for at least two weeks before re-application is needed, so make sure to get the right kind when you check where to buy neem oil from.

Are there Different Frequencies of Spraying Different Types of Neem?

Yes, there are different frequencies for spraying different types of neem oil. When it comes to the homemade mix, you can spray it once every week; on the contrary, the commercial neem oil soak should be sprayed once every two weeks.

Different types of neem oils used as plant sprays include organic oil, cold-pressed and raw oil, and hydrophobic oils; hydrophobic oils have the majority of their azadirachtin compounds removed to make it far safer to spray over the leaves and flowers.

– Make Your Neem Spray

If you can source organic neem oil from a trusted home and garden shop, it’s easy to make your own spray. When you make your mix, you must spray on the plant once a week, for different purposes, and when the intensity of the case is too big, you can go ahead and spray twice in the same week.

What you need to do is get some 100 percent natural oil might be too strong for the plant leaves, but with this, you should only use one tablespoon per gallon of water dilution will be needed. We all know that oil does not mix well with water and needs to be broken down first, and this is why you must be keen on the purity of the oil that you have and how it can harm when not diluted.

The puree oil is made from the seed grains of the neem tree; if you are wondering what is neem oil made of. It is obtained by cold pressing the seed kernel to extract this oil that is then used to kill houseplant pests like spider mites while avoiding killing beneficial insects.

As you mix it in, now you must add some liquid dishwashing soaps, because it will come in handy. Mix both liquid soap and oil equally, then add both in water. You will notice how easily the oil mixes with water without separating oil droplets. This spray is supposed to be used sparingly on the plants but rather just once per week.

– Commercial Neem Oil Soak

When it comes to commercial-grade neem oil, you should be aware that you must spray it on the plants once every two weeks, because it has been diluted but contains a strong agent as well. It will be effective when you are tackling the pests away, which is why taking the right measures and spraying on them once every two weeks is a great choice, or even further.Commercial Neem Oil Soak

Most manufacturers sell 100 percent authentic and old-pressed raw neem oil for soil soaks. This is meant to be poured over the soil directly on the roots. Once in the soil, it becomes a systemic pesticide absorbed by the plant’s vascular system.

Azadirachtin is the active ingredient in this oil that disrupts the life cycle of and kills pests. Azadirachtin stays in the plant’s vascular system for about 22 to 24 days. During this time, the plant can fight off sap-sucking pests like aphids and mealybugs by itself.

Most neem oil sprays available are classified under hydrophobic neem oil insecticides. They come prepackaged in emulsified form and only need to be added to water in the quantity specified by the manufacturer. Some come in plastic bottles to which water is added and used to spray plants.

Some manufacturers are even selling ready-to-use neem sprays that need no extra effort on your part. All you need to do is order one of these and start spraying as specified by the manufacturer. Ensure that the manufacturer sells authentic products that have passed your state’s quality control measures.

When Should You Not Spray Neem Oil on Plants?

You should not spray neem oil on plants when they are younger than two months old. Spraying too often and during the daytime is to be avoided. Some plants cannot tolerate this oil at all, like herbs and carnivorous plants.

– More Than Twice a Week

Do not apply neem oil more than twice a week at any rate. Doing so will not cause the pests to die faster but might kill your plants, so be sure that you don’t suffocate the air-pores of the plant’s leaves, as it can harm the photosynthesis processes.

Each oil spray takes around three to four days to dry out entirely from the surface of the plants. If you spray too often, the plant will get suffocated and might get oil burns.

– In the Middle of the Day

The middle of the day is the worst time to spray plants with any oil solution. Even when the oil particles have been adequately emulsified and mixed with water, they get heated efficiently under the bright sun.

These droplets then fry the plant parts over which they are present. You will be causing more harm than good when you spray them in the day heat.

Black and brown burn spots develop throughout the plant within a few hours. In addition, it is a better choice that you wouldn’t start using oil-containing sprays at any part during the day. The time period between nine in the morning till three in the evening is hazardous.

– On Herbs and Stressed Plants

Do not use neem oil on herbs, carnivorous plants, and vegetables with thin leaves, if you are concerned about what plant not to use neeem oil on. Moreover, you should also abstain from using it on plants that are younger than two months or have been recently transplanted. Stop using it on all plants once they begin their flowering stage.Neem Oil

Try any other form of pest control on herbs, and avoid using oil and water sprays. These scented plants like Dill, Cilantro, Thyme, and Parsley hate oil spraying. They might react with leaf wilting, drooping, or the development of burns.

Plants recently transplanted from one pot to another need three to four weeks to establish themselves in their new homes. During this period, avoid using neem oil mixtures on them. Stressed plants will respond like herbs and might even stop growing altogether.

– On Seeds and Young Plants

Neem oil kills seeds and even seedlings of most plants, even in less concentrated spray form. The germination rate of seeds is drastically reduced after oil sprays. This is more true for seeds germinating in a nutritional medium under bright light and high temperatures.

If a young plantlet is sprayed with oil before two months, it might suffer from stunted growth because they still are tender and establishing themselves. The new leaves that will grow might be small in size or wilted. Wait until a plant is at least two months old before using any pesticide.

What Is the Safest Way of Spraying Neem Oil?

The safest way of spraying neem oil is by making a less concentrated solution and using only a tiny amount at a time. Once a spray is mixed, it should be used within six to eight hours and not stored for later because the oil starts to disintegrate.

– Water the Plant First

Watering the plant before applying oil and water sprays has dual benefits. For once, it ensures the plant is hydrated and can withstand the spray. Secondly, it helps the roots absorb water much better because oil impedes water absorption.

– Carry Out Patch Testing

Patch testing before spraying is one of the most essential application tips. Once you have mixed oil with water, spray on a small patch of the plant, like the upper side of a leaf.Neem Oil Application Tips

In such a case, you should be aware and wait for a minimum of six hours to see if any side effects are apparent. If you can wait for 24 hours, that would be even better and safer, and if it needs to be diluted, you should add some more water to decrease the concentration.

– Spray Only as Required

Drenching the plant with the spray from top to bottom is unnecessary. Always use a spray bottle with a small nozzle that releases the spray in mist form. Spray from a distance of about six to seven inches from the leaves and the stems.

In short, do not spray that part again once one particular plant segment has been misted. The most critical place is the underside of the leaves which must be noticed, so you will see how this is where most of the pests hide and then lay their eggs. If flower buds have begun growing, avoid them while misting.


Neem tree oil is among the most potent and effective pesticides. Here is a brief recap on how often it is safe for use:

  • This oil in spray form should be used once or twice a week to treat active infestation cases.
  • Spraying once every third day to prevent pest attacks makes neem oil safe for plants.
  • Any oil concentrate can be used, like Dyna-gro pure neem oil or captain jack’s neem oil concentrate, but it must be diluted with water and insecticidal soap.

Keeping our fingers crossed that this article will help you plan your pesticidal spray schedule much more effectively than before.

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