Neem oil is the answer to many needs of gardeners. Do you need a fungicide, an insecticide, an antibacterial for your plants, Houseplants, flowers or crops but you don’t want to use chemical products?
Don’t worry, Mother Nature already has the solution: neem oil of course. Its popularity with gardeners and amateurs alike is growing very fast, and for good reason.
Neem oil is natural oil extracted from Azadirachta indica, or Indian lilac, and it works perfectly well as an insecticide, a fungicide and an antibacterial remedy for plants. It is fully natural and perfectly safe for your plants. Compared to synthetic products, it has many advantages, and it is safe to Humans too as long as you don’t ingest it.
So, if you want to know how it is made, when and how to use neem oil on plants , and, maybe above all, how to use it safely, you have come to the right place because this is exactly what we are going to see.
What Is Neem Oil?
Neem oil is the oil obtained by pressing the seeds of Azandirachta indica, also called neem, Indian lilac or neemtree. It is an evergreen plant that grows very fast and tall, which makes it very profitable to grow.
As one of its names suggest, it comes from the Indian Subcontinent, though it can be found in some areas of the Middle East as well.
Its fruits look a bit like olives, and the trees can be very big indeed; they can grow to be 130 feet tall, which is 40 meters, though most are about half as tall.
Making neem oil is, in fact, not dissimilar to making olive oil; when the stone is pressed, it releases an oil that can be of different colors, from golden yellow, to dark brown, brownish green ore even of a bright red shade. Its smell is very distinctive, and it will remind you a bit of peanuts and garlic combined.
What Is Neem Oil Useful for?
Neem oil has three main properties that you can use to treat your plants:
As you can see, it is actually three products in one. This should already make it climb the top of the list of treatments to have for your plants, outperforming most synthetic products.
What Makes Neem Oil Useful For Plants?
Plants contain active ingredients, what chemists technically call “drugs”; these are the active principles of medicines and not only.
Neem stones contain azadirachtin, a limonoid, which is also an antifeedant, a substance that stops insects from feeding. Basically, insects and pests cannot eat it, so it protects your plants.
There are at least 200 series of insects that cannot stand neem oil, and possibly even as much as three times this number!
But there is more; neem oil affects the hormones of insects. Because of this, they will not be able to lay (as many) eggs and reproduce. Stretching it a bit with a metaphor, we may see it as giving insects “early menopause and andropause”.
The damage to the hormone system of the insects that get in touch with neem oil also thwarts their growth.
This is not all; neem oil kills fungi; this has been known for millennia in India, in fact, it has been used in Ayurvedic medicine to cure skin fungal infections and other ailments since time immemorial. And it is very effective at that too, especially nail fungus.
Finally, neem oil has antibacterial properties. In fact, it contains some isoprenoids that kill bacteria, in your plants and not only.
This is how it can be used for plants, but you may have grasped that neem oil also has great medical properties for Humans and animals too. But this is not what this article is about.
This may all sound a bit scientific, but don’t worry; while it is only fair that you know why and how a product works, we will now focus on how to use, it, when and how to do it safely.
The Advantages of Using Neem Oil
But why should you use neem oil, when there are so many chemical products on the market?
Some of you have already answered this question, and if it is for the reason I suspect, I agree with you…
But let’s look at the advantages in detail.
If these advantages don’t convince you, I don’t know what would. Neem oil is becoming very popular because it is an excellent natural solution to many health problems of your plants.
Using Neem Oil: Safety First
We have said that neem oil can be toxic, but only if ingested in substantial quantities. This does not mean that you should regard it as “poison” with the little skull and bone sign.
There are many products we use every day that you can’t ingest… But there are some safety measures you want to use:
These, you may notice, are the normal precautions you would need to take not only with synthetic products like pesticides etc., but also with normal home cleaning products like bleach etc.
So, while they may look “scary”, they are not, and remember, unless you swallow it, nothing will happen to you
Is Neem Oil Safe for Pets?
But how about if you have cats, dogs or a gerbil and you want to use neem oil? Here’s the good news: neem oil is not actually toxic and animals will just not touch your plants if they have neem oil on it.
You don’t risk seeing your puppy licking up neem oil from a plant, nor even if you put it in a bowl; there’s no worry on that side.
They will just stir away from it. And they can smell it, don’t worry; breathing it has no adverse effects.
Can You Use Neem Oil for Prevention?
You may be wondering, “But if neem oil keeps insects, bacteria and fungi away, can I just use it on my plants as a form of prevention?” I am pleased to tell you that, yes, you can.
Neem oil will work as a preventive treatment for all the ailments and problems it cures.
So, if you think your Philodendron is at risk of attracting pests, you can spray it with neem oil and the pests will not come.
Similarly, especially with succulents and dry loving plants, indoor conditions are often far too humid for them, and they may risk fungal infections. Give them a little spray of neem oil once in a while and you will keep them safe.
In fact, if you grow plants professionally, especially in a greenhouse, it is not at all a bad idea to give them a little spray of neem oil every month or so to keep them healthy.
How Long Will Neem Oil Last on Your Plants?
So, if you use neem oil as prevention, how often should you apply it to keep pests and fungi at bay?
The safe answer is every ten days.The oil will completely coat your plants for about this time, after which, it will start to dissolve.
Of course, this is a general rule, but considering the operation is simple and straightforward, it may be worthwhile, especially of your plants are at risk or if you have a lot at stake.
What Does Neem Oil Quality Depend on?
Neem oil is not all of the same quality, like all products. Good quality neem oil will have a high concentration of active substances, like azadriachtin. But this depends on a few things, including:
The best quality is obtained by cool pressing the stones. This is the same as with extra virgin olive oil, and with most (maybe all) oils. But this is, of course, more expensive.
Still, the good news is that even fairly low quality neem oil will suffice for most plant problems. Very high quality neem oil is more common for therapeutic uses for Humans.
In fact, look up online for high quality neem oil and you will find treatments for many, many health problem, especially skin problems.
So, you can make do with a fairly good bottle of neem oil at a very decent price for your plants, flowers and crops.
Ways of Using and Applying Neem Oil
Let’s get practical now: are there different ways of applying neem oil, and if so, which are they? The answer is that yes, there is not a single method for using neem oil.
In fact, many gardeners have developed their own methods; they find that by “tweaking” the basic methods they find solutions that work well for them.
So, here are the two key ways of using neem oil:
These two methods are different in both the preparation and possible uses for treatment. Still, both are simple and straightforward. Shall we now look at them?
1″: Dabbing Neem Oil on Your Plants
Welcome to the simplest me most straightforward way of using neem oil to treat your plants. This method is more laborious than the next one, but it is so easy and focused that it does have its functions, and we will see which.
Here we go:
As you can see, the preparation is simple but if you have many plants to treat, passing the cloth on each leaf, top and bottom, each branch etc can be a rather slow and laborious process.
Nevertheless, this method is very effective if:
On the other hand, this is not a method you can apply to big plants or large gardens or even large parts of gardens of course. Still, in an emergency, don’t be afraid to use it.
What is more, this is certainly not a method you can use as prevention.
You should keep an eye on your plants after applying neem oil this way; this is only to make sure that the plant gets better and to be read it to repeat the operation as necessary.
2: Spraying Neem Oil on Your Plants
Spraying neem oil on plants is by far the most common and practical method. However, you cannot spray pure neem oil directly on plants.
Actually, in theory you can, but it’s quite hard to spray oil; it offers a lot of resistance when you spray it and it may not come out uniformly. So, what can you do?
The trick is to melt the neem oil in water, but maintaining all the active substances that neem oil is rich in. But here there’s another problem: neem oil does not mix with water, like all oil.
Oil is fat and fat is hydrophobic, which means that it repels water molecules and does not mix with them. I am sure you have noticed it even with cooking oil…
So, what can we do? Simple, mix it with soap water. By the same principle you use to wash your dishes and glasses, you can mix neem oil with water. And here is how you can go about it:
Preparing Your Neem Oil Spray
That’s about it. Don’t worry if the mix falls onto the potting soil or on the ground; it is perfectly safe for your plants…
Now, this method may require a slightly longer preparation but it has many advantages:
If you use this method, make sure you are easy to apply the spray after 10 days or so. The neem oil will have vanished, dissolved and disappeared at about that time…
So, as you can see, neem oil is very easy to use, and it has no downsides at all…
Neem Oil: Is It the “Miracle Cure” for Your Plants?
From what you have read, you may be excused if you believe than neem oil is like a panacea, a miracle cure for most of your plants’ problems. But is it so?
Well, like many organic remedies it is becoming more and more popular by the day… The reason is of course that you don’t need to handle synthetic chemicals, nor will you be dispersing them into the environment if you use the oil of this beautiful plant.
But there is more, it is very easy to use, it is widely available, safe, and – let’s not forget – it treats an awful lot of problems and ailments your plants may have, and it prevents them too!
Still, it does not treat all ailments and health issues;there are some that even neem oil cannot solve, like root rot, some very stubborn pests etc. Having said this, I think it will be hard, in a few years, to find neem oil missing from the cupboard of any organic gardener…
But one thing can treat your plants better than neem oil, yes, and that one is actually free: it is simply called love and tender loving care…
Amber Noyes was born and raised in a suburban California town, San Mateo. She holds a master’s degree in horticulture from the University of California as well as a BS in Biology from the University of San Francisco. With experience working on an organic farm, water conservation research, farmers’ markets, and plant nursery, she understands what makes plants thrive and how we can better understand the connection between microclimate and plant health. When she’s not on the land, Amber loves informing people of new ideas/things related to gardening, especially organic gardening, houseplants, and growing plants in a small space.