How To Use Neem Oil to Kill Spider Mites

Spiders are an uncommon pest with a body that resembles a tick but is capable of forming messy webs resembling spiders. Neem oil is a natural insecticide extracted from the seeds of the neem tree. In concentrated form, it has a thick, pungent sulfurous smell, but when properly mixed with water and a mild organic emulsifier, it’s a safe and effective insecticide for home and garden plants. Below, you’ll find a complete guide to making a neem oil spray and using it on indoor and outdoor plants.

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Are Spider Mites Really That Bad?

What makes spiders a major garden pest is their ability to reproduce exponentially. Within a few days of hatching, a female spider can lay 8-20 eggs per day and live up to 3 weeks. This means that a single female spider if left undisturbed, could theoretically produce more than 300 eggs by the end of her life. For plant lovers, that’s a scary statistic.

Not only do spider mites reproduce quickly, but they also attack more than 200 plant species and have the ability to quickly spread from one plant to another, and from property to property.

This suggests that you have to start attacking spiders the moment you see them. Killing 1 spider is easy. Killing thousands requires more time and attention.

How Do I Know If I Have Spider Mites?

When the spiders attack the plant for the first time, they leave a slight stippling effect on a few leaves. Here’s how you’ll know if you have spider mites in your home or garden, so keep an eye on the leaves whenever you buy or care for your plants.

Unfortunately, determining if you have spiders is only the first step. Next, you have to ask yourself the question, “How bad is the infection?”

I mention this because, unlike some bloggers, I don’t advocate a one-size-fits-all approach to combating spider mite infestations. As I mentioned in this article, you must take into account the extent of the spider infestation and damage before developing a treatment plan.

(When it comes to fighting spider mites, you need a treatment plan. You can’t simply spray around and hope for the best.)

Simply put, the sooner you get infected, the better off your life will be. The more severe the infestation, the more time it will take to stop the spider from spreading.

What’s Neem Oil?

As mentioned above, neem oil comes from the seeds of the neem tree. The neem tree (Azadirachta Serrata) is a fast-growing distant relative of the redwood tree, and although they originated in India and Southeast Asia, they are now ubiquitous in Asia, Africa, and South America.

These trees produce grape-like green edible fruits whose seeds, when harvested, dried, and pressed, produce an oil that has both medicinal and insecticidal value.

How Much Does Neem Oil Cost?

How much you end up spending on a good neem oil spray will depend entirely on whether you prefer to buy a pre-made spray or make your own.

Pre-made sprays typically cost $10 for 24- to 32-ounce bottles, which means you’ll pay $10 everywhere. 31 to USD. 42 per ounce.

Why Should I Use Neem Oil?

Neem oil is an effective insecticide for two main reasons:

First, the neem tree produces a natural compound called azadirachtin in its seeds. Azadirachtin is biodegradable and virtually non-toxic to humans and pets (as long as it is not ingested), but it can cause hormonal problems in a variety of insects, preventing them from completing their life cycles.

Second, when insects are attacked with a neem oil spray, the insects are covered with a slight oily film that hinders their function. Depending on their stress resistance, this alone can kill a variety of soft-bodied pests (aphids, cucumber beetles, thrips, whiteflies, etc.). It also kills bugs, such as leaf-footed and squash bugs, when the bugs are in their nymphal stage, and therefore do not yet have an adult exoskeleton.

A side benefit of spraying spider mite-infested plants with neem oil is its bactericidal properties. It breaks down quickly in sunlight – it can damage the foliage of plants if used in the morning and early afternoon when the weather is hot – but there is evidence that it may be effective against plant blight, powdery mildew and other Fungal diseases help.

How To Use and Mix Neem Oil To Kill Spider Mites

As with the soil soak, you only need three ingredients.

Begin by emulsifying the water in the same way as the soil soak, then add four teaspoons of clarified neem oil.

Use a spray bottle to coat the entire plant, scouring out each crack, and making sure the underside of each leaf.

Any encased nymph or adult spider will die quickly, although it will not kill the eggs.

You will need to reapply every 2 days for 14 days, or until the infection clears up. After that, you can use a foliar spray every 2 to 3 weeks as a preventative measure.

When Should I Apply Neem Oil?

If you’re going to spray neem oil on your plants, you need to be very careful and thoughtful about when, how, and how often to apply it.

Neem oil should be used in the late afternoon or early evening, usually between 6:00 pm and 8:00 pm. If applied too early in the day, the oil can damage the leaves of the plant. If applied too late, visibility will be limited, increasing the chance of misapplying.

I prefer spraying the plants with neem oil as late in the day as possible while still taking advantage of the visibility, which means I can’t recommend setting the time as the sun will set at different times depending on the season and geography.

But it’s easy to figure it out on your own. Just make a note of when the sun goes down and set off an alarm 30 minutes in advance to remind you to get outside and spray your plants before it gets dark.

Don’t underestimate the importance of alerts, especially when you’re battling spider infestations. If you miss an application, you’re just giving the spider more chances to reproduce and continue to destroy your plants.

How Often Should I Spray My Plants?

If you want a detailed overview of my treatment plan to stop spider mite infestations, see my article “Can Plants Recover From Spider Mites?” What you need to know.

But here is a simple sketch of my approach:

For mild infections, I spray the plants daily for 4-7 days with insecticidal soap spray (up to 6 days) and neem oil spray (1 day).

For moderate infections, I get more aggressive as they get out of hand quickly. I sprayed my plants 10 days in a row alternating between insecticidal soap spray (8 days) and neem oil spray (2 days).

For late infestations, I trim all dead leaves, then spray the plants for 16 days, alternating again with insecticidal soap (12 days) and neem oil (4 days). This may be a bit extreme for some, but if you’ve already had a severe infestation, you may have thousands or even tens of thousands of spiders in your garden. To stop the spread of the virus, you need to take aggressive action.

I’ve seen some people recommend spraying neem oil for days on end, but I don’t. I usually spray neem oil every 4 days. When I got rid of the spider mite infestation, I saw the best results when I alternated between soap spray and neem oil spray and took an aggressive approach to application.