neem oil for cannabis

Neem Oil: The Organic Pesticide Of Choice For Cannabis

Neem oil can act as both a preventative tactic and cure for a number of insect and fungus problems. It doesn’t affect friendly insects and acts as a growth tonic that keeps marijuana vibrant. Neem oil is a must-have for the serious organic cannabis grower.



Neem oil affects a wide variety of insects and plays an important part in an organic pest and pathogen management program. Sometimes, it appears as a deep green or mustard yellow, dark red, or pale green colour depending on the region and the extraction method used.

The neem tree grows prolifically on the Indian subcontinent. It is prized for the powerful effects of the concentrated triglycerides and triterpenoids contained within its oils. Neem oil is pressed from the seed and fruit of the neem tree and has been used horticulturally and in Ayurvedic medicine for centuries.

The list of benefits of neem oil for the human body are quite astounding. Those interested in natural medicine will really find some interesting uses. To this day, neem soaps and cosmetics are still produced and preferred in India.

Neem Oil


The organic cannabis grower will find the benefits of neem oil to be a pest and fungus-free garden. Neem oil remarkably only targets bad bugs in your garden and leaves good bugs alone. A regular application will suppress spider mites and white flies, fungus gnats, and nasty nematode infestations. Ladybugs and butterflies, bees, and earthworms all remain unaffected.

Regular application also suppresses a number of other pathogens that can affect cannabis. Powdery mildew and rust, rose black spot, and other fungi endemic to humid and still conditions cannot take hold. Neem oil can also be watered into the growing medium to prevent or control root rot, while acting as a mild growth stimulant.

The application of neem every ten days acts as a prophylactic measure for pests and pathogens. Prevention is always the best policy. If there is not an active harm prevention policy in place, an infestation of some kind can occur. In this case, neem oil can also be used as a direct pesticide.

Examples Of Use:
  1. Removing the webs of spider mites, then spraying with neem will cure an infestation and return vigour to new growth.
  2. Fungus gnats are more difficult to control as they swarm, but leaf damage is far less with neem oil as the leaves become inedible. Used in conjunction with sticky strips, gnats can be brought under control quickly.
  3. When rinsed through the growing medium with water, neem destroys bad nematodes and makes the bodies bioavailable as nutrients.
  4. Aphids succumb quickly to neem oil, but it will not harm overfed lady bugs.
  5. With one application, leaf miner infestations disappear overnight.


How to mix 100% first press neem oil:
  1. 1 teaspoon of neem oil per litre of water. Neem oil is temperature sensitive and will solidify into neem butter or jelly at lower temperatures. This does not harm the oil; in fact, chilled neem will last much longer. A water bath of 30°C will return it to its liquid form for easy measuring.
  2. Warm water. It is always preferred to use warm water when mixing, then waiting for it to cool. The neem remains a liquid longer, and the surfactant emulsifies more efficiently. Use warm, not boiling water as some beneficial compounds can degrade.
  3. 4-5 drops of surfactant. Neem oil is hydrophobic on its own, and a surfactant needs to be used when mixing it with water. Standard liquid dishwashing soap, preferably non-phosphate, does a perfect job. Literally only use four or five drops per litre.

Once mixed, use an atomiser or one-hand pressure sprayer on the finest mist setting possible. Mist the top and bottom of the leaf surfaces. Turn plants 360° where possible to ensure complete coverage. When applied once every ten days, plants will have an invisible armour against pests and fungi.

Avoid using neem three weeks before harvest. The lingering oil can affect final flavours. Although, it would be very bad luck to have something go wrong in the last three weeks.

Used regularly during all growth phases, neem plays an important role in maintaining plant health. First, as pest and pathogen prevention. Secondly, as a topical solution if there is an infestation. Neem is an essential addition to any organic cannabis garden.

Neem oil controls over 400 different insects and a number of pathogens that can affect cannabis. Don't put up with pests any longer by purchasing neem oil.

Neem oil, the organic wonder treatment for cannabis

Neem oil is impressive stuff, and in this article, we’ll teach you how to mix the perfect solution for almost all cannabis pest problems. Neem oil won’t completely get rid of your pests, and you shouldn’t believe anyone who tells you their solution will. What neem oil will do is help you keep the pest population’s impact to a minimum without harming the beneficial organisms. That way, you can keep a balanced ecosystem in your farm.

What is neem oil?

Neem oil is derived from the Neem tree. It has been used in India for centuries and has become the de-facto treatment for organic farmers all over the world. Made by pressing the oil out of the seeds and fruits of the Neem tree, this stuff is a pure vegetable oil that has all the advantage of the tree’s natural pest resistance.

What does neem oil treat?

Neem oil can impact a wide variety of pests, over 400 different insect varieties as well as most fungus. The best part is, it protects against the neem tree’s natural enemies but doesn’t seem to harm more beneficial organisms!

Protects Against Pests

  • Spider Mites
  • White Flies
  • Aphids
  • Thrips
  • Fungus, Molds & Mildews
  • Caterpillars & Moth larvae
  • Snails & slugs

Doesn’t Harm Beneficial Organisms

  • Ladybugs
  • Bees
  • Butterflies
  • Earthworms
  • Birds
  • Mammals
  • You

How does neem oil work?

Neem oil doesn’t directly kill pests, like most chemical-based pesticides. Instead, applying it creates a hostile environment for reproduction and depletes the population over time. The oil enters the insects and interferes with insects reproductive system and the oily coating on the leaves impacts egg viability. The whole environment becomes toxic to the pests, and after a few generations of low birth rates, the population collapses.

How long does it take to work?

You should start seeing improvements after the first application, but it generally takes several applications over a few weeks to get the problem completely under control.

Will neem oil completely get rid of my pests?

No. These pests have evolved over millennia to be diverse and resistant. The most costly and caustic commercial chemical treatments won’t completely eradicate a pest and neither will neem oil. If it can’t safely be done, then maybe complete eradication shouldn’t be the goal of a pest treatment, but instead, we should strive for achieving a balance.

Neem oil won’t completely get rid of your pests, and you shouldn’t believe anyone who tells you their solution will. What neem oil will do is help you keep the pest populations impact to a minimum without harming the beneficial organisms. That way, you can keep a balanced ecosystem in your farm.

How do you use neem oil?

Neem oil is typically applied as a topical foliar spray that is a mixture of warm water, oil, and soap as an emulsifier. Coating as much of the surface as possible is essential. For mites and other insects, it is doubly important to cover the underside of the leaf, since that’s where they hang out. Its almost impossible for them to attach an egg sac to the oily surface.

You can apply any time of day, but I like to apply just before light out so that the oil can sit on the leaves longer.

How often do you use neem oil?

Spraying your plant once a week is a great way to prevent pests. If you have an active pest problem, you should spray once every other day until the population is under control.

How do you make a neem oil spray?

What you need

5ml Neem Oil: – I use pure, cold pressed oil.

2.5ml Soap: Oil and water don’t mix, so you need soap to bind the spray together. I use Dr. Bronner’s mint soap since it’s organic and the strong mint brings its own beneficial anti-pest properties. Any liquid dish soap will work as an emulsifier.

1 Liter Hot Water: You will need to keep the spray warm while using since the solution will separate as it cools.

1 Liter Spray Bottle: Any clean spray bottle will work.

These ratios are for pure, cold pressed neem oil, Consult your neem oil label for exact proportions for your product.

Step 1: Warm the neem oil

Neem oil is so thick that it’s almost solid at room temperature so you will need to warm it before use. Run hot water over the sealed container or put in a bucket of hot water until it is warm enough to pour.

Step 2: Mix together

Fill the spray bottle with hot water and, once the neem oil is pourable, add neem oil and soap, Replace the spray bottle lid and shake vigorously for a full minute.

Step 3: Apply

Spray all surfaces of the plant until they are dripping with oil. Pay special attention to the undersides of leaves and at the base of the stems.

Is there something stronger?

If the infestation is particularly severe or you want to take a more aggressive approach, there are very effective ‘kill-on-contact’ organic solutions out there. These are generally made with a combination of neem, rosemary, mint and other oils. We recommend that you only use products that are specifically formulated and tested on cannabis, as we’ve documented some bad results with commercial household organic solutions.

We have had success with Bonide Mite-X spray treatment. It’s an organic solution made of botanical cottonseed, clove, and garlic extracts and works as a broad spectrum pesticide which eliminates a wide range of insects including spider mites, aphids thrips, broad mites, russet mites, and whiteflies. Unlike with neem oil alone, spider mites die on contact. Eggs are suffocated within 12-24 hours.

Can I get a premade spray?

If you want to buy something, you can bet that someone wants to sell it to you, and this is no exception. There are some good solutions, but they can be a bit more costly than mixing your own.

Where can I get neem oil?

We recommend Dyna Gro’s pure, cold pressed oil, but any cold-pressed neem oil with work great. You can find neem oil at your local gardening center or online.

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Neem oil, the organic wonder treatment for cannabis Neem oil is impressive stuff, and in this article, we’ll teach you how to mix the perfect solution for almost all cannabis pest problems. Neem