Neem oil and flowering plants?

What’s the recommendation when using neem oil on flowering plants ?

I know most people will say don’t ever do it but honestly I have sprayed one week up to harvest and I only do that in situations when I think there’s a lot of moisture in the atmosphere in my area or I think there’s a possibility of bugs being an issue late in the game but I’ve never had iel wheel or bad effects from it or bad tasting smoke from doing it… that’s just my two cents and i mix 2 ounces to a gallon of water…



Thanks for the input, I’ve used it just as you’ve said and it’s been fine, I’m fighting septoria so I don’t have an alternative.

I’m trying to find out if there’s any downside to it, neem oil says it can be added to the feeding water so I’m hoping spraying during flowering is OK ?

Anyone else use it too?

One possible thing I’ve noticed although I’m also using baking soda spray (Need oil & baking soda one × week) the buds have been darker ?

I’ve had OG Kush and Northern Lights, both were Second Generation and they’re nothing like their mother plant, both are much darker

How ya doing my friend ?

I believe this is what your looking…if not let me know I got more on this neem oil.


Neem oil is a highly effective and 100% natural pesticide, extracted from the seeds of the Neem tree in India. Neem oil is non-toxic to animals or people. Neem is systemic.

Neem oil is most effective when used as a preventive, meaning that you spray every crop regardless of whether or not you see a pest.

Many growers seem to be put off by its oiliness, finding sprayers clogged and plants left coated in oil. The solution is to get the oil broken down and suspended in the water, then we can get it onto the plants.


1 litre warm water
8ml cold-pressed Neem oil
5ml liquid soap

Note: If your Neem oil appears solid and/or cloudy it is most likely too cold. Run the bottle under warm water for a few minutes until the Neem oil is easier to work with. Shake it well.
8ml Neem + water
8ml of Neem oil + 1 litre of warm water

you can see that the oil and water are completely separated…

8ml Neem, water and 5ml soap

8ml of Neem oil + 5ml of liquid soap in 1 litre of water.

NOTE - you may have to add more or less soap, depending on the strength of your soap. When you can see soap bubbles youve got it right.

Shake this in your sprayer, it should make a milky-white liquid, with no oil floating on top. Leave it to settle for a few seconds. If there are any oil droplets floating on the top, add a little more soap, drop by drop, (keep shaking) until the oil is gone. Dont be surprised if you have to add more soap than I did. Now you are ready to spray.

Spray everywhere, especially under the leaves where critters hang around. Get those plants dripping wet. Keep shaking while you spray.

IMPORTANT - you must repeat this application every 3 days for at least 2 weeks (3 weeks if you want to be 110% sure)

This is important because Neem oil doesnt directly kill bugs (amongst other things it stops them from reproducing, feeding and molting their skins). So in effect, it breaks their life cycle.

This means you need to spray for at least the length of one life cycle, which for spider mites in ideal conditions (like most growrooms) is around 2 weeks, sometimes a little longer.

I use this method for the first 2 weeks of 12/12. It was taught to me by a professional grower of 20 years experience. He also uses this recipe as a soil drench (Neem is systemic and therefore there is no need to spray if soil drenching)

I have used it as a foliar spray for about a year now and have had no problems with mites or any other vermin, large or small. Skeptical friends have also been won over to this system.


If you are facing an infestation emergency, you can add Pyrethrum to the above mix. I challenge any nuclear-proof insect in the world to survive the twin pain of Neem and Pyrethrum.

Notes on Ingredients:

Cold-pressed Neem oil has much higher levels of active ingredients and is well worth the money. A good place to find this stuff is from a Pharmacy that stocks herbal remedies. (It is used as a treatment for head lice.)

If your Neem oil appears solid and/or cloudy it is most likely too cold. Run the bottle under warm water for a few minutes until the Neem oil is easier to work with. Shake it well.

Liquid Soap - plain unperformed, boring liquid soap. Personally I don’t let that stuff anywhere near my plants, but many do, and if you’re one of them you may find you need less than if using liquid soap. Experiment a little when you shake the mixture. Plain liquid soap is much more gentle than washing-up detergent.

Pyrethrum is extracted from Chrysanthemum flowers. It is a highly effective and 100% natural insecticide. It is also one of the safest, bearing little threat to mammals. Pyrethrum degrades quickly once sprayed.

Editors note: Liquid soap is similar to Safers soap (a fat based liquid soap mixture). Safers suffocates and dessicates (dries out) insects. Works good, but can also clog leaf stomata, so a follow-up spray of water is required.
Related entri


@garrigan62 …that’s just what I wanted ! :thumbsup: -thanks

Well maybe not just what I want because it doesn’t talk about using neem oil in flowering ?

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I couldn’t agree more, great post.

I like the idea so much from what you’ve said and what I’ve learned similar from others that I decided to find a way to make it work better. I found a way so that you need a lot less Neem oil or any other menthol plant extract. I make my own soap from the oil using potassium hydroxide, alcohol and a steam vaccum distillation process. What comes out the other end takes very little to solve the problems and leaves no oily film.

I got lucky and I used hard work, now we have no pests of any kind.

Thanks for the great posts.


Great info.

Thank you thank you 4 creating this post! Battling pests right now :slight_smile:

Great post, can you tell me more about the soil drench?

what if I dont use soap?

Does it matter when you apply it ? indoors/ outdoors beginning of light cycle or dark cycle morning or night?

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Great information here! I personally use a non-preservative yucca extract for an emulsifier as opposed to soap… you can also add in a silica foliar Spray inaddition to the neem and get a little added strength and some light foliar feeding with this mix. I didn’t cite any brands not knowing if it’s allowed or not… I personally use this spray throughout the entire life cycle, as the yucca makes for an excellent root drench due to its emulsification properties and has some great benefits for seedlings and clones as well.

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I personally try and spray very early at sunrise or late sunset to avoid foliage burning from droplets… I’m not much help as far as indoor procedures

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Thank you! @Loudaboutit that lines up with what I hear about indoors ( avoid light burn )

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Leaf Slick? lmao I use it from time to time but wasn’t quite sure if it would emulsify neem?

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I personally use yucca schidigera extract, cold pressed neem, and a product called protekt…
Spray Recipe: 1Tbs Neem, 1 Tbs ProTekt, 2 Tbs yucca in 1 gallon room temp distilled water, shake well, put in spray bottle and go. Shake often while using, store in shade or cool place, one month life expectancy on formula.
The yucca adds some other benefits that soap cannot… since it’s a hardy desert plant, the extract lends some of these resilient properties to the cannabis, as well as emulsifying the neem oil. :wink:


Foliar spray with silica and neem oil and be light on the soap if your late in flowering, especially if you’re close to flushing and harvesting. Remember to foliar spray with the lights off for indoor and for sun grown early mornings or late evenings or cap your structure for GH or LD. Thanks to the BUD GODZ happy harvesting! 4:19 got a minute!

Yucca is great to mix in with them neem oil as well! YEEEEEEEE :money_mouth_face: :money_mouth_face: