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.