I'm searching for the definitive guide to mixing pure neem oil. There has been a lot of discussion around things like water hardness, pH, temperature, emulsifier, etc. over the years, not all seems to be relevant to successfully mixing pure neem for application with an airblast sprayer. I'd love to hear from folks who have tried and failed and others who feel like they have it all figured out (and anyone else in between). This is an important topic as the season is just about to get started so anyone (and everyone) can avoid problems.

Here is the approach I have used more/less successfully over the years:

1. Warm pure neem to > 60F so it thaws thoroughly prior to any mixing activities.
2. Using a paint stirrer (on a drill for easier mixing), mix 1 oz pure neem + 0.5 teaspoons of organic dish soap or soap nuts (or other emulsifier) for every gallon of water you will be mixing into. E,g., i) 1% neem solution = 1 gal neem per 100 gallons of fresh water. ii) 1 gal neem = 128 fl oz. iii) Emulsifier needed = 128 x 0.5 teaspoons/ounce neem = 64 teaspoons = 10 ounces emulsifier. iv) A 2% solution would be twice these rates.
3. So, 1 gal neem + 10 oz emulsifier, mix thoroughly - add slowly to 100 gal fresh water in spray tank WITH agitation.
4. If the water is cold, use a little warm water (DO NOT USE HOT WATER - it can destroy the properties of the oils) to thoroughly emulsify the oil and then add the remaining water and agitate well. Make sure the oil is completely emulsified before spraying.
5. If there is oil floating on top add more soap or emulsifier as needed.
6. Spray as you would any prepared materials.

CAVEAT - If you have hard water, I would add something to soften the water (not salt) like Choice or an acidifier like citric acid. I know there has been some debate over the need to use a water softener and this is one of my primary reasons for this post. However, knowing what i know about how clingy hard water can be, it seems you'll get better mixing if you can reduce the hardness of your water below 75ppm, and even better lowering it below 50ppm for truly soft water.

I don't claim this is the definitive guide, though it is what's basically posted in Ahimsa Organics web site and that many of us have used in the past. I am very interested to learn (as would others, I'm sure) what successes and failures other have found in their experiences with Neem.
Thanks to Ahimsa Organics for some of the basic recipes and caveats embedded in this post.

Mike Biltonen, Know Your Roots
Zone 5b in New York

You forgot the dance. Growers absolutely must do the 'neem dance' while mixing to perfect the emulsification.

Pure humor to go with pure neem!. I love the idea of a consolidation post, Mike, to bring a range of complications and solutions to the fore.

My two suggestions would be:

-- Provide the math for a 0.5% concentration as that's the rate for general foliar application. This requires 1/2 gallon of seed oil per 100, to which I add an overflowing quarter cup (16 teaspoons) of biodegradable liquid dish soap.
-- Use two parts neem oil to one part karanja oil (70/30) for synergistic advantage, ease of mixing, and cost savings

Lost Nation Orchard
Zone 4b in New Hampshire

How about doing that in metric???
You are playing with ounces, gallons, teaspoons. And Michael even adds cups. Really, one has to be pretty good in maths to follow this.

Jolicoeur Orchard
Zone 4 in Quebec
Author, The New Cider Maker's Handbook

Claude,
I trust your math. I've read your book. Besides those of us south of the border rejected the metric rationale a long time ago. we look our irrational ounces, Fahrenheits, and inches.

Mike Biltonen, Know Your Roots
Zone 5b in New York

So, after trying to more deeply understand mixing and using neem, and after a small-scale disaster, I have the following questions in a follow-up to my original post and Michael's neem dance suggestion: There aren’t any specific parameters available (that I am aware of) that talk about

i) optimal temperatures - Usha recommends something in the 105F range, but no hotter and certainly not luke warm. Thoughts? At what temp does neem breakdown, karanja?
ii) optimal pH - influences and is influenced by pH. 6.5? 6? More....
iii) optimal water hardness - 100, 75, 50 ppm?
iv) optimal emulsifier rates - this seems to be a bit sorted out, but I am sure depends on the other water characteristics and the eumulsifier
v) optimal (if any) rates of fish oil or karanja. Michael has answered the karanja question, but what about fish oil?

Any details or personal experiences people can provide are greatly appreciated.

Mike

Mike Biltonen, Know Your Roots
Zone 5b in New York

I second Claude's request for a metric dance, I mean, version of the mixture. I work in liters and kilos and all the many variations thereon and it drives me near crazy to hear (mostly former brewer types I think) talk of barrels as a unit of volume. I understand that is 31 gallons in modern parlance, about 117 liters, but because I age some of my cider in used wine barrels I always have to pause my discussion and brain when someone mentions barrels to think about the context--wine barrels come in different sizes depending on the alcohol inside--anywhere from 225 liters to 300 liters.

Beyond that, thanks for these ideas, in whatever formula you provide them--super useful.

Wheat Ridge, CO, Zone 6a (2018)
Golden, CO, Zone 5b (2018)
Crawford, CO, Zone 6a (1905)
Lewis, CO, Zone 6a (2017)

We are having issues with neem emulsifying and have followed Michaels recipe. As for soap, I seem to recall it being mentioned in a video of Michaels somewhere that stated that Dr Bronners pure Castille soap isn’t as concentrated as say Seventh Generation. Can I ask members to comment on what soap they are using? I’m having to use an aweful lot of soap. The garden neem I have recommends 1tsp neem per litre to 1tsp castille soap. It is pure cold pressed raw neem.

On another note, is pure cold pressed raw neem oil sold as cosmetic grade good? I’m hoping to purchase a gallon of the oil that Michael uses but currently, my finances not in the best of shape. I’m also in western Canada so finding neem is a challenge. It’s almost $200 a gallon landed.

Thanks everyone!

Editor's Note: Check out Sourcing Pure Neem Oil in Canada for availability north of the border. Another thread entitled TerraNeem makes important distinctions about grades of neem. A new thread on using neem with low azadirachtin content (cosmetic grade) would be interesting.



Edited 1 time(s). Last edit at 07/01/2019 02:00PM by Michael Phillips.

I had a lot of trouble using hard cold well water. The neem would congeal and coat the inside of the spray equipment. It was difficult to remove. I have since connected a garden hose to a basement sink and use warm water that has been through the home water softener in the spray tank. It has made a world of difference.

I recall from an earlier discussion that at least some folks did not think there was any problem using softened water, though I was concerned about the salts. I have been doing this for two years with no observable harmful effects, and am a much happier camper at cleanup time, and also think I am getting most of the neem on the trees instead of lining my spray tank and hoses.

Turkey Creek Orchard
Solon, Iowa (zone 5A)

We found a solution! We changed from dr. Bronners to Seventh Generation (biodegradable). Amazing difference. Yes it's warmer out but the emulsification was so much better than cleaning was easier as was spraying. For 100L we used 1/2 cup. I tried sprays with 1/3 cup and less and it wasn't quite enough and adding more after the fact doesn't do the same as emulsifying early on.

Hopefully that's not too much soap. I've made lots of insecticidal soap that has much more soap but it's generally not a soil level.

Anyone chime in on this?

What do folks have to say about Neem oil spray clean-up? I know I've seen something on this in another thread, though I'm not sure where right now.

I am using an old 100 gal Tecnoma airblast sprayer. In the past I have used the various clarified extracts not recommended on this forum, and will be switching to 100% pure this season.

Any experience or methodologies for keeping spray equipment, large or small, clean and in good working order with regular pure neem sprays?

Center Valley Orchards
Washington State - Olympic Peninsula

totally in sync with you on this cleaning the tank after' headache. It had not occurred to me that my hard well water was the cause or the pond water either for that matter. I make up 50 gal (200L)tanks mostly with pond water and have a hellufa mess after inside the tank. Creamy foamy oily crude, and agreed, I wonder how much that translates into lost material not sprayed. I can use rainwater if I plan ahead. Will report back on that.
Note to file: if you ever buy a tank sprayer make sure it has been designed for thorough clean out. Mine from a reputable shop in St Catharines (Rittenhouse) has no access to the interior except the main 8" (20cm) twist on lid. Sure it will drain through a ball valve but make sure it's at the lowest spot in the tank.

Old 99 Farm and permaculture site
Dundas ON 5b



Edited 1 time(s). Last edit at 04/14/2021 04:33AM by Ian Graham.

The folks at Whiffletree Nursery suggest cleaning out the sprayer with a vinegar solution. Are you in Dundas county or the County of Dundas? I'm between Ottawa and Kemptville.

Colin Lundy
Colonial Inn Orchard
North Gower, Ontario
Zone 5a (Canada)
Zone 3b (USDA)

Just a quick note that I've found using a jar to mix the neem + soap (Seventh Gen. also works great for me), + a bit of warm water if need be, to be much easier than stirring. Plus, if you use 2 jars, you can shake them like maracas while you dance. Or re-enact your favorite scene from Coyote Ugly.

Earthworks
Zone 7a in West-Central MD
Non-commercial, ~100 fruit trees, dwarf to MM106

I also hook a hose up to a sink and run warm water into my sprayer tank, really helps in cool weather and a normally cold water source. I have resorted to using dawn soap with hot tap water to clean out the tank and lines. Not organic but seems to work better than the commercial tank cleaners.

Vista Ridge Orchard
Zone 8a in Washington
235 Cider and heritage apple trees, 72 varieties,

To Colin Lundy,
Im in Dundas the town, amalgamated into Hamilton 20 years ago but still DUNDAS <G>

Old 99 Farm and permaculture site
Dundas ON 5b

Photo of Rittenhouse tank, poor design
The tank has one fill opening on top 8" dia and one on the bottom, a fitting with outflow baffle on inside and screw nut on outside leading to shut off valve, inline screen filter and ball valve drain all below the tank and tough to access.
I think tanks should have removeable lid for thorough cleaning. Tank does not to be pressurized, right?
Or tank should be dismountable so it can be turned upside down and flushed. At very least there should be a flush drain on the bottom that is at the lowest point in the tank.
Inside of tank after season of HS spray mixes
Today I delivered Spring1 using soft water 25 usg, Neem 1pi, ie .5%, Nature Clean all purpose cleaning lotion 2oz (water, fatty polyglycocide, coco-betaine (surfactant), sodium citrate, carboxyl methyl cellulose (thickener) and aloa vera gel as stickifier (John Kempf idea). Mixed all ingredients in warm water first in pail, then added to cold water in tank with agitater on.
Had less trouble with neem foam residue but not none. Still had to rinse to get globs out. Used hot water and the 100 psi spraygun to dislodge. Since it clings to sidewalls, neem foam will not flow out the drain hole, is left behind.
Conclusion: make sure you buy a very cleanable tank, use soft ie rain water, premix neem and surfactant soap in warm water, say 100dF, experiment with amount of soap and brand to get best dispersal of neem.

note USG is .83 Imp Gal etc

I tried to get photos to load directly in the post, but could only make URL link work.

Old 99 Farm and permaculture site
Dundas ON 5b



Edited 2 time(s). Last edit at 04/14/2021 07:26AM by Ian Graham.

Colin and Ian - my father was born not far from you. His aunt grew glads and corn up there until recently (she passed away at about 100 y/o). Small world! now that this thread is completely off track - ha

Earthworks
Zone 7a in West-Central MD
Non-commercial, ~100 fruit trees, dwarf to MM106