Neem oil damaging trees

[Tbwilson33]

Hey everyone, so my issue has been some insects lately scale, aphlids, and spider mites. I’ve used neem oil and every time I’ve used it yes the infestation is gone but my trees are damaged. I’ve tried different methods of application. Like spraying the trees down with fresh water in the morning. And keeping the trees out of the lights for a day. And this last time I did all of said things and went with a lighter spray. And the leaves of fresh growth are yellowing and falling off my tiger bark ficus. I’m feeling pretty discouraged so I bought some insecticide soap. But I’m nervous that this going to happen again. So I guess I wanna know am I doing something wrong?

 

[JoeH]

I've seen a little damage in the heat of the summer, nothing major tho. I've never seen neem do any long term damage to landscape trees. The soap should be a lot more trustworthy. There may be other factors that you are missing too. Hard to say without knowing location, tree types etc.

 

[Tbwilson33]

I've seen a little damage in the heat of the summer, nothing major tho. I've never seen neem do any long term damage to landscape trees. The soap should be a lot more trustworthy. There may be other factors that you are missing too. Hard to say without knowing location, tree types etc.

These are my tropicals so they are inside. Live in zone 5 Connecticut. Some of the trees that got damaged were tiger bark ficus, Brazilian rain, Texas ebony. European olive, Barbados cherry.

 

[JoeH]

did you have some trees that weren't damaged?

 

[Tbwilson33]

Yeah my green island ficus was fine, umbrella tree, and my burrt ficus

 

[Potawatomi13]

Had bug killer something once maybe this in it was great irish(false)moss killer. Could not get after that(curses). Had same result as you on new foliage of Vine Maple! Currently use insecticidal soap with protection from direct Sun.

 

[Wilson]

I have never had issues with neem, but just recently a friend told me his fukien tea was burned after using it. I am curious how people are mixing their ratios? I buy pure neem oil from the indian grocery stores, so I don't know what the "horticultural neem" is like.

 

[Tbwilson33]

Is there any advice you guys can give me an insecticidal soap? I’m really trying to avoid anything like this again

 

[Potawatomi13]

Is there any advice you guys can give me an insecticidal soap? I’m really trying to avoid anything like this again

Protect tree from direct sun a couple days. Avoid new unhardened foliage if possible. Personal pines not as sensitive as deciduous.

 

[Forsoothe!]

Rate of application is pivotal, but not the only issue. Thin leaves like Brazilian Raintree and Huascache can't take any oil spray at all, but if you have a problem with figs, you are doing to the leaf what you're supposed to do to the bugs: suffocate them by closing off their breathing pores. They're on the sides of bugs and the underside of leaves. Hort oils are vegetable oil, not mineral oils, and must be very light weight. My instruction sheets ( Gardensalive.com ) for Pyola say 1 to 2 tsp per quart (a pyrethrin & Canola) and Shield-All, 2 tablespoons per gallon (a pyrethrin & Neem). I use the lower amount for sprays and double the rate for drenches. I make it with hot water the first half shaken violently, followed by cold water. I think it disperses better that way, but I have to keep shaking the bottle in-between plants because it settles to the top of the bottle PDQ. I always drench the soil because anyone hiding down there in any stage of development has to pass through the surface soil to get out, and egg layers get it going in.

It's hard to measure those small amounts so if you err, be it on the low side. I believe in overkill or nothing, so I also use Bayer Once-a-year Rose Systemic 3 times a year for my tropicals: autumn when I bring them into the greenhouse, spring when they start to grow, and about June. The white flies and black flies follow me in anyway, and I treat every 6 to 8 weeks with a Knock-Out-Gnats drench.

There are no easy answers. Except, of course to use a dish soap spray after which you pick them off by hand. Your bugs will smell nice and be very clean, and your finger tips used-up, to say nothing of your patience.

 

[Tbwilson33]

So you would recommend drenching the soil? Is that safe with the soap? Or just with pyrethrin and neem?

 

[Forsoothe!]

I don't think you can hurt anything with soap, except maybe if it's too thick?/strong, not dilute enough, and maybe not even then. I prefer poison, I'm that just kind of guy. Bugs gotta make a living, but so do burglars, car thieves, muggers, etc., and I defend my territory as best I can. I don't kill indiscriminately. There are lots of good bugs that are on my side eating other bugs, so I don't apply everywhere. Roses need lots of protection, I have lots of Hosta, so slugs are on my hit-list, my greenhouse is off limits in winter, but open in summer. All else is bug city so I suppose it's in balance? No harm, no foul. The systemic I use on my potted trees may ward off evil spirits that I don't know about, but I like my results.

 

[amcoffeegirl]

I have used neem on a few willow leaf this fall with no ill effects. I used it very liberally. Spraying on top of the leaf, underneath and on the soil. I sprayed once every 10 days for 2 months.

 

[Forsoothe!]

I have used neem on a few willow leaf this fall with no ill effects. I used it very liberally. Spraying on top of the leaf, underneath and on the soil. I sprayed once every 10 days for 2 months.

For what pest?

 

[Potsofgreen]

I cut my neem oil with dr.bronners tea tree soap in spray bottle first to thin out the oil then add the water shaking vigorously if you use the oil straight it’s no good

 

[Forsoothe!]

I cut my neem oil with dr.bronners tea tree soap in spray bottle first to thin out the oil then add the water shaking vigorously if you use the oil straight it’s no good

What's your rate of dilution? How much neem to a quart?

 

[Potsofgreen]

Maybe 2 tablespoons oil to 1 teaspoon of soap I don’t measure anything I just know by the look of the solution after I add water, and I use filtered water to fil up spray bottle not tap

 

[amcoffeegirl]

For what pest?

Soft scale.

 

[JoeH]

So you would recommend drenching the soil? Is that safe with the soap? Or just with pyrethrin and neem?

neem may work as a drench, soap won't tho. It will be slower to take effect on the critters, as it has to work its way thru the plant.

 

[Forsoothe!]

Soft scale.

If you have to use neem every ten days, then something's rotten in Denmark. One application should do it; maybe, one more as a follow-up to get the eggs you missed in the axils, but that's it. I suspect, but don't know, that your soap is an emulsifier that is encapsulating the neem such that you are coating the scale with soap, thus protecting the scale from the neem. Capisce? Try it without the soap and see what happens...