Everything I have read about Neem Oil products states that they are broad spectrum poisons, they kill insects on contact and through ingestion. Some of these sources state that there is nothing to indicate these products harm beneficials, but that no studies have been done to see if there may be harm to beneficials. I have yet to find a pesticide that only kills insect pests and does not harm beneficial. How would this product know that this insect is not to be killed? Does the beneficial insect have some kind of ID tag to tell the Neem Oil not to kill it?
If you use Neem Oil products, or any other pesticide, read and follow the label directions carefully. However the objective of an organic gardener should be to not have to use any pesticide.

I have never seen it claimed anywhere that Neem kills anything on contact. It is effective against many types of insects, including LEAF MINERS!! Here is some accurate information put out by Cornell Cooporative Extension on Neem, how it works and what it is effective against -

Neem oil. Another group of neem products is made from the oil fraction of neem extract. The
active ingredient is generally listed as "clarified hydrophobic extract of neem oil," and is labeled
as a fungicide, insecticide, and/or miticide. Insects and mites susceptible to paraffinic
(petroleum-derived) horticultural oil are likely to be controlled to some extent by neem oil
products. The mode of action is probably similar to other oils, namely membrane or cuticle
Every effort has been made to provide correct, complete, and up-to-date pesticide recommendations. Nevertheless, changes
in pesticide regulations occur constantly, and human errors are still possible. These recommendations are not a substitute for
pesticide labeling. Please read the label before applying any pesticide. The information given herein is supplied with the
understanding that no discrimination is intended and no endorsement by Cornell Cooperative Extension is implied.
This document is a product of the Landscape Horticulture Program Work Team at Cornell University. Primary contributors include Paul
Weston, Department of Entomology and Dan Gilrein, Cornell Cooperative Extension, Suffolk County. Prepared June, 2007
disruption and/or interference with respiration. Note that the activity is distinct from that of
azadiractin-based insecticides.
Other neem products. In addition to products based on azadirachtin or neem oil, there are also
other pesticides derived from neem. One such product, K+ Neem, is an insecticidal soap made
from neem oil, listed on the label as potassium salts of fatty acids. Mode of action (membrane
disruption) and efficacy against arthropods is probably similar to that of other insecticidal soaps
since the product has no measurable quantities of azadirachtin.
What does neem control?
Although neem has a fairly broad spectrum of activity against insects, some insects are more
susceptible than others, and results often vary from pest to pest. Many leaf-feeding larvae are
susceptible to azadirachtin-based products; this list includes lepidopterous larvae (caterpillars), leaffeeding
beetle larvae, and sawflies. [NOTE: we have not seen significant efficacy against viburnum
leaf beetle larvae.] Fluid-feeding insects such as aphids, leafhoppers, and plant bugs are also fairly
well controlled by products based on azadirachtin, as are dipterous leaf miners and fungus gnats.
Adults of a number of insect groups are also responsive to azadirachtin; Japanese beetles and
grasshoppers reportedly avoid neem-treated foliage. Neem-oil products are reportedly effective
against aphids, whiteflies, scale crawlers, and spider mites. Neem products are generally not
effective against mealybugs, weevils, thrips, or adult scales. Use of neem products against pests not
on the label is not advisable because efficacy against these pests has not been determined (or is
inadequate), not to mention the fact that such uses are illegal in New York.

Here is more info from another reliable website -

How Neem Oil Works:
According to the EPA, "Azadirachtin and Clarified Hydrophobic Extract of Neem Oil are derived from the natural oil found in seeds of the neem tree.... When the natural neem oil is removed from the seeds and treated with alcohol, virtually all of the azadirachtin and related substances separate from the oil itself. The remaining oil - without the azadirachtin - is called Clarified Hydrophobic Extract of Neem Oil. Azadirachtin acts in the following ways: It deters certain insects, such as locusts, from feeding and it interferes with the normal life cycle of insects, including feeding, molting, mating, and egg laying."

Neem Oil As Organic Insecticide: Pests Killed or Repelled:
Neem oil kills some pests (after they've eaten leaves sprayed with neem oil), while it repels others with its strong smell. Neem oil is used to control many pests, including whitefly, aphids, Japanese beetles, moth larvae, scale and spider mites. Because it kills mites -- which aren't insects but, instead, related to spiders and ticks -- neem oil is listed as a "miticide." Sprays containing clarified hydrophobic extract of neem oil are also used as fungicides against rust, black spot, mildew, leaf spot, scab, anthracnose, blight and botrytis.

Benefits of Neem Oil for Pest Control:
Besides being an organic insecticide, using neem oil allows you to target pests, specifically, as opposed to beneficial insects (e.g., bees and lady bugs). By definition, "pests" are the insects eating your plants, and neem oil, properly applied, kills an insect only if it ingests the sprayed foliage (bees and lady bugs don't eat plant leaves).

Ron
The Garden Guy
http://www.TheGardenGuy.org
Informative articles, ongoing garden journal and
interactive message boards.

Everything I have read about Neem Oil products states that they are broad spectrum poisons, they kill insects on contact and through ingestion.

You posted a link in the other neem thread that indicated it doesn't kill on contact other than the same way any horticultural oil might on soft bodied insects like aphids.

You have seen posted here information on it's harmlessness to bees unless sprayed directly on them and even then it isn't anywhere near a 100% kill. Info has been posted in threads you have participated in indicating that even bees collecting pollen of sprayed flowers aren't killed. You have seen information here about honey bee keepers spraying their hives with neem.

You have seen here info from credible sources indicating lady bugs aren't harmed by it.

It has been explained to you numerous times by numerous people precisely what science has to say about neem.

Yet you continue to describe it as if it was Sevin.

Let's be very clear on this:

Neem may kill soft bodied insects that it is sprayed directly onto. Neem may kill insects that ingest plant material sprayed with it.

Other than that neem appears to be pretty benign to everything else. Humans ingest the stuff. It's used in health care products. Neem is one of the safest, least toxic pesticides that is actually effective against a variety of common plant pests.

Describing it as a 'broad spectrum, on contact' pesticide makes it sound like Sevin which it is not.

So, do you *now* understand what neem is and what it is/isn't toxic to?

There ARE targeted insecticides.....those that only direct their effectiveness at specific insects or insect types. Bacillus thuringiensis (Bt) is a common example, milky spore is another. While neem does have a much wider target base than either of these two examples, it IS a directed insecticide, targeting primarily sucking and chewing insects - aphids, spider mites, mealy bugs, scale, etc. Since the beneficial insects like ladybugs, ladybug larvae, mantises, parasitic wasps, bees and butterflies are not classified as sucking or chewing insects and tend to feed on other insects or on non-plant parts, like pollen, the neem poses a minimal threat to them. And there have been tests/studies done to confirm that this is the case......if one bothers to do the research, it's not all that difficult to find.

Depending on how the neem is applied, it can have a systemic effect - that is, it is transmitted into the plant tissues. Generally this is accomplished when used as a soil drench, as opposed to just spraying it on the foliage. The effect will be longer lasting when applied in this manner compared to the more common spray method. It is also found to have some deterrent qualities when used in this manner, discouraging some insects (the primary tests involved grasshoppers) from eating the treated plants at all.

The effectiveness of neem is not immediate. Because of its course of action - essentially hormonal disruption - it often takes some time to see clear evidence of its effectiveness. It takes time for those insect digestive systems to breakdown, or for them stop to laying eggs. It is not the immediate knockdown, kill everything, broad spectrum 'poison' some seem to think. But it IS effective and it IS pretty darn benign.

Those who persist in stating otherwise - i.e., that it is a non-effective, broad spectrum contact insecticide that will harm beneficials - do not have a good understanding of the product or how it works. Then again, I'm not sure they have much of an understanding of how ANY specific pesticide works :-)

It is indeed wearisome to hear the same things rigidly offered over and over again. "You can't do this or that and belong to the good organic gardener's club - your goals should be .... well, they should be MY goals - the cure to everything under the sun is to add more organic matter to the soil.

Incessantly pursuing dogmatic offerings in the face of an assortment of reasonable alternatives is not what posters here want to read. They don't come here to be preached to, but to gather useful suggestions and ideas so they can evaluate them for themselves. Telling them what they can and can't do, or what they should and shouldn't do is an affront to any individual's ability to make their own decisions or to reason through a problem on their own.

Neem's scope of effectiveness is concentrated heavily on those insects with rasping and sucking mouth parts - the ones that feed on plant saps. Tertiary mortality of non-target species is EXTREMELY low. If you have an absolute '0' tolerance for any impact whatsoever on beneficial populations of insects and bugs, then avoid all insecticides, because there are none that will ONLY kill targeted species. If you personally decide you NEED an insecticide today (not in three years after your soil has been made healthier via the inclusion of more organic matter, and your plants are bursting with vim and vitality), then neem oil is one of the very safest choices you can make.

Al

Al and Just A Guy,
You hit a homerun! The "fanatics" that are against everything and anything are what make organic gardeners look like kooks to some.

There are great completely organic products available that make organic gardening not only work, but practical and productive. To put these products into the category of toxic chemicals is not only uninformed abut irresponsible.

My goal in over 50 years or organic gardening and farming has always been to keep as much toxic chemicals as possible out of my food and enviroments, while at the same time enjoying my garden, nature and the art of gardening itself. If I have to occasionally kill a beneficial to save a crop, I have no problem with that, because my healthy soil and crops soon attract many more to take their place.

Ron
The Garden Guy
httpa://www.thegardenguy.org
Informative articles, ongoing garden journal and
interactive message boards - All FREE!

Exactly - try as hard as you can, you/we still may find ourselves in a situation where we feel we need to use a product we might not normally use, and I'm not necessarily referring to neem oil, because it IS so innocuous. Reasonable people understand this and adjust. We can't tout the principles of IPM in one breath and eliminate the possible use of every insecticide known to man in the next and expect retain credibility.

I wish Dori (Rhizo) was around to weigh in on this. She is probably more acutely aware of many problems caused by chemicals and insecticides than many or most of us & I respect her opinion.

I've been a member of GW for a good number of years, and I used to visit this forum regularly, but I found myself constantly entrenched against the same one or two vocal individuals with extremely narrow perspectives about what was or wasn't a good garden practice. I just grew weary of it, choosing to only pass through occasionally (though I've spent a little more time here lately) and to look elsewhere for my fun.

Sorry, Lolear. I know it's your dime. ;o)

Al

All I am inclined to do right now is pinch somebody's teeny little head off. ;-) So, I think I'll 'weigh in' at another time. Besides, you all have done a great job at educating!

But let me answer our poster's question:

lolear, I don't believe that any pesticidal product should be applied regularly and on a schedule as a prophylactic measure. You certainly don't want to use insecticidal soap for that purpose. You really could harm populations of beneficials with routine, non-targeted applications of that product.

Be a good detective to observe populations of pests while they are small enough to target directly. And (my best advice...so listen up, lol) take some time to get to know your insects, good and bad. Learn what they look like, as well as how they can be expected to behave. Your job at pest control would get a lot easier, believe me. A good field guide would be a good place to start.

The instructions on the bottle of neem were a bit vague, precipitating my original post. Also, it has been raining a LOT. further confusing when it's okay to spray. I guess my suggestion of using neem as a preventative must come from reading somewhere that since neem works by disrupting the various life cycles and does not have a knockdown kind of action, it takes a while to work. If that is the case, then you are effecting specific insects you have sprayed, while others you might have missed could come in and take their place.
I have been doing a lot of reading since I am a newbie, but that usually leads to more questions... When I found that insect I rushed in to consult the bad insect illustrations and IDed it before picking it off (with surgical gloves and tissue) and flushing it down the toilet. When I removed the backyard lawn to make way for the veggie beds, I inspected each handful of sod for worms and kindly replaced them in the soil. I am the kind of nut who prefers not to hurt anyone, but this has been a pretty significant effort and I would like to see the fruits of it. Thank you for getting to the crux of my (innocent) question.

Most products meant to be applied to plants directly to control pest/disease need to be reapplied after significant rainfall as they aren't waterproof.

Ideally the label will indicate such things and other pertinant info. May I ask which product you are using? With just regular neem oil it's common to apply weekly as long as a problem persists as well as after any significant rain, but it's best to know what product we are talking about so we don't lead you astray.

Even fairly safe products like neem are best used with respect.

The product is Green Light Neem concentrate, which I have diluted to the recommended proportion.

What is considered "significant" rainfall? It's been raining every other day for a week or so...

I would define significant rainfall as 1" of rain whether all at once or cumulatively. That much water running over the leaves will likely remove the oil.

So, the pests your plants are being bothered by are mites and aphids? Are they under control yet?

At the moment, things seem under control. I had a mite infestation in a flower container. Although the mites seem to be gone, the plants look none too good. I think I am going to start over with that one. One of my columbines had aphids pretty bad and they seem to be gone after several soap applications. Interestingly though, the flowers of the columbine I sprayed are a much lighter shade than the other 2 plants of the same species and variety right next to it that were unaffected by aphids and were not sprayed. Could the soap or the aphids have caused the color change? I am trying to keep a sharp eye out on everything and nip problems before they explode. At the moment the biggest problem is the colder than normal temps. Everything seems stunted and a little fragile...

I suppose the lighter color could be a byproduct of the pest damage weakening the plant. The too cool of weather isn't healing the plant recover either. I understand where you are coming from on the weather as I am dealing with it too.

Normally May 20th it's safe to put warm season plants outside, but there is a possibility of patches of frost tonite and it's June. Plants seem to be in stasis.

Oh well, once the summer finally arrives I will complain about it being too hot ;)

I intend to use neem only on my grub infested soil as a long term remedy and app. method.

But now I turn to another pest that I have mainly on my coral honeysuckle I have tried all methods water blasting and ladybugs with very little help. Lady bugs may be ok with simple or open air smaller plants but not the likes of a big thick vine as mentioned above.

First of all after fighting the aphids these last 3 yrs to no avail I deciced to cut it down to nothing last fall . Only three main stems remained with not a single leaf left.

So this year I started using - liquid seaweed- after reading a great deal and getting info from other people. From what I understand this has a lot of micronutrients when used weekly as I am will strengthen and make more healthy and stress free plant. Apparently this stress free plant produces a sucrose when eaten by an insect or mite turns to alcohol and kills the vermin. Im not sure at this point how effective this will be but I have a goldflame and coral honeysuckle which are now well budded with no sign of ahpids as yet. The real test will be late may/june. But right now looking good.

is neem oil effective for spider mites?

Yes, be sure to apply it to the underside of the foliage, where it can do the most good. Read and follow the directions on the label of your product.

All neem products are not created equal. The highest concentrations of azadirachtin (the active ingredient) will be found in pure, cold-pressed products, such as that packaged by Dyna-Gro.

How I use it:

In a 1 quart hand spritzer, start with a pint of very hot water mixed with a few drops of Murphy's Oil Soap or other natural soap. You can use insecticidal soap for this part if you wish. Add 1 teaspoon of neem oil. Shake well & add a pint of rubbing alcohol. Shake well again. Spritz the plant, covering ALL surfaces. As Dori mentions, make sure you cover the under side of leaves & that you get the solution into leaf axils (crotches).

Neem's value lies in the fact that it disrupts several aspects of a pests life. It sterilizes insects so they can't reproduce; it has anti-oviposition (anti egg laying) properties; it disrupts molting so insects cannot progress through their life cycles; it is also a powerful anti-feedant, making your plants taste bad and upsetting digestion; it inhibits flight ability, which also helps stop the spread of pests.

Al

FWIW, I make my own Neem and/or Karanja oil soap that has about 40 percent of those oils in the final product.

After curing I dissolve a 4 ounce bar in a gallon of hot water and use the resulting mixture at about two ounces per gallon as a pesticide spray.

Helps with sucking pests.

These oils are a mild pesticide that work fairly well IMHO.

So for those of you who make your own soap, you might want to make a strong Neem or Karanja oil homemade soap for this purpose.

I've been appreciating your excellent information and advice as I regularly research the best practices for my organic garden. I'm currently looking into neem to control aphids, spider mites and saw fly larva on my climbing roses, ornamental plum trees,and fruiting plum trees.

For the past four seasons I've just used water spray for knock down which has had limited success. I just live with the damage as a trade off to not using any pesticides while I build up my garden to attract benificials, and add oceans of organic matter to build up my soil health.

This year I've decided to try neem to minimize the stress from these pest attacks to the plants which are doing well enough but could be better. After the initial attack and water spraying it's a constant battle for the rest of the season as the plants obviously weaken and become more susceptible to other pests and diseases such as on and off aphids, warm season spider mites, rose slugs and midges, powdery mildew, and black spot. I think a neem treatment or two now may increase their disease resitance for the rest of the season by minimizing the damage being done
right now in early spring.

Tapla (Al) has posted he uses a dilute mixture of cold pressed neem, a few drops of soap, and rubbing alcohol. Please comment on the addition of rubbing alcohol, it's purpose as well as it's possible photo-sensitivity damage or burning to leaves/buds/flowers/fruit. I know to spray late afternoon to avoid bees, and will follow neem label directions to avoid any other possible plant damage.
Thanks, Cheryl