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About Neem Oil

For any that might be interested, I wrote this as an article for our bonsai club newsletter, but it applies to houseplants as well.

Neem extract as an insecticidesize>

In India mainly, but also Asia and Africa, grows a tree all bonsai enthusiasts should be aware of: Azadirachta indica. You are probably already wondering if it makes a good subject for bonsai. Well, yes and no. I don't know enough about the tree's culture to say it makes a good bonsai medium, but it makes a very good bonsai subject. I'll explain: Azadirachta indica is commonly known as the "neem" tree. Extracts from the tree contain azadirachtin, a relatively safe and effective naturally occurring insecticide. Let me preface the following comments by reminding you that the terms "naturally occurring and/ or organic" do not universally mean safe. Pyrethrums, rotenone, and even the very dangerous nicotine are all organics that should be handled with great caution.

Neem extracts, on the other hand are used in a wide variety of cosmetics, as a topical treatment for minor wounds, to treat stomach ailments, as an insecticide in grain storage containers, bins, and bags, and a whole host of other applications. I'll limit this discussion to its use as an insecticide.

Neem works in many ways. It is effective both as a topical and a systemic. It is an antifeedant, an oviposition deterrent (anti-egg laying), a growth inhibitor, a mating disrupter, and a chemosterilizer. Azadirachtin closely mimics the hormone ecdysone which is necessary for reproduction in insects. When present, it takes the place of the real hormone and thus disrupts not only the feeding process, but the metamorphic transition as well. It interferes with the formation of chitin (insect "skin") and stops pupation in larvae, thus short-circuiting the insect life cycle. Tests have shown that azadirachtin is effective in some cases at concentrations as low as 1 ppm.

Neem oil or extract is most often used in an aqueous (water) suspension as a foliar spray or soil drench. Commonly, it is diluted to about a .05% solution, but the suggested ratio for use in bonsai culture is 1 tsp. per quart of warm water. A drop or two of dish soap (not detergent) helps keep the oil emulsified. The mixture is then applied as a mist to all leaf and bark surfaces and as a soil drench to the tree's root system. It should not be applied as a foliar spray on hot days or in bright sun as leaf burn may occur. Remember to agitate the container frequently as you apply and do not mix anymore than you will use in one day. Neem breaks down rapidly in water and/ or sunlight. (Since writing this, I have discovered that a 50/50 mix of water/rubbing alcohol works very well as the vehicle)

Some users of insecticide need to be able to observe the instant results of their efforts in order to be convinced of the effectiveness of their choice.The application of neem derivatives does not provide this immediate gratification. There is virtually no knockdown (instant death) factor associated with its use. Insects ingesting neem usually take about 3 - 14 days to die. Its greatest benefit; however, is in preventing the occurrence of future generations. It is also interesting to note that in studies it was found that when doses were given, purposefully insufficient to cause death or complete disruption of the metamorphic cycle, up to 30 surviving generations showed virtually no resistance/immunity to normal lethal doses.

I have been using neem oil for about 7 years as both a preventative and fixative and have had no insect problems on my bonsai. It is said to be effective for mites, whitefly, aphids, thrips, fungus gnats, caterpillars, beetles, mealy bugs, leaf miners, g-moth, and others. It seems to be fairly specific in attacking insects with piercing or rasping mouth parts. Since these are the pests that feed on plant tissues, they are our main target species. Unless beneficials like spiders, lady beetles, certain wasps, etc. come in direct contact with spray, it does little to diminish their numbers.

Neem oil does have an odor that might be described as similar to that of an old onion, so you may wish to test it first, if you intend to use it indoors. I've found the odor dissipates in a day or two. As always, read and follow label instructions carefully.

Neem oil can be purchased from many of your favorite bonsai suppliers or via the net.

AL FASSEZKE

Comments (41)

  • notanatural
    17 years ago
    last modified: 7 years ago

    Tapla, thanks. That was very informative. I'm a big believer of Neem (Sanja can probably attest to this as well). And yes, I would say that for most of the times I have used it (mostly as a kid though), it was always more of a preventative/slow cure rather than an immediate one. I remember using neem sticks when we pierced our ears- to prevent infection. I very very strongly attest to that!!

    Funny thing is, it's a tree I've grown up hearing about, using, but if you ask me what it looks like- NO CLUE!!! That's how oblivious to the plant kingdom I was- up until now that is.

    Gonna go get some neem oil from the Indian stores near me. I bet they're much cheaper than the garden center I was at y'day- and probably much cheaper than online as well.

    Ok, one more question Tapla- is it only Neem oil that seems to have these benefits for plants? What about other beneficial oils such as 'tea tree oil' for example?

  • username_5
    17 years ago
    last modified: 7 years ago

    Good info, Al.

    I recently 'discovered' neem and have begun trying it out in various ways.

    Seems very promising.

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  • notanatural
    17 years ago
    last modified: 7 years ago

    Ok, was trying to find more info and read something that said Tea Tree Oil and Neem are the same thing? Wow! Never knew that. Is that true? There's so much info (some worse than the others) out there, I never know what to or not to believe.

  • username_5
    17 years ago
    last modified: 7 years ago

    Tea tree oil and neem oil are not the same thing.

    Melaleuca Alternifolia is a species tea tree oil is from and Azadirachta indica is the source of neem oil.

    Then again, what is in a common name? Could be that some sources conflate the two.

  • tapla (mid-Michigan, USDA z5b-6a)
    Original Author
    17 years ago
    last modified: 7 years ago

    There are many trees (dozens) with the common name Tea Tree (kind of like "cedar"), most of which are in the genera Melaleuca and Leptospermum. As noted in the info above, the neem tree is in the Azadirachta genus. I'm sure username's identification of the source of tea oil is accurate, so I'll not bother looking into it.

    Al

  • sanjna
    17 years ago
    last modified: 7 years ago

    Funny - For some reason I remember being made to drink "neem juice" as a kid to clear up my skin - it was the most foul tasting substance I ever drank and if I were an insect I'd curl up and die too. My toes are curling just remembering the taste! Al, I feel sorry for your insects!

  • notanatural
    17 years ago
    last modified: 7 years ago

    LOL! I'm glad I don't remember drinking any! I remember being made to put neem sticks in my newly pierced earholes as a kid- to prevent infection.

    Well, just got some today- so watch out mites, here I come!

  • rjm710
    17 years ago
    last modified: 7 years ago

    Al, thanks for the well written post! My question is, does Neem Oil have any advantages/disadvantages when compared to other less toxic insecticides, such as insecticidal soap or horticultural oils? Is one better than the others for any particular situations?

  • username_5
    17 years ago
    last modified: 7 years ago

    rjm,

    I asked a very similar question in another forum a while back.

    Long story short is that neem oil does work like a summer oil and insecticidal soap, but it doesn't appear to be as effective as either one for those purposes. There are, of course, different forumulations of the stuff so the 'inactive' ingredients can affect this.

    The primary function of neem is preventing bad bugs from colonizing a plant. You know, a few bad bugs arrive and happily start munching/sucking on your plants. Then they have babies, lots of em, and before you know it an entire extended family of bad bugs are decimating your plants.

    Neem acts as an anti feedant, discouraging the bugs from finding your plant tasty. If they feed anyway it disrupts the function of their mouthparts so they can't feed effectively. It prevents adults from laying eggs and prevents larva from pupating.

    As such most sources I have read suggest it is most effective when used as a preventative to prevent the population of bad bugs from getting out of control. Once the infestation occurs, many report the effectiveness of neem to be not so great.

    Of course, I have simply reguritated what I have read/heard from others. I purchased a Safer Brand neem product and intend to try it out next year on potted plants, fruit trees and in ground veggies. As such I am not speaking from experience.

  • nanw_4wi
    17 years ago
    last modified: 7 years ago

    I, too, appreciate this information, Al.

    I don't have a lot of experience with Neem Oil myself, (only recently purchased some and used it on just a few plants) but just wanted to call everyone's attention to this post on the Sansevieria forum regarding those plants and Neem Oil.

    Seems there is always at least *one* type of plant that is sensitive to any given insect remedy.

    Here is a link that might be useful: Neem Oil and Sansevierias

  • tapla (mid-Michigan, USDA z5b-6a)
    Original Author
    17 years ago
    last modified: 7 years ago

    rjm - I don't know what's out there that would be less toxic than neem. Even the water/alcohol mix many of us use as a fixer for pests is likely far more hazardous than a neem/soap/water mix. It's certainly as safe as insecticidal soap and as others have noted, it's taken internally in many parts of the world.

    It's difficult to compare it to the oils unless you pick one. I think I outlined the disadvantages in my "article". It stinks, it's some work to keep it emulsified, and it can burn if applied in full sun. Other than that ...

    Nan - As I read through the post you linked to, it wasn't clear what product the person used & I got the impression there was an "inexperience factor" involved after reading that he/she mixed the product 50/50 with water. Since neem won't mix with water w/o an emulsifier, I suspect it was another product with an organic solvent as the vehicle and likely it was the vehicle that did damage because of the strong solution, but who can tell?

    When I started using neem oil quite a few years ago, all that was available was the cold-pressed raw product. It works so well I've not tried any of the newer formulations that have hit the market in recent years to cash in on its known effectiveness. I can't vouch for anything other than the plain ol' oil.

    I use it mainly as a remedy to existing infestations. Because of the soils I use, I'm watering every day & I prune stuff that nobody else probably thinks of pruning. :o) (Can't help it), so not much in the way of insect problems gets by me. I'm always flipping over leaves & tapping plants to see what I can flush out of hiding. Anyway, when I find more bugs than I'm comfortable with, I usually neem 'em. Since there's no instant death (knockdown) associated with its use, it usually takes about a week or so for the plant to be rid of unwanteds. It works systemically as well as a topical, but I'll often follow up with a second application after about 2 weeks.

    As a preventative, I use it on all my tropical and subtropical trees and houseplants before I bring them in to winter over. I'll do an application about 2 weeks before I expect to bring them in and again a couple of days before cold weather forces me to move plants indoors, kicking and screaming.

    Last winter, I had no pest problems indoors until about May, when a few whiteflies showed up & I noticed a few mealies on a Ficus. Since it was so close to time to move the plants out for summer, I used another systemic on the affected plants & it cleared things up. I try not to use it indoors. The only reason is I have around 100 trees & it would be too stinky to apply enough neem to treat all the trees and plants. Plus, I'd have to carry each plant upstairs to the shower to apply and then clean the shower.

    I don't have a problem with responsible use of chemical insecticides and in recent years, I have had superb results with a particular systemic. If I was limited to the use of only one insecticide, the choice would be difficult, but I would be perfectly happy being limited to the use of just neem oil. If I was looking for something known to be extremely safe or something organic, the choice would be clear - neem oil, hands down.

    Al

  • GrowHappy
    17 years ago
    last modified: 7 years ago

    I'm a huge advocate of Neem Oil. I can vouch only for the product made by Dyna-Gro, which is 100% pure neem oil. I've used it on many of my tropicals(Sans included) w/o ill effects and with the desired effect.(grammatically correct???) I'm always careful to use it exactly according to the package directions. During the summer when many of plants were on vacation out there, I used it either in the very early morning hours or late evening, and NEVER left a plant treated with Neem in direct sun.

    I use Neem mostly as a preventative. It also doubles as an organic leaf shine, which I love.:)

    GH

  • tapla (mid-Michigan, USDA z5b-6a)
    Original Author
    17 years ago
    last modified: 7 years ago

    I use the same, GH.

    Al

  • jcpyburn
    17 years ago
    last modified: 7 years ago

    Hi,

    I have a question about this. I want to use something to treat all my houseplants that are inside as I have fungus gnats. I have tried the alcohol/water solution and it helped for a while but they have rebounded. I want to do something that will kill every bug in all the pots and do it all at the same time so that they don't go from one plant to the other. I don't really have a big problem right now but I would like to use it to clear out anything that rode in with some of the plants. I should have done it before I brought them in but I had to bring them in in a hurry. I don't really like chemicals but will use them if they are safe to use inside. Al, I know that you have recommended a systemic(Right word??) on other threads that I can't think of the name of right now, but can you compare what the pros and cons are of that compared to neem oil in this situation? All the plants will be treated inside and none would be in direct sun. Thanks!

    Carly

  • tapla (mid-Michigan, USDA z5b-6a)
    Original Author
    17 years ago
    last modified: 7 years ago

    I replied off forum, Carly.

    Al

  • creatrix
    17 years ago
    last modified: 7 years ago

    If you can't leave a plant treated with Neem in direct sun, how could you use it on vegetables?

  • username_5
    17 years ago
    last modified: 7 years ago

    You can use it on a plant in direct sun, it should simply be avoided when temps are real high as a precaution. The same is true for anything that qualifies as a horticultural oil.

  • tapla (mid-Michigan, USDA z5b-6a)
    Original Author
    17 years ago
    last modified: 7 years ago

    It's best applied on cloudy days or in the evenings.

    Al

  • jon_d
    17 years ago
    last modified: 7 years ago

    Having just read this thread for the first time, I want to thank you Al for your information. I will have to try Neem now, so I can compare it to the stuff I currently use. It would be nice to have a two prong approach to mealies, thrips, and mites. I see you have used it with a mix of 50/50 alcohol/water or with dish soap (Ivory?). Which one do you now prefer? I guess my relunctance over the years in trying Neem was reading various comments that it "didn't work". Your explanation that it isn't a quick kill type product seems to explain this type of observation.

    Jon

  • tapla (mid-Michigan, USDA z5b-6a)
    Original Author
    17 years ago
    last modified: 7 years ago

    You're most welcome, Jon. I now use it almost exclusively with a 50/50 mix of alcohol/water + some Ivory. I don't know if Ivory is any easier on leaves or not. I bought a bottle 100 years ago specifically for plants because I read it was "the only thing to use". It's done no harm, so I'll likely stick to it. I suppose they use the same surfactants as the other detergents, but who knows? The bottle I have says it "doesn't remove the natural oils in my skin", & lovely hands are soo important to me. ;o) It doesn't list the actual surfactant(s). (Sodium laurel sulfate or sodium laureth sulfate?) Just guessing.

    I know it (neem oil) to be very effective on most rasping/sucking pests - just not fast. Again, my experience is limited to the cold-pressed product. When I was doing some research on neem before writing the short article several years ago, some of the info I found mentioned that steam or hot water extraction reduced its effectiveness as an insecticide.

    Cheers.

    Al

  • SambaDeb
    17 years ago
    last modified: 7 years ago

    Al, I was eagerly following this thread, esp after Carly's question about treating all her plants. And then you replied off forum. Probalby a savings in time and space, but exactly the answer I wanted to hear. Is there a way to bring that discussion back on-forum?

    I'm a newbie on this site, so if i'm stepping on protocal, I apologize.
    Deb

  • tapla (mid-Michigan, USDA z5b-6a)
    Original Author
    17 years ago
    last modified: 7 years ago

    She was inquiring about some systemic insecticides & I didn't want to name them on the forum. There are readers that are able to responsibly use almost any chemicals available, but there are some that are not. I didn't want it to seem like I advocate the wholesale use of insecticides. I use neem as often as I can, and would use it almost exclusively if the number of plants I would need to treat indoors would allow.

    I always prefer to use the safest remedy first in an attempt to keep insect populations to an acceptable level. I guess that comes pretty close to summing up IPM (integrated pest management). I'll respond off forum if you want more info.

    Al

  • supercet
    16 years ago
    last modified: 7 years ago

    I live in LA on the third floor with a west facing balcony. After two years of bug free living I seem to have a moderate infestation of all sorts. The mealy bug on the house plants is now outside all over my succulents. We have eggplants, tomotoes and peppers which don't seem too happy, I find random little bugs on them (I don't think they're aphids), I discovered white chalky powder (definitely different to mealy bug) on one of my succulents and I have spider webs over my bougainvillea. From about 1pm till sunset the entire balcony is in full sun. Can I use neem oil in the evening on these plants, or should I wait till September when it will be cooler? (Assuming my plants can survive that long). I've tried the rubbing alcohol for the mealy bug but all it's doing is keeping them at a steady level ie, they die down and then after two weeks it's time to respray (in fact, I have so many miscellaneous problems that I'm going to post on each forum for each plant/pest!)

    Between the cat, veggies and full sun I'm reluctant to use too much pesticide. But I'm at my wits end - my once lovely balcony is starting to look wilted and tired! I heard about worm castings and wonder if that would help anything? Is neem oil the answer to my problems? Is it safe on succulents too?

  • conifer_1939
    15 years ago
    last modified: 7 years ago

    I've heard that Neem Oil can damage micr-organisms in the soil, therefore damaging the enviroment. Does anyone have any evidence of this?

  • tapla (mid-Michigan, USDA z5b-6a)
    Original Author
    15 years ago
    last modified: 7 years ago

    Do you? What do you consider damage? Walking in your garden kills millions of micro-organisms with every step. Is that damage? Let's think logically for a moment.

    Any "damage" done by neem applications (if there was any), because of it's physical properties would be highly localized. We're not talking about broadcasting neem oil from airplanes like napalm or agent orange here for crying out loud. ;o) We're talking about using it on a few containerized plants.

    Neem oil is a natural compound and breaks down very quickly in sunlight & soils. It is similar to coconut oil in its physical properties, and it's not water soluble, so it remains very localized in soils in addition to its rapid deterioration. The active ingredient, azadirachtin, is not a neurotoxin like most insecticides. It doesn't kill insects outright. It's value as an insecticide lies in the fact that it is an anti-feedant and that it (azadirachtin) closely mimics the hormone ecdysoneis and short-circuits the metamorphic cycle of some insects.

    Does it kill some soil fauna? Probably not in significant numbers. If it did, would it be of any major significance? No, and it's not phytotoxic either. Microbial populations are a constant boom/bust in containers anyway, so if neem is toxic to some soil organisms after having been used to stave off a problem infestation - so what? We don't depend on microbial activity in container culture anyway.

    Neem is used in lipstick, orally taken remedies for gastric distress, grains to stave off insects (so it's regularly ingested), etc. It's also WIDELY and effectively used to overspray crops in many countries (like crop dusting), including the US.

    I would poopoo the supposition that neem applications are of any concern to the environment until you or others can show something other than "Chicken Little" anecdotes that gives cause for concern.

    Al

  • carawaykara
    15 years ago
    last modified: 7 years ago

    I just got some neem oil from Mountain Rose Herbs (they carry excellent herbal products). I am using a mix of colloidal silver water, aspirin and neem oil as a preventative/tonic spray on all my vegetables.

    I always appreciate your posts Al, I am new to this forum and have learned a great deal. I ahve also been using your potting mix for all my container plants and they are all looking great.

    John

  • tapla (mid-Michigan, USDA z5b-6a)
    Original Author
    15 years ago
    last modified: 7 years ago

    Thank you for the kind words, John.

    What you have may not be effective as an insecticide or feeding deterrent. When the natural neem oil is removed from seeds, alcohol is used and 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 and is probably what you will get in herbal preparations.

    Cold-pressed neem oil contains the effective ingredient (azadirachtin) and is what you should use for best effect.

    Al

    Here is a link that might be useful: Click me & see first item on page .....

  • mchander123_yahoo_com
    14 years ago
    last modified: 7 years ago

    I have lost several tropical plants to spider mite infestations despite using Orthenex. I am ready to try neem oil, and would like to know where to find the Dyna Gro product?

  • tapla (mid-Michigan, USDA z5b-6a)
    Original Author
    14 years ago
    last modified: 7 years ago

    Click the link I left immediately above your post, or search "Dyna-Gro" neem oil and you'll find multiple sources.

    Al

  • vegetablesoul_yahoo_com
    14 years ago
    last modified: 7 years ago

    neem cake (the left over nut pulp from cold pressed neem oil is used as a fertlizer in africa and india (or so i've read) it seems to aside from adding nutrients adds immunity to plants. i tested a while back two green peppers, using neem oil in the water for one, and none in the other. grown hydroponically, the neem oil pepper didn't get the spider mites that attacked the greenroom, and was incredibly larger than the other control, so hmmm... in our bodies as medicine, neem helps our immune system as well as acting as an anti fungal parasite, so perhaps it works much in the same way in plants... a wonderfully useful plant!

  • cacye
    14 years ago
    last modified: 7 years ago

    I had better luck with neem oil to get rid of head lice(they were gone in a little over a week)than I had with using it on scale insect on Schefflera(I had to get rid of the plant as it was spreading scale to other plants. It was just too big to effectively coat). I have also used neem oil on strep- it is very useful and will take care of folliculitis better than the antibiotics.

  • meyermike_1micha
    13 years ago
    last modified: 7 years ago

    I have a good question.....I myself have about 30- 40 plants in one room. If you use neem oil and any other good natural product, and hit up every plant, to the point where none are seen and on a regular basis,how long before the insects are truly left dead, especially all the ones still hiding in our window sills, crevices of wood floor,walls,fabrics, or anywhere else other than the plant themselves in that same room?
    I have heard that all it takes is one trip to a greenhouse infested with mites, and they can travel on your clothes just to hop on a plant in our homes.
    I know spraying and hitting every plant is a great idea, but what about all those just lerking in the places we could never hit with kneem oil or any other great product? Would we have to soak every part of the plant room ?
    Are we to conclude we can never ever get completely rid of the pests indoors, just keep them under control?
    If no is a realistic answer, then I can feel like I have not failed at using neem since evry two weeks these pests seem to come back anyways. Maybe from all surfaces except my plants. I can just picture them jumping of all my plants while I spray, just to jump back on from all these hidden places to feed again.
    Thanks

  • tapla (mid-Michigan, USDA z5b-6a)
    Original Author
    13 years ago
    last modified: 7 years ago

    There are many products on the market that claim 'neem' as an ingredient. Often, the 'neem' is combined with other insecticides and a vehicle that makes emulsification and thus delivery/application easier. If these products have used neem oil that was altered or obtained by a process other than cold-pressing, the value or effectiveness of the essential ingredient azadirachtin has likely been reduced or negated entirely.

    I have read reports in these & other forums about growers using products like Bio-Neem by Bonide (and others) and having less than what they consider stellar results, while I continue to use the cold-pressed product, such as is produced by Dyna-Gro, with what I consider very safe and very good results.

    Remember that neem oil doesn't deliver a huge initial knockdown punch, but it IS a powerful antifeedant and chemosterilizer, rendering current generations unable to feed or progress through metamorphic stages to adulthood, and rendering adults sterile.

    Cold-pressed neem oil is excellent on mites & works initially in the same way as hort oils work, with the added benefits of the other properties already noted.

    This from a recent post @ another forum site:

    "As I consider the prophylactic use of any insecticide, including systemics, I guess I have to say that about the only compound that fits that description for me is neem oil. I over-winter around 100 tropical plants (most are normally grown as houseplants, but my focus is on bonsai) under lights in my basement. About 2 weeks before bring them in, I apply neem oil - then again a day or two before I bring them in. Normally these applications keep insect levels in check all winter, though I may see some scale or mite populations appearing toward winter's tail. If it gets too bad, I'll do a neem application & hold out until I get the plants outdoors where the increase in the plant's metabolism and thus natural defenses, along with the increase in beneficial predators, usually completely eliminates the trouble.

    The bio-compounds plants use to repel plants are a by-product of the plant's metabolism. Plants with high energy reserves and plants growing with good vitality are much better protected 'naturally' from insect predation, which is why plants in low light and those that are just limping along are far more likely to be troubled by insects. I very often diagnose the occurrence of insect infestations as the end product of poor cultural conditions, and the greatest, most frequent offender is a poor soil."

    I'm not implying you're using a poor soil; I know you're not, but others might wish to consider the corollary.

    Al

  • krustysurfer
    10 years ago
    last modified: 7 years ago

    there is questionable information about 'azadirachtin'it has been shown to shrink the testes of certain insects...now in chemistry there is something called a 'LD'=Lethal Dose i dont know what the LD for 'NEEM' but i would be wary of eating or smoking anything that has been sprayed recently with neem--ESPECIALLY INGESTING PURE NEEM OIL...just because its natural does not mean safe(apple seeds contain Arsenic eat enough you die)it works as they say but the testing is still out with results not back...be wise we have used it in the past it does work and will knock down pest populations-THE TASTE IS HORRID and you wont forget the taste or smell so easy does it and keep it off of you your clothes and just harvested veggies-or try making up a homemade brew with other essential oils...caution with those too, some oils will kill plants and give you a nice dose of estrogen ...be wise

  • tapla (mid-Michigan, USDA z5b-6a)
    Original Author
    10 years ago
    last modified: 7 years ago

    From the opening post: "Let me preface the following comments by reminding you that the terms "naturally occurring and/ or organic" do not universally mean safe. Pyrethrums, rotenone, and even the very dangerous nicotine are all organics that should be handled with great caution", so clearly no one is suggesting 'natural' automatically = safe.

    I'd be interested in reading what prompted you to suggest neem oil isn't comparatively extremely safe. It's mixed into grains to control damaging insect populations, used in the manufacture of multiple cosmetic products, used in most Ayurvedic remedies, and widely ingested as a remedy for stomach disorders in the East. That doesn't mean I'm suggesting you should eat it; some studies suggest you should avoid ingesting neem oil if trying to conceive or pregnant because labratory rats fed large daily doses had lower conception rates, but I've not seen anything to suggest it's dangerous. As far as I know, there are no government restrictions on the amount of neem residue allowable on crops grown for consumption.

    Al

  • mylespickett
    10 years ago
    last modified: 7 years ago

    I have a question concerning the sensitivity of acers, specifically Japanese maples, concerning the foliage spraying and soil spraying of neem. I sprayed early in the morning (dyna-gro neem) with a maintenance portion of Pro-tekt. Should I still use a separate emulsifier such as ivory dish soap or would adding the pro-tekt be sufficient? Also I have a lot of leaves turning and falling (partly my fault on a few trees from over watering :(, and I live in sunny Arkansas). Would the neem spray be a possible suspect for some of my trees defoliating? If so, would there be any advice on time of year and dosage/application of the neem for the JMs? I know Al is pretty much the container/bonsai/Dyna-gro/everything, guru and knower of all things so I figure Al or anybody else would have some advice on the particular species using neem. Thank you!

  • mylespickett
    10 years ago
    last modified: 7 years ago

    Hah!... First off let me start by addressing yer last statement; if it wasn't for me just stumbling along the forums and reading your posts on containerized plants and fertilization and water retention just a month or so ago, I'm pretty sure all of my trees would be brittle twigs of dieback down to the roots. So far I have around 36 cultivars and a hand full of 2-3 yr old seedlings (green & red). I can't help it! And I can't help that you know you're stuff. :)

    Well, not trying to derail the Post. Yes my soil temps have got to get to fairly high temps in the day, although the pots dont get more than an hour of direct sunlight a day. We are in a statewide drought (not to mention nationwide drought) so weve had temperatures reach 109F this past month and at least half of my trees are variegated so thats my fault on the lack of educating myself enough on the dangers of a southern summer in association with delicate plants. Since we're on the houseplant forum (didnt realize til after my first response, oops! I just clicked a link on another forum and it brought me here, could I use a low concentration of neem on orchids as a leaf shine? I know nothing of orchids but my girlfriend has a few and the thought crossed my mind. And speaking of the "leaf shine" effect, I tried Garden Safe's neem concentrate (which is clarified hydrophobic extract 70%) and it seems to produce a much shinier effect than the dyna-gro... Maybe I haven't been shaking the dyna-gro mix enough? Also speaking of the temperatures, would it be wise to use pro-tekt as i would neem, overcast mornings/evenings? i love the pro-tekt, i have already seen a vast improvement on the health and vigor of my pepper and tomato plants after only a couple of weeks of use!

  • tillygrower
    10 years ago
    last modified: 7 years ago

    I'm spraying my Meyer lemon foliage with Tapla's neem oil formula (above) prior to bringing the plant inside later this month. I thought I read that one should also do a soil drench with the neem solution. If so, can I keep the alcohol as part of the formula, or should it be excluded? I figure the alcohol could damage the roots, but I just wanted to check.

  • tapla (mid-Michigan, USDA z5b-6a)
    Original Author
    10 years ago
    last modified: 7 years ago

    Skip the alcohol if you use it on the soil.

    Al

  • saminah
    7 years ago

    Hello,

    I'm interested in using neem oil as a systemic pesticide. I've soaked the house plants, the tomato, garlic, and tithonia seedlings and the slow starting Lord Baltimore hibiscus. I used 1oz. per gallon. I soaked the potted plants and seedings in a bucket and drained them. I poured four gallons of neem solution on the hibiscus. They look OK three days later. With my confidence boosted I like to know what to expect and how to handle big plants and garden areas.

    • How long does soil drenching take to reach an effective concentration in the leaves of a plant, e.g., tomatoes, sunflowers, a 12' American Cranberry bush, a 40' maple.
    • How do you drench the soil?

    Do you soak the house plants in a pail for 15 minutes or water it until the neem oil solution leaks out?

    How do you drench a 48' garden bed, tall bushes and the maple tree? What about a lawn?


    Thanks, Todd