Hence, adding an insecticide/fungicide preventively is for me a no-no, especially one like neem where you often don't really know what's inside and if or if not. Neem cake is a byproduct and I doubt that anyone is determining what's inside; one time you get the killer stuff, the other time it's just some plant fibres......
Neem on the other hand lacks longterm studies and a lot of other evaluations, half the EFSA file is 'data not available', 'data gap', 'no study available', 'no reliable study submitted' and so on... Additionally, many neem products are not well defined and at best standardised for azadirachtin A but not the other roughly 300 constituents therein. Apart from azadirachtin B, nearly non of these compounds has ever been studied!
If you look at neem oil products for domestic animals: Most are not standardised and (fortunately) are often manufactured in a way that they do not contain noteworthy amounts of azadirachtin derivatives (hence no toxicity but also no effect).
As neem oil is one of India's main natural resource, a heavy financial boost to the ecomomy, and makes them independent of big agrochemical corporations they do obscure negative effects on their population. You should have seen the documentary about that village where nearly all children were sick, deformed, retarded etc... reminded me of the good old days of DDT. Besides that, I have a colleague who's heavily involved in third world aid organisations who confirmed this sad 'story'.
I did my master thesis on anti-cancer drugs (paclitaxel, epothilones etc.) wherein we examined their effect on gene transcription in human cell lines using PCR. I also tested azadirachtin A. IIRC it does not show a higher acute toxicity than the others but heavily messes with gene transcription. Only based on these data I would rather get a chemotherapy than taking neem oil!
So, go on using something that you don't know rather than something you do know and hence can use appropriately. Your choice .
I quote myself:
Hence, adding an insecticide/fungicide preventively is for me a no-no, especially one like neem where you often don't really know what's inside and if or if not. Neem cake is a byproduct and I doubt that anyone is determining what's inside; one time you get the killer stuff, the other time it's just some plant fibres...
Don't know bout you all, but best tasting flowers comes from nftg and full spectrum lights. Seen it in few Grows best nutes there is. Nftg is unique.. if you ain't ran it you ain't got a clue. $ yes.