I've not seen it done. It is never a good idea to mix together two substances that chemists won't.

I tried neem last year on the cuke beetles, without much luck. They killed my whole cuke crop.

The cuke beetles haven't yet arrived, but I've set out some trap plants and companion planting to try to ward them off/tempt them to more delicious plants.

However, one of my trap plants has been invaded by squash vine borers, something i've never had before and it will probably die.

I've been thinking for quite some time about spinosad, which is some kind of fermented something and is considered organice. It's supposed to work on cucumber beetles and not hurt the beneficials.

I came to post a thread about this product and see what people think. It's kind of new. So you might be interested in the thread.

I agree with Kimmsr, not a good idea to be mixing products. Be careful with the neem...it kills bees and other beneficials.

Be careful with the neem...it kills bees and other beneficials.

No, neem oil doesn't kill bees. Bee keepers spray their bees with it to control mite infestations. Neem oil only kills insects that eat it when they eat the plant sprayed with it.

There are commercial products out there which contain neem plus other things and some may have soap mixed in to make the oil mix with water better and these other substances may kill bees and beneficial bugs, but neem oil does not.

timshaw, neem products are very bitter and dissuade the target from eating. Bt is a bacterial agent which affects the gut of the caterpillars of moths and butterflies ONLY. So we have two products, one of which must be eaten and the other which discourages eating. Add to the mix that one of the targets is the larva of a BEETLE, protected within the stem of the plant. There might be another formulation of Bt which is effective against the larvae of beetles; I just do not know. But just in case you are in any doubt, I certainly would not mix the two products.

Hi all thanks for the responses,
Well if todays current crop of cucumber beetles and flea beetles are any clue it doesn't work. The vine borers (? I'm not completly sure thats what they are but they are green wormsand have bored into the cucumbers not just plants) seem to have gotten a bit better.
ronalon, your reasoning for not using the two bio insecticides makes perfect sense. But on one point I have to dissagree. Squash vine borers are the pupa of a moth that looks very much like a wasp (been googling this for about a month looking for an organic way to deal with this and no luck so far. But just wait!) Anyway still working on my soil and learning to be patient.
Thanks again, Tim

Have not mixed neem with BT but have used products with neen and natural pyrethrins I Know this will Kill many Insects Benifacials included but it brakes down quickly and has less of an effect on good bugs than some other pesticides.

timshaw, thanks for reminding me that I sometimes suffer from 'foot in mouth disorder'. The fact sheet from Ohio State University confirms that the squash vine borer is indeed a moth. It does also state that the larva enters the stem near the base within hours after hatching; this requires almost exquisite timing for the application of any product except a systemic.
Thanks once more for your response.

i spray my tomatoes, peppers, basil, kale etc weekly with BT AND Neem oil mixed together in a spray tank. i also use vinegar to ph adjust the solution the the low 6's and a dab of dish soap to use as a surfacant(sp?). use the bt and neem both at full strength but spray only in the evening or dark/cloudy days. if u spray more than once a week with neem oil you will see some burning. use the wand sprayer and get deep into the plant for maximum coverage.

to figure out how much solution u need to make first just do a test run with plain water.

i spray my tomatoes, peppers, basil, kale etc weekly with BT AND Neem oil mixed together in a spray tank. i also use vinegar to ph adjust the solution the the low 6's and a dab of dish soap to use as a surfacant(sp?). use the bt and neem both at full strength but spray only in the evening or dark/cloudy days. if u spray more than once a week with neem oil you will see some burning. use the wand sprayer and get deep into the plant for maximum coverage.

to figure out how much solution u need to make first just do a test run with plain water.

People that spray that often, once a week, with anything need to take a good look at their gardening practices to see what they are doing wrong.

http://www.ublcorp.com/files/Biological_Insecticides.pdf check out this article you can mix Neem with BT and insecticidal soap

Hey Kimm: Spinosad has a 7 day residual for at least one insect, does that mean if one has to use it to get 2 or 3 successive generations of an insect they are all screwed up in their pest control strategy? How about to control an insect whose egg hatch period can last for 2 weeks?

If you need to spray poisons, natural, organic, or synthetic, often you need to look at your gardening practices to see what is not working. Many of us that have practiced organic growing for years have seen a decrease in insect pest problems as our soil became healthier and grew healthier plants. Spraying those poisons less often allows the beneficials, predators, to work for you in controlling any insect pests that might appear.
This is not to say we do not have insect pests. but that spraying poisons should not be something done regularly. That practice is necessary in a garden that uses synthetics.

@kimmsr

Bt is not a poison. You don't seem to know much about organic gardening.

Neem oil is also not a poison.

Squash vine borers do not give a rat's ass if your soil is healthy, and published studies show there are no predators that can keep them under control. You may not live in an area where SVB inhabit. In which case you have no idea what you are talking about.

Ive called my local university co-op extention on this as it doesnt seem as if anything that will supress something as small as mold and spores, would easily be killed by an oil application. The catapillars need to eat to have bts and other bacterias, g if the get hit by oil that may very well kill them or cut back. The bt breaksdown quickly in sunlight. So it is better to spray that first a day or two before oils at evening giving the little boogars time to injest it. Bt takes time to act within. It takes about 2-3 days to kill. In the next spray if you must spray oils then spray then. Or you can find a biological "pre-emergent" (pe) there are organic ones. A few days after that up to 7 days release beneficial insects such as wasps, pirate bugs, mealy bug destrpyers, what ever pest you need to control. There are many. Disease is now the biggest threat & there are beneficial sprays just for disease.. oils work ok but there are a few beneifial baterias that kill and supress.

Unfortunately, you have to spray more than once but with this prescription you wont need to spray as often. Ive only sprayed once since june, i live in a coastal area lots of fog and wet. Now today i have to spray...two months between sprays darn well worth the cost and time.