BT vs. Neem oil

[amont009]

So I've been having a small problem with gnats and caterpillars. I've managed to control most of the gnats with cinnamon, chamomile tea, peppermint tea, and changing the time that I water my plants. I have yet to find anything useful to take care of caterpillars and they ate up my roommates geranium which she left under my care for the summer.

I have only briefly read up on BT and Neem oil. I know both are used to control pests, but I honestly don't know which one is better or if they control different pests.

Also, I would like to keep my garden as organic as possible. So any information on the these two sprays, or perhaps something better, would be greatly appreciated.

[rainbowgardener]

Bt is a bacterium (bacillus thuringiensis) that is specific to caterpillars and other larval forms. Sometimes you have to know what your pest is -- I believe the strain of Bt that works against mosquito larvae for example doesn't necessarily work against the caterpillars.

Neem oil is a general insecticide that disrupts the systems of chewing and sucking insects that ingest it. It does not kill them on contact like poisons do, but works more like a hormone that disrupts their functioning so that they can't eat or mate and eventually die. It works against a broad range of those chewing/ sucking insects and also has fungicidal properties, so works against some plant diseases.

Neem is not supposed to be harmful to pollinators or to predatory insects (like the wasps that parasitize leaf eating insects), because they wouldn't ingest it.


Either one would probably work for you. On general organic principals, I tend to choose the smallest guns first - the most specifically targeted, least disruptive in the environment. I think you are doing well to keep your garden organic.