Organic pesticide for large market garden
We will be planting on about 3 acres this year - tomatoes, squash, eggplant, peppers (bell & hot), mesclun mix and varies others...
Last year we had problems with flea beetles, whiteflies, squash beetles, borers, and colorado potato beeltes and the occasional hornworm (most that we found were already "egged" by the bracchid wasp ;) We used spinosad and diatomaceous earth last year which were somewhat effective. Now that we know our enemies we are focusing on preventative measures (crop rotation, beneficial insect attractants, effective intercropping) but I know that won't be enough. The squash beetle & potato beetles are quite determined, as are the borers (but I know there is not much to do about them so I plan on a weekly sowing of squash & zucchini in different areas).
Diatomaceous earth was effective in controlling the squash beetles but it was very time consuming to apply and our garden is much bigger this year. I will definitely be using a pyrethrin concentrate (PyGanic EC 1.4) and spinosad as needed. There are some other products that seem to have merit - Monterey's 3-in-1, AzaMax, and several oil based products (neem, soybean, mineral, etc) and these claim to prevent disease as well - we had an issue with powdery mildew (though that was certainly due to use of an overhead sprinkler when our burried irrigation line crapped out) and bacterial wilt.
Anyone have experience with these products and care to make a recommendation one way or the other? I have no problem combining several methods, I just want the most effective but must be organic as we are in the process of becoming certified.