Personally, just the mention of Dr Phil Callahan is two strikes against you, kimmsr. I used to think you were a smart guy (heh, heh). But really, I think Callahan had some wrong ideas. This is not to say that his suggestions were not worthwhile, I'm saying that his reasoning as to why they worked was incorrect. I don't know what the answer is, but I'm convinced he doesn't either. I'm not familiar with the others you mentioned but one with the book is up on my browser. I just need to find time (maybe after taxes). Generally I agree with kimmsr that healthy soil is necessary for healthy plants. If you don't have healthy soil, you are fighting an uphill battle. I've lived in Riverside, Downey, Hawthorne, and Pomona. When I lived in Hawthorne (1975-1979), there were still agricultural fields in Torrance back by the malls. Bet those are gone now!! But any of the soils in any of those places would be vastly improved with alfalfa pellets or corn meal applications. Simply stopping the use of chemicals for control of fungus, weeds, and insects goes most of the way toward good soil health. Proper watering, mulching or mowing the grass tall, and organic fertilizer is all you should need after that. And kimmsr will say you don't need the fertilizer. That may be a goal, but I continue to need it to get the dark green in the grass and fruit on my lemon.

There is mounting scientific evidence that the use of compost tea can help suppress some diseases and insects that affect plants. When looking for real evidence on compost tea, or any other product that you have heard about don't forget that Google has a feature under the more button at the top called scholar. If you use this feature you can filter out the sales pitches and read the science. Here is an overview of what I know and have learned about compost tea. Compost tea is not a miracle cure for all diseases or pests. Evidence does show that it can suppress certain diseases, insects, even root nematodes and possibly within an acceptable level in some cases. Most fungi infect plants when the leaves are very young and vulnerable so applying compost tea, or for that mater any chemical control, after the symptoms are seen is usually not going to give you any control. Even if compost tea does not give you the desired control, it can do no harm and will supply your plants with nutrients. Compost tea seems to work better the fresher it is. There is still a great deal of research to be done on compost tea to determine how it works, on what, timing of application, production methods, how to keep it from loosing its potency over time, and a lot more. By all means add compost tea to your arsenal of things you use to protect your plants under an integrated pest management approach, but don't expect it to cure all that ails. Remember that healthy plants can grow and produce fruit with a variety of diseases and insects, depending on the pest and the level of infestation. There are also new organic fungicides such as Actinovate that use beneficial bacteria to control fungi that are showing promise, but the jury is still out on how good they are. Again do your Google scholar research on these. Also Oil(Neem or Horticultural), Soap, Bt, and Spinosad, for insect control are all accepted as organic.

Campanula, you are right to be concerned. There are unwanted consequences to every bio-control agent out there. I work in ecological restoration and we really dislike preying mantises and crab spiders, both non-native insect eaters, and we aren't wild about the store-bought ladybugs either as they are an Asian species and they appear to be pushing out the native ladybugs. Things like ladybugs and mantises are generalist predators - they eat whatever they can fit in their mouths. Not good for native species! Parasitic wasps tend to be more specific but still no guarantees. We really dislike Bt as well as it kills all caterpillars - the pestiferous ones and the native butterflies all. My boss doesn't like any bio controls - bugs introduced to control invasive weeds or insects. They will eat native species in the same genus as the target pest, for the most part. The USDA does run tests before it allows these bio controls to be released but their focus is not the same as ours - they support agriculture, and native ecosystems are expendable. Ditto for the EPA's tests of biological pesticides - they don't run them long enough or thoroughly enough to uncover all their negative side effects. The needs of agriculture trump environmental health. But, there are no undisturbed ecosystems. Our gardens are all highly disturbed. Garden plants usually are not native and are planted in disturbed, amended soils and watered with imported water and fertilized with imported materials. Even native plants are exposed to imported diseases and pests and unnatural conditions. I feel it's unfair to the plants to do nothing for them when diseased or attacked by insects. I just keep in mind that there are NO 'safe' pesticides - all have unintended effects on nontarget organisms. And bio control agents won't willingly starve to death once the target pest is gone - they'll eat something else if at all possible. I use cultural controls as much as possible, and companion planting to encourage a mix of beneficial insects and predatory birds. I've also come to the realization that perhaps I should leave food production to the professionals! there's plenty of small scale producers selling at the local farmer's market and I should be supporting them since they do a much better job than I ever could in my little urban backyard.

My getting horse manure mid-summer this year was worth it: Only 1 rose-slug out of the entire garden (50+ roses), that's on the hill where I could not apply horse manure. Previous year of NO horse manure I had at least a dozen rose slugs. High-phosphorus ATTRACT pests. Yves Seedling got DOUBLE-DOSE of Dr.Earth NPK 4-10-7 ... I was absent-minded so I applied that twice. That's the only rose which was attacked by thrips ... I killed 5 thrips on that rose, after seeing one deformed bloom. Yesterday I saw one grasshopper on that rose, so I chopped that pest into half with a scissor. I was cutting blooms for the vase, so I inspected all my roses: none of them have grasshopper, except for Yves-seedling. Yves Seedling is in its 3rd year, no thrips whatsoever in previous years .. it's a dark-red rose. Re-post the info. Here's an Abstract from Cornell University, entitled "Effects of manure and chemical fertilizers on insect pest populations on collards." http://www.researchgate.net/publication/223371840_Effects_of_manure_and_chemical_fertilizers_on_insect_pest_populations_on_collards Department of Entomology, Comstock Hall, Cornell University, Ithaca, NY " This proposition was examined using collards grown in five treatments: two with fresh manure at two levels (12 and 220 ha−1); one with ‘sheet composted’ manure at 220 ha−1; a chemical fertilizer treatment (785 kg ha−1 of 13:13:13 NPK); and a control treatment with no added nutrients. Population densities of two flea beetles and two lepidopteran pests were monitored weekly. During population peaks, flea beetle densities were significantly higher on plants receiving chemical fertilizers than on plants receiving similar amounts of macronutrients from manure. Flea beetle, imported cabbage worm and diamondback moth densities were significantly higher on untreated plants than on plants receiving any added nutrients. Flea beetle densities were also significantly higher on plants grown with ‘sheet composted’ manure than on those grown with fresh manure. " *** From StrawChicago: As to rose-midge, the only time I had that was when I did my oat-meal experiment in 2013 fall: mixing oatmeal with fluffy potting soil, and topped Golden Celebration with that in the fall. That created a perfect moist & fluffy environment for rose midge to hatch. I saw midge flying around that rose, plus deformed blooms, so I read Cornell University research which stated that too dry, or too wet would stop midge. So I put my soaking-wet-clay on top, and FLOODED that area many times per day. That took care of rose-midge for good. No other roses affected, and no midge in my 2 decades of growing roses. This year I topped my roses with DRY & alkaline RED-LAVA-ROCK and pea-gravel. Here's a good article on Rose-midge control: http://www.pghrosesociety.org/rosemidge.html "The only reported effective non-chemical control for rose midge would be daily removal of affected new growth tips and destroying the debris. This prevents of larva from dropping to the ground and pupating into new insects. Do not compost the remove plant material for this will allow the life cycle to continue in and around your garden. This requires diligent daily inspection of the new growth to detect the infestation and remove the plant part before the larva (sometimes referred to as maggots) fall to the ground. There is some anecdotal reports that removal of any mulch and loose soil around the plants in late fall will remove the embedded larva which burrows about 1-2" below the surface. Again this material must be removed from the garden or anywhere within 150 feet to prevent return of the insect. The only scientific study published in the horticultural literature on in subject of rose midge control appeared in 2006 authored by Dr. Janice Elmhirst ... The two biologicals tested are commercially available, one being AVID (with the active ingredient abamectin derived from the soil microorganism Streptomyces avermitilis and the other DOKTOR DOOM®, a ready to use permethrin formulation. The predators were a nematode (Steinernema feltiae) and a predatory mite in the form of an unidentified Hypoaspis species. The chemical control was Matador (lambdacyhalothrin), which is similar to the active ingredient in the Bayer chemical products mentioned earlier. The results of this study were interesting in that the predatory insect approach actually had a higher level of midge damage than the untreated controls. The best result came from the Doktor Doom product with less than 2% damaged rose growth. The next best was the chemical control with approximately 4% damaged tips. The Avid did better than the control but not by a significant amount." http://www.pghrosesociety.org/rosemidge.html