Natural/Organic Fungicides and Pesticide
Firstly, there is a difference between natural and organic, but for those who are attempting to avoid harsh chemicals -
I came across this (bloggish) web-site which has a wealth of info (by text and links to other sites) addressing fungicides and pesticides.
I know for a fact that soapy water is sure death for aphids, but was wondering if anyone has successfully used any of the other teas/potions? Particularly in the case of a fungicide, how long/many applications need to be made before results are seen. It's my understanding that these applications require much more time than their chemical counterparts.
It doesn't work worth squat on aphids, but food-grade diatoamceous earth is a great killer of crawling bugs like earwigs and sowbugs and actualy, just about any of the garden pests except aphids. The ground-up fossil shells pierce the outsides of bugs and dessicates them.
Just make sure you get the food grade rather than the pool filter grade. The pool stuff is more full of asbestos than the food grade, which you can usually find at feed stores, or failing that, online.
I don't think I'm seeing the right site. Your link goes to a Google Groups discussion, but I don't see teas/potions other than soap spray and that horrid Listerine/tobacco concoction. (Don't do that. Really.)
A spray or paste made from baking soda can be used to treat powdery mildew, which is a common problem with peas and cucurbits (mostly cukes, and a few types of squash). (More here: http://attra.ncat.org/attra-pub/bakingsoda.html). Copper and sulfur fungicides are reported to work too, but they're more toxic. (More here: http://vegetablemdonline.ppath.cornel...).
I've tried the baking soda. Never had much luck with it. Part of it is that powdery mildew is largely a problem of condition -- humidity and lack of air circulation, primarily. No amount of fungicide is going to cure that problem if you're in a humid climate and your pea plants are climbing up a wall or wooden fence.
The best way to head off powdery mildew these days is to buy plants resistant to it. (Edited to add: Also, make sure you don't water the leaves of the plants. Water at ground level only. A soaker hose is great for this.)
There are other fungal infections that affect tomatoes and peppers. Fortunately, knock wood, praise the gods, I've never had to deal with those, so I can't report on what works and what doesn't.