Posted: 20/08/2012 at 19:06
Oh dear, so many problems.
First of all let me say that this year has been a very trying time for all gardeners, especially in terms of wet weather, pests & diseases and sadly some of your problems could have been avoided or at least minimised by good cultivation.
I've heard of growing sweet peas with climbing beans, but it isn't something I've ever tried. In a good year you may well get away with it, but I can see that it would be problematic this year.
All legumes (including sweet peas) are prone to mildew, even more so this year where the mildew spores flourish in warm damp conditions. Good ventilation between plants is essential, so (as you will understand) growing between beans will just exasperate the problem.
As I said earlier, I don't grow beans & sweet peas together, therefore I can't be sure if the present mildew will infect your beans.....hopefully not!
I can't claim to be a totally organic gardener, I do always refrain from spraying food crops, although I have no qualms about spraying my sweet peas with 'Pravado' to zap aphids....one application ensures aphid free flowers for 6 weeks.
Sorry, I have no info on a baking soda/liquid soap mix.