After-thought [member=23109]Mad Goatwoman of Madeley[/member] :
As you will know, there are plenty of household (organic) products that can provide some or good defence against plant fungal (& viral) diseases and then there are some (organic) not so "household" products besides the 'approved' commercial offerings. (Commercial 'approved' offerings have obviously gone through extensive trials, whereas the non-commercial offerings have not.) Whether any one of these would help (along with the recommended pruning) is unknown, but surely gotta be worth trying a spray solution from one or more of, if only to make the PLC spores have to work harder to infect your nectarine again. In no particular order:
- Bicarb' of soda (not baking powder!)
- Calcium chloride or nitrate
- Cinnamon powder or oil
- Epsom salts (Now, I understand this contains a sulphur compound so it would, perhaps, be my 1st choice.)
- Garlic
- Chilli
- Milk (!) - any sort of milk.
- Mustard oil/greens (Latter steeped 50% in water. Can't recall whether needs to be diluted afterwards, but I think so)
- Neem oil (added via a warmed partially diluted/emulsified starter mix to add to final spray mix)
- Potassium bicarbonate
- Urine (!)
Even a seaweed spray solution or worm-cast liquor might help in some way.
Spray recipes/recommended dilutions readily found ont' web.
Additions of vinegar, veg' oil and liquid soap (not detergent) might also be considered with latter two helping with adherence/penetration.
Hope it doesn't seem like I'm trying to teach Granny, but I'm a firm believer in trying everything when the alternative 'approved' chemicals might need much more careful/onerous handling precautions (for health reasons or even environmental reasons) although they might be considered to be 'organic'.