[miguelg]

Hi,
My Red Baron onions, spring planted and heat treated are starting to bulb up, however they are also starting to get mildew which affected most peoples autumn planted onions. What to do? Leave them alone or water them to get a bit bigger? I suppose storage is out the question too?
Thanks.

[Snoop]

Have you thought about using a fungicide? Where I am, copper-sulphate powder or wettable is popular.

Edited: to add the question mark. Note to self: read before sending.

[miguelg]

You have probably guessed I am Spanish, by parentage and I do remember him using that, can you get it in the Uk?

[Snoop]

I think so. Ask on the forum, someone's bound to be able to tell you. Not sure if there's a special brand name or anything. Either that or try a garden centre or hardware/dry-salter's shop.

[Goosegirl]

Vitax do a general fungicide called Bordeaux Mixture based on copper sulphate. As far as I know, it should be safe for use by the general public. If you can get hold of some, keep it in a dry place as the crystals absorb water very easily.

[simonwatson]

I think Bordeaux Mixture is no longer available for sale and will be illegal to use after Feb 2015.

[DD.]

Not according to this:

http://www.gro-welldirect.co.uk/blog/2013/05/vitax-bordeaux-mixture-statement/

and you can still buy it on Amazon, although it sounds like some stuff I'd sooner not put on my veg!

[Snoop]

Copper-sulphate is accepted as an organic fungicide here. I have to admit it's overused by some of the old boys round here, but I'll be sprinkling some on my tomatoes, onions and melons after the recent downpours.

Safety period according to the packet I've got is three weeks. I use it once over the course of the year about now and you certainly wouldn't want to use it often or eat the produce before the three weeks is up as it is toxic to both plants and humans in excessive amounts. This link might be useful:

http://homeguides.sfgate.com/effects-copper-sulfate-plants-27633.html

[JayG]

Copper-sulphate is accepted as an organic fungicide here. I have to admit it's overused by some of the old boys round here, but I'll be sprinkling some on my tomatoes, onions and melons after the recent downpours.

Hope that's sprinkling as in spraying, rather than sprinkling as in powder (or crystals?)   

[simonwatson]

Not according to this:

http://www.gro-welldirect.co.uk/blog/2013/05/vitax-bordeaux-mixture-statement/

and you can still buy it on Amazon, although it sounds like some stuff I'd sooner not put on my veg!

Aha. Looks like it'd seen have of the story, not the whole thing. Thanks DD.

[Snoop]

Hope that's sprinkling as in spraying, rather than sprinkling as in powder (or crystals?)   

Actually, I have both, powder for dusting and wettable form for spraying. Both are sold here. I bought the wettable last autumn for problem quince trees but have never used it. To be honest, I like the idea of wettable as it's more likely to stick to the surface, but on the other hand you're applying more water to the surface. Wettable is usually sold here for fruit trees for applying in the autumn or very early spring depending on when people prune. The powder is sold for allotment use. The wettable form is also used for the vines for winemaking.

I'm only reporting what happens here, not what's ideal. I'm always a bit shocked when a friend of ours occasionally presents us with tomatoes with a bit of blue on them. We don't eat them. He's getting on for eighty, is very healthy and active and still has all his marbles and thinks there's nothing wrong with it, especially as it's accepted as "organic".

[miguelg]

Interesting, thanks everyone. Looks like its a little late to do anything now but I might purchase some for next year. As for watering I guess the coming rain will see to that.