Copper wire

How would stringing copper wire above spuds prevent blight??

Glad you asked, I thought I was being daft.

It's the people who come up with this stuff who are being daft

Copper dissolves onto plants / plants take it up, and have resistance. Dissolving would happen in rain, which is when blight is prevalent.

Just guessing though!

Ok. I'm not a plant biologist but copper ions are instrumental in fungus control including blight. In the original thread, Nicos explains how French growers (presumably of grapes) string copper above their crops. The idea is that rain dissolves the copper and then that falls on the crop below. There was some debate on the thread as to just how little copper is needed to control blight. Obviously, we have a very different climate to the majority of France and this could affect just how effective this method might be in a more maritime climate.

I'm sure anyone interested and with the time will trawl through past scientific papers and archived articles but for people who do use copper sulphate spray and now can't it is perhaps an option worth investigating. For me it falls into the category of "it might be "organic" but that doesn't mean it's nice.

I should probably have pasted a link to the original thread to avoid confusion :-/

http://www.growfruitandveg.co.uk/gra...awn_84434.html

Cheers :-)

The problem with this idea is that Bordeaux mixture is more than just copper and, in order to be effective, spray coverage of the foliage has to be complete, including the underside. A few drips from an overhead wire, even assuming it has copper ions dissolved in it, would certainly not do that. Sounds to me like the idea that blight can be controlled by spraying with milk as the calcium in milk creates an alkaline environment which the fungus dislikes. Unfortunately milk is acidic (lactic acid) and it would have the opposite effect.

The point is that the whole discussion comes from Nicos' observation of local practice in France:-

What we don't know is how frequent or serious the threat of blight is in that environment compared with Britain or whether this is a bit of a preventative which is then topped up with spray.

As VC has pointed out (on the other thread) Bordeaux Mix is still available, so this may be a bit of pointless discussion unless or until someone does the background research and trials the idea.

The milk acid vs alkaline debate is as old as chemistry itself, as it's not about the ph of the liquid it's about what happens after it's metabolize or broken down. Unfortunately it all depends on several things, such as freshness, type of milk, level of pasteurisation and fat content and how our bodies and other things react to it. It can be either neutral, acid, or alkaline forming depending on the circumstance. At it's worst milk is very slightly acid forming, and at it's best slightly alkaline forming, so I can't believe that the ph change is why milk would affect blight in any significant way.

However milk does contain calcium and potassium phosphate. Both of these are particularly effective supplementary fertilizers, especially for toms. They strengthen them against disease and anyone who has ever had blossom end rot in crappy soil will attest to the value of calcium. Potassium phosphate is also an antibiotic and a fungicide and would help halt, or at least slow down blight.

It's not a full blown magic solution, and it's not one I even use. But there is at least some scientific back up to why it might help blight.

As for the copper wire, hmmm... dunno. I find it hard to believe the level of dilution would have any affect. But I am happy to be proven wrong and string up copper above my potatoes and toms! But you'd have to do a pretty in depth study for me to buy into it :P Last year I got a solar radio and played radio 2 to my toms. They didn't get blight. Coincidence, or evidence that radio 2 has anti fungal properties?

We were told about this by an organic brewer of British beer. He used it on his hops after a local had said they'd been using copper wire from stripped electricity wires over spuds, tomatoes etc.
And apparently it worked.
He won loads of awards for his beers.

As you say- it's worth a trial!

I just had a light bulb moment!

I recall someone once saying that copper pennies pushed into the stem of a tomato plant helps prevent various diseases ...and then another recollection about our plumber friend saying you shouldn't really use plastic water pipes to showers/drinking water as they don't have the same antimicrobial/antibacterial effect as copper pipes do.
And so- I have had a quick gooooogle and come up with this....

Antimicrobial properties of copper - Wikipedia, the free encyclopedia

might be worth researching further?