Organic spray for blight

shawnee

Anyone know of an organic spray for potato blight

My Potatoes

I don't think there is an "organic" spray in the true sense of organic gardening. However, there are chemical sprays that are regarded as acceptable by the organic community. The most well known are Burgundy Mixture and Bordeaux Mixture. It's regarded as kosher to use these three times in one season, or a fourth time with permission, or something like that.

It's a bit spoofy. A bit like the organic slug pellets.

I used Burgundy Mixture myself:
CuSO4 : Na2CO3 : H2O
1:1.2:100

redser7

An argument against those is that the copper is not good for the soil life as it can build up. And also enter ground water. Always comes down to a moral dilemma in the end with any kind of ***icide. Or money if you grow commercially.

redser7

My Potatoes wrote: »

I don't think there is an "organic" spray in the true sense of organic gardening. However, there are chemical sprays that are regarded as acceptable by the organic community. The most well known are Burgundy Mixture and Bordeaux Mixture. It's regarded as kosher to use these three times in one season, or a fourth time with permission, or something like that.

It's a bit spoofy. A bit like the organic slug pellets.

I used Burgundy Mixture myself:
CuSO4 : Na2CO3 : H2O
1:1.2:100

So you mixed those yourself? Where do you get the ingredients? Do you think it's as effective as Dithane?

My Potatoes

Mixing it is straightforward:
https://www.facebook.com/MyPotatoesIE

Got the copper sulphate in the chemist and the washing soda crystals in the supermarket.

I only used Dithane in one season. I've found them both equally effective.

redser7

Great, appreciate it.

amandstu

I think it is best to mix it yourself.At first I bought it ready made and then I read that it goes off (is less effective) with time.

So now I make it to order and am happier with the results.

I only bother with the maincrop though.

My recipe is just copper crystals and builders lime - its all I 've tried along those lines .

-although I have also tried a very weak solution of asprin with a little Fairy and some water.It needs to be applied when the plants are just starting off and reapplied fairly regularly.The idea is to build up the resistance of the plants (it does sound unscientific )

I had great success with it but didn't have the discipline or perseverance to repeat the programme the following year.

Macy0161

amandstu wrote: »

I think it is best to mix it yourself.At first I bought it ready made and then I read that it goes off (is less effective) with time.

I don't think you can buy ready made anymore - EU testing rules or something like that, and since no holds the patent no one will front up the money if I recall correctly.

On the organic question, that's up to the individual really. But these mixes (and the slug pellets) are good enough for otherwise organic zealots.

My Potatoes

Macy0161 wrote: »

I don't think you can buy ready made anymore - EU testing rules or something like that, and since no holds the patent no one will front up the money if I recall correctly.

Vitax sell Bordeaux Mixture (the mix with lime):
http://www.vitax.co.uk/home-garden/vitax-bordeaux-mixture/

Not sure about Burgundy Mixture (the mix with washing soda).

hfallada

Copper sulfate as far as I know is banned from the EU as it is a heavy metal and causes issues in the body

keltoms05

hfallada wrote: »

Copper sulfate as far as I know is banned from the EU as it is a heavy metal and causes issues in the body

So is dithane still available or is it banned? have a small veg patch and want to protect it from blight but dont fancy putting copper sulphate near them!

redser7

Well if you have concerns about copper sulphate you should definately have more concerns about dithane.

keltoms05

redser7 wrote: »

Well if you have concerns about copper sulphate you should definately have more concerns about dithane.

So do u think an organic spray would be the best then?

redser7

Sorry i havn't tried the organic approved sprays. I was just talking from an environmental point of view.

keltoms05

redser7 wrote: »

Well if you have concerns about copper sulphate you should definately have more concerns about dithane.

So would u recommend an organic spray then?

redser7

Both would help keep blight off long enough to get a crop. Whether you use one or the other or any at all is up to yourself really. Do some research, people are concerned with the dangers to health and the environment of using them.

Macy0161

keltoms05 wrote: »

So would u recommend an organic spray then?

I haven't used it, but I'm sure I've heard people using a bread or baking soda mix for blight and other fungal diseases. My notebook is at home, but I probably have a recipe from a GIY meeting.

As I mentioned, plenty of otherwise organic gardeners/ commentators seem to be ok with one of the mixes - I think one of the organic places were on Garraí Glas last week showing Síle how to mix and use it!

CorsendonkX

keltoms05 wrote: »

So is dithane still available or is it banned? have a small veg patch and want to protect it from blight but dont fancy putting copper sulphate near them!

Still approved, they reformulated and applied for a new registration in Ireland.

http://www.pcs.agriculture.gov.ie/getprod.asp?prod=6490
http://www.pcs.agriculture.gov.ie/getprod.asp?prod=6692

Part of the problem in Ireland isn't that a pesticide is banned, the chemical company must pay and go through the whole registration process and for niche crops it just ain't worth the hassle when you compare it to possible sales.

glanman

Hi applied A burgandy mixture at weekend for first time. wondering is there a time period for no digging as there is with other sprays

amandstu

glanman wrote: »

Hi applied A burgandy mixture at weekend for first time. wondering is there a time period for no digging as there is with other sprays

Not sure. By the way I thought once the blight got into the crop you would need to cut down all the haulms pronto.

If your leaves have not been affected ,have you sprayed the bare ground in addition to the leaves? i heard you should.

Another tip ,I was told/read that those mixtures did not keep very well
(I understood it meant they somehow went stale in the container or at least that you had to use it immediately when the water had been added)-so I buy my own
copper crystals and lime and mix them to order (I think Burgundy has a third ingredient -is it Fairy liquid?)

glanman

had been using a conventional spray before this but that is finished so moved over to this now. hadn't seen any blight damage to this point in British queens. dug one stalk of golden wonders last week and were fine but more growing left. also dug caras and they are spot on, they are fairly blight resistant though. yesterday and today are prime blight weather so applied it Saturday when dry.

have bluestone and bi carb in seperate bags so will see how it keeps i suppose. bought them in local vets shop.