Is It Blight?

[BertieFox]

Blight already?

After sunny warm weather for ten days or more, we had a thunderstorm on Friday and then rain last night and this morning.
I've just gone to check on the potatoes which were growing so well last week, only to find an entire bed of Linzer Delicatess and some others with foliage rotting and going brown. Surely this can't be blight already?

I have been 'earthing them up' with grass cuttings but would imagine the blight came in the heavy rain. But what should we do now?

Few of the potatoes seem to have much more than a few pea sized potatoes so far, but I am sure this will spread to all the healthy plants. Is it too late to spray with Bordeaux mixture? And what will happen to all the young tomato plants I have just planted out?

This seems like it's going to be a disaster, especially as the weather is due to remain showery for another week.

Any suggestions about how to minimise the disaster would be welcome.

[WendyC]

Does seem a bit early but can't think of much else that causes such rapid devastation. Did you take any photos? You could spray your tomatoes with Bordeaux mixture to try and protect them. I think I would clear the foliage that has gone, it's not doing any good even if it isn't blight. You could also spray any unaffected foliage and wait and see what happens. How disappointing.

[VirginVegGrower]

Is it Blackleg? Where's the damage?

[Nicos]

There was a blight warning in Cheshire a couple of weeks ago.
It takes the fungal spores about 10-14 days to affect the plant- so yes it is possible it could be blight .

Do the leaves have dark splodges on them?

[SarzWix]

That seems incredibly quick! The first thing to do is get rid of the damaged foliage, pronto. Then spray everything else with Bordeaux if you're planning to use it. You could try protecting the tomatoes with a hastily rigged up cage of some sort, covered with polythene or perhaps fleece stops spores? I don't know.

Have you had damp or excessively humid weather before the thunderstorm? It takes at least 2 days of warm and humid weather for spores to become active, and then time to do the damage?

[Thelma Sanders]

or was the storm so heavy that the sheer weight of the rain did the damage?

[redser]

Blight warning in effect in Ireland as of today. Humid and wet weather due over the next couple of days. And so it begins. Feel for you Bertie, lost everything last year.

[PyreneesPlot]

I've what looks like blight on the tomatoes - stripped them of almost all their leaves earlier in the week and sprayed with Bordeaux mix.
We've gone from torrential rain and 9 degrees in the day to torrential rain and 13 overnight and 32 during the day in just a week.

[BertieFox]

Thanks for the helpful advice. I do think it's blight as the weather was very humid and warm just before the rain, which continued yesterday.
I will get out today and cut off and remove all the infected foliage, especially as the most affected are the Linzers. I might be able to save some of the others if I spray. I will get some Bordeaux mixture and give the tomatoes a splash as they haven't been affected yet.
Thanks again for the advice as my immediate reaction is to throw up my hands in horror and do nothing. At least it sounds like I might be able to retrieve something if I get out there and do something.

[SarzWix]

With blight, the very worst thing you can do is do nothing, it just gives it more time to proliferate You'll have to be ultra vigilant, chopping off and burning any affected foliage that appears from now on. A thick mulch on your remaining spuds would help to protect the tubers from any spores washed onto the soil too; straw/grass-clippings/shredded paper or even plain cardboard.

[Olorin2001]

I recently registered with blightwatch dot uk, figuring it would take the guess work out of whether and when to spray. It was free so there was nothing to lose. On Thursday I had an SMS of a full Smith Period allert and sprayed my plot and the neighbours with Burgandy mixture.

[SarzWix]

Blightwatch.co.uk - the essential service for professional potato growers is a really useful service, even if you aren't planning to spread it alerts you to keep your eye out for any signs. But, it's not much cop for those who live outside the UK. It sounds like BertieFox has had blight conditions long before us.

[daviddevantnhisspiritwife]

We've had 3 full smith periods in our postcode area over the last week or so. I have been keeping an eye on my potatoes. The alert covered a wide area of Swansea SA1 - SA8.

I don't mean to hijack this thread, but could someone who knows tell me if I need to get spraying or not and if I should cull and burn this plant - as I noticed this just now:



Our local GC does not sell Dithane, they said it has been withdrawn? They do have Bordeaux, but, I read that this persists longer in the soil?

Thanks

[marchogaeth]

I'm prepared to be wrong but I don't think that's blight. If you are worried just pull of and burn the individual leaves. Get rid of any dying leaves in the bottom of the rows.

[Tripmeup]

Doesn't look like blight to me either...