Potato blight

[Victoria]

How disappointing, went to allotment this morning to pick the rest of the broad beans, and my potatoes are showing signs of blight. They haven't even flowered yet. Anyway, have cut off affected stems and leaves and taken away. Will have to keep a close eye.

[Geoff]

Are you sure?

Blightwatch don't seem to think so http://www.blightwatch.co.uk/content/bw-Home.asp

[oldherbaceous]

Dear Victoria, it certainly does seem rather early for blight!

[Westi]

Hi All

Just mentioned today if we didn't know better we
would have thought our Int Kidney had blight but
it is only them and all the others are right as rain,
but if they had been stand alone they would be
gone.
Don't know what it is but they are weak and pathetic
and miles behind all the other spuds so probably something
in the soil in that spot or a naff bunch.
Here's hoping you haven't binned them for nothing!

Westi

[glallotments]

Could it be scorch? Sun on wet leaves etc?
AI overheard someone saying his tomatoes had blight but I thought the same as others - it's too early for that surely.

[Victoria]

Well I hadn't thought of sun scorch, I haven't thrown any potatoes away and only the tops of one so no loss incurred.

[macmac]

Several of the plotholders on our site have had problems with potatoes this year.Some look poor with a poor yield,some look ok one minute and collapse the next one guy had that happen and despite very healthy looking original growth there was nothing underneath .Another guy had odd plants collapse but the potatoes underneath were fine We've had mixed results International kidney were good Sharpes express poor,but the best by far were Yukon gold.

[Monika]

One of our allotment neighbours has had problems with curly leaves on potatoes, probably a tuber-borne virus disease (I don't know the variety of the potato). The plants look as if they have been affected by weedkiller: thin, straplike leaves which are curled up. We were worried at first about the cow manure (see gallotment's splendid campaign!) but other varieties grown in the same bed are perfectly ok.

Anybody else had problems like that?

[oldherbaceous]

Dear Monika, i think there were 2 other topics in this setion that were describing similar signs.

[FelixLeiter]

It's natural to attribute iffy goings-on with your spuds to blight. It's always the ailment we dread the most of our crop, so it makes us jumpy. But often minor calamities with potatoes' health are down to something else entirely. Often, it can be that foliage on tatties dies down quite naturally to indicate that the crop has matured. First earlies should at this time of the year be starting to do that. They go yellow, usually, followed by brown spotting and then quickly shrivel. I've seen gardeners get very upset to see the leaves on their crops wither, only to be delighted to see that there's in fact an excellent crop of tubers when they dig around. But there's also the ubiquitous blackleg, which it is rare for a potato bed to escape entirely from in most seasons: there are nearly always one or two in a plot that get it and the results can be rather final, but only for the affected plants. There are very many diseases and beasts that ail potatoes and actually, in a good season (such as this one so far), usually the least of these worries is blight.

[Victoria]

Well, my potato plant had collapsed, brown spots, yellowish leaves - I guess I just panicked! No flowers on my spuds at all so far, eveyone else on the site has loads, perhaps its the variety I've planted, whose name I have forgotten - doh!

[oldherbaceous]

Dear Victoria, all my earlies are dug before any flowers are open.

[glallotments]

One of our allotment neighbours has had problems with curly leaves on potatoes, probably a tuber-borne virus disease (I don't know the variety of the potato). The plants look as if they have been affected by weedkiller: thin, straplike leaves which are curled up. We were worried at first about the cow manure (see gallotment's splendid campaign!) but other varieties grown in the same bed are perfectly ok.

Anybody else had problems like that?

Monika
Can I ask if the variety affected was Picasso?

We have someone on our site with potatoes that have symptoms of herbicide contamination even though he hasn't used anything on his land. The RHS say that the symptoms are consistent with herbicide poisoning. They also said potatoes that are stored or chitted where herbicide is stored could absorb vapours! Has you plot neighbour stored any hormonal lawn weedkiller in his shed with his potatoes We are wondering whether it is possible that seed potatoes can become contaminated prior to buying.

[Compo]

The key here is that those of you that are complaining of potato failure are not seeing neighbouring plots 'infected' blight will spread down a plot like a forest fire (albeit slightly slower) it is very usual to have pocket infections that do not spread slowly down the field where there are several plots.

Also the lack of a full smith period (for technical explanation see the links on previous postings http://www.blightwatch.co.uk/content/bw-Home.asp)

this basically means a prolonged period of high humidity and a moderate temperature which are the ideal breeding grounds for spreading the blight spore.

So I think that there are as others have said 'other' reasons for these potato crop failures. Last year I signed up for free to blight watch which was a way of receiving text messages about blight near you, and the mobile was bleeping two to three times a week. This year I have had no blight alert messages

CoMpO

[Monika]

glalllotment, the allotment neighbour with the distorted potato leaves seems to have gone on holiday - I can't contact him, but I do know that not so long ago he sprayed weedkiller all round the perimeter of his allotment to stop the long, surrounding grass from creeping in, so I wonder if that caused the problem? I will also find out which variety it is that is affected.