Topic: What is happening to my potatoes?

[Gordonmull]

Wondering if anyone can shed any light on why a few of my potato plants are withering?

One started about a month ago and has died off, I just put that down to one of those things. Then I noticed about two weeks ago another four had started to curl their leaves. Later they started to become a bit wilty. No signs of lesions or any other marks on the foliage. I had a good grub down into the soil around the stems and those are free from damage or any marks that would indicate disease. Soil is acid clay and it is definitely not drought.

Photos are here, note the second picture where the plant has three unhealthy shoots to the top and the right, while the shoot on the left seems OK.

http://www.flickr.com/photos/57278801@N04/sets/72157634458512877/

[Jayb]

I'd suspect Blackleg, there seems to be quite a bit of it about this year    I've pulled and destroyed a few plants, all grown from bought in seed potatoes
http://apps.rhs.org.uk/advicesearch/Profile.aspx?pid=223

[Digeroo]

What about ants? 

[Pescador]

Photos don't seems to show any stem infection, so I'm not sure about Blackleg.

[Jayb]

Hopefully it won't be Blackleg. But I noticed with one or more of mine, same wilty leaf with no sign of it on the above ground stem, but when I pulled the haulms they came up easily with blackened stems beneath.

[Ellen K]

Hopefully it won't be Blackleg. But I noticed with one or more of mine, same wilty leaf with no sign of it on the above ground stem, but when I pulled the haulms they came up easily with blackened stems beneath.

^^ Exact description of some of my potatoes, tubers were rotten too.

:-(

[Gordonmull]

Nothing seems rotten below ground. blackleg was the first thing i thought of, so I checked the stems. They all seem healthy enough, in that respect, anyway. I saw it last year in some plants, so I know what it looks like and it doesn't appear to be that. No signs of physical damage, no obvious disease marks. 

[davyw1]

I think it may be worth having a closer look and see if any thing like voles have been traveling under them

[Gordonmull]

Right, I'll get in with the fork on one of them and see what I find. Cheers, Davy.

If there's been voles at them then the cats are getting the sack lol.

[davyw1]

Right, I'll get in with the fork on one of them and see what I find. Cheers, Davy.

If there's been voles at them then the cats are getting the sack lol.

Put the taties in the sack and the cats in the hole

[Gordonmull]

Put the taties in the sack and the cats in the hole

Sometimes that's a tempting thought Davy but as long as my soft fruit stays unpecked by the starlings and pigeons then they get to stay above ground!

The stems are rotted deep down, root system is a goner. Some healthy spuds came up but one rotted one. I've put a couple of pics up. This is now affecting 7 of my plants.

http://www.flickr.com/photos/57278801@N04/sets/72157634521298069/

What's the best approach here? Pull up and burn? Should I lift the spuds under the plant as well?

[davyw1]

The leaf to the left of the spud cut in half is blighted and i would say the same for your spuds

[Gordonmull]

Rats! I never even considered blight. Certainly didn't notice that leaf. It's been so dry here this year that blight has disappeared off my radar.

I've removed the haulms from the affected plants and destroyed them. Here's hoping for no more troubles.

Thanks for the advice.

[telboy]

Gordonmull,
There is something confusing me about your problem. I have no experience of blackleg so can't comment. Blight, however, I have.
You may experience odd leaf wilt but when blight hits it's devasting, the whole crop will go down in 2 days. The state of the spud is awful, I can't understand how the spud can rot like that with other plants still standing. Very strange.

[Gordonmull]

Could be one or two of the seed pots were carrying it over from last year, although they were bought seeds, not saved or supermarket ones. It's definitely not "blown in" because, as you say, it wouldn't be a few plants I'd have been cutting down, it would be the lot.

It's not even just that, but there were other, healthy, spuds from the same plant. 

A bit more history on this bed - I converted it from lawn last year and it had all my veg except spuds grown on it. Carrots, onions, leeks, various brassica, beetroot. This is the first year of spuds, so I can't see it being some sort of soil-borne issue.