[GardenShed]

Hi, I planted my maincrop potatoes in March and the plants had come on quite well, but in last few days are starting to go yellow and some are falling over.  Is there something wrong with them, could it be lack of water, I've not been watering them much.  If the latter, can they be fixed?

Is it possible they might be ready? No flowers yet though.

[DD.]

Could be another case of blackleg.

If you do a forum search on it, you'l find quite a few threads.

[JayG]

Pull on one of the wilting stems and if it comes out very easily, and has a blackened, rotting end, that is a pretty good sign of blackleg.

If not, dig up one of the affected plants and examine the roots and tubers carefully - if you can see lots of tiny white, yellow, or brownish egg-like structures (smaller than a pin-head) you have an eelworm problem (PCN.)

In both cases any tubers are OK to eat if they look sound, but you should dig up all affected plants and bin the haulms to reduce the spread of the disease, although PCN in particular is very difficult to get rid of as it is can live for many years in the soil even in the absence of its host.

Hopefully yours are just dried out - they need to be kept watered as the tubers start to swell, especially in very light, dry, soils.

[GardenShed]

Thanks for the advice, I tried to pull one out tonight and it did not come out and I cannot see any black on the stems so I don't think it is blackleg.  Ive not yet pulled one so have not checked for the eelworm - will do that tomorrow. 

They did not look as bad today as I thought, not all of them are falling over, so I wonder if it is simply that they were really dry.  I gave them a good watering yesterday and today, so perhaps they will fix themselves.  No flowers yet though.  Do potatoes always get flowers?

Lastly, given that they are maincrop and were panted in March, when would they be ready?

Thanks a lot.

[solway cropper]

Not all potato varieties flower so the best way to know if there's anything there is to have a feel under the soil/compost. I'd normally give maincrop 20 weeks+ but just leave them unless they show any sign of blight.

[GardenShed]

OK great, Ill check them tomorrow.  Sounds like they will be ready in August / September.

[Fairy Plotmother]

I think I need to follow this advice....thanks. Does it make a difference to any diagnosis to say that the flowers have died. Should I just dig one up to look!