Potato Problems

[Killmark]

Hi,

This is my first time growing potatoes I was wondering if people might be able to identify whats happening with my potato plants. I recently went on a short holiday and everything was green and a couple of my earlies were in flower but when I returned I found one of those plants had collasped and died. I couldn't be sure what had happened as it could have been trampled by a fox or something. So I have been keeping a close watch in the meantime.

When I went yesterday I found two other plants looked like they were shriveling and dying at different sections of my row.



Any diagnosis?

[Martin H]

It looks to me like the result of some physical damage. When this happens on my plot it's usually slugs having munched the stem below the ground...

Whatever it is, this plant isn't going to do any more growing, so I would dig it up carefully and see if I can spot what the problem is.

[teakdesk]

You say a couple of your earlies flowered and one of those then died?

I wouldn't expect earlies to flower as they get dug up and harvested before they are old enough to flower so either they are ready or they flowered early because they were already stressed and dieing. How long ago did you plant them?

[Penellype]

Its not possible to see the stems in your photo. Do they look green or black and mushy? Yellowing leaves and curled foliage are signs of blackleg, but the definitive symptom is a blackened and rotting stem - the potatoes also rot. If there is any sign of blackening or rotting you would be best to remove and dispose of the affected plants - don't compost them. Clear up as much of the debris as possible as the disease can overwinter on bits of potato plants.

Even if the stems are not black, the plants are clearly not happy and I would be inclined to remove them and get rid. You may or may not be able to eat any of the potatoes.

[Killmark]

You say a couple of your earlies flowered and one of those then died?

I wouldn't expect earlies to flower as they get dug up and harvested before they are old enough to flower so either they are ready or they flowered early because they were already stressed and dieing. How long ago did you plant them?

I planted these in the last week of February. Main crop have just flowered. The 1st early that died I dug up had a large solitary potato.

I have a couple of plants in pots (planted in first week of March) and had a look at to see if any tubers had developed. The earlies had small tubers about the size of a 10p coin, didn't want to dig around too much though.

I checked the stems on the dying plants today and no black marks on, same for the leaves, but they had curled up and were going yellow.

[poly]

If they are not naturally dying back due to having produced their crop then I agree the plant doesn't look happy at all and best removed. Have to agree it looks like Blackleg to me as well and would remove it and any others that show similar signs as per Penellype's advice. Sometimes it takes a little while for the stems to look blackened at the surface, sometimes they can look like they have a white film before they blacken.

[teakdesk]

I planted these in the last week of February. Main crop have just flowered. The 1st early that died I dug up had a large solitary potato.

I have a couple of plants in pots (planted in first week of March) and had a look at to see if any tubers had developed. The earlies had small tubers about the size of a 10p coin, didn't want to dig around too much though.

I checked the stems on the dying plants today and no black marks on, same for the leaves, but they had curled up and were going yellow.

Main crop often flower and some second earlies will too - some of my second earlies are starting to show signs of flowering but I know they are stressed being planted in an old lawn with little depth of soil as a stop gap to work the land next season.

To me, earlies will crop in as little as 7 weeks up to 10 weeks, second earlies take 12 to 14 weeks and main crop around 18 to 20 weeks.

You don't say where you are but I'd not plant earlies out until end of March and crop them end of May and through June. Earlies, in my experience, produce a few tubers of excellent taste rather than a large harvest. They do need warmth and a rich soil to achieve even this though.

[jonny the plant pot]

A lot of my earlies are in flower should I start to dig them up when my leg is better.