Christmas potatoes foliage up and blight risk

[Marb67]

I have my Wilja Christmas spuds planted in large bags and pots. The foliage is coming through nice and strong. The question is, is there now a danger they can get blight or not? I can't add any more compost to the pots as they are already full but I can cover them in the bags as they are deeper.

[Jungle Jane]

Are your potatoes near to any tomato plants that are showing signs of blight,there’s a risk if so. If there’s no blight I don’t think you need to worry,the weather is warmer than usual at the moment,I would keep an eye on the nightshade family out there checking for signs of blight. I haven’t seen blight here yet this year,hope you don’t see it too I personally wouldn’t cover them I’d worry about lack of air,overheating & the moisture causing condensation on the leaves,I only cover the bags with a row cover,if a frost is forecast,leaves blacken when it’s frosty.

[Marb67]

Its the warm weather that blight is more at risk but its gone much cooler up in Cheshire now. There are some small toms at the end of the plot about 25 feet away that were put in too late that probably won't fruit but I have cut a few leaves off that were showing mild signs of blight here and there. But then again, can't potatoes get blight without the aid of toms ?

[ameno]

Blight spores can blow in from a fair distance away, like another garden or allotment, or even a farmer's field a few miles away. But obviously having a source of spores relatively close is only going to increase the risk of infection, so potatoes or tomatoes grown near other potatoes or tomatoes, especially ones which are already infected, which be at much higher risk than those grown in relative isolation.

[Marb67]

I'll just cover them all with soil till the threat of blight is over in October.

[ameno]

Not a good idea. For starters, the threat of blight won't be over until at least late October, probably later if we get a mild autumn. And secondly, the plants need those leaves in order to grow, especially while it's still reasonably warm. You can't just keep them covered for over a month and only let them grow once the days are short and the weather colder. You'll never get a crop that way.

[Marb67]

Not a good idea. For starters, the threat of blight won't be over until at least late October, probably later if we get a mild autumn. And secondly, the plants need those leaves in order to grow, especially while it's still reasonably warm. You can't just keep them covered for over a month and only let them grow once the days are short and the weather colder. You'll never get a crop that way.

Well now they have blight. The ones in larger bags don't seem as bad. I have cut off the infected leaves. I should have gone with my instinct and covered them over. I just can't win can I

[smallblueplanet]

Well now they have blight. The ones in larger bags don't seem as bad. I have cut off the infected leaves. I should have gone with my instinct and covered them over. I just can't win can I

You were warned. Why not go with nature?

[Marb67]

You were warned. Why not go with nature?

Warned ? I didn't cover them like advised. I knew this would happen even before I planted them. The slim chances of blight but I knew it would have to be me. Expect the worst and you won't be dissapointed is my motto.

[ameno]

Well now they have blight. The ones in larger bags don't seem as bad. I have cut off the infected leaves. I should have gone with my instinct and covered them over. I just can't win can I

You wouldn't have been able to cover that with more soil, anyway. The pot is already full.
But even if you had been able to cover it with soil, yes, it might not have gotten blight, but it also wouldn't have been able to photosynthesise. The plant would have been very weak by the time you allowed it to actually see daylight, and by that point the temperatures would be too low for it to grow fast enough to catch up. You'd still have gotten no actual crop, even if the plant had might have remained disease free.

At this point, I would suggest removing only the infected leaflets and leaving the rest, and keep doing this, to try and prolong the life of the plant as long as possible. If it spreads slow enough you might still get a small crop of little potatoes. Better than nothing, at least.

To be honest, growing new potatoes for Christmas outside has already seemed like a foolish idea to me. Potatoes and tomatoes get blight pretty much immediately this time of year. I can't imagine it would work anyway in this country.
If you want Christmas new potatoes, the pots really need keeping in a greenhouse or polytunnel (and one without tomatoes in it, at that, as they are a potential source of infection).

[Marb67]

Foolish idea? Gardener Sean James Cameron grows his outside in the ground. They were the only hope I had on this plot thus season after the sprouts being still in pots. as I was going to overwinter them in the pollytunneel before the cold set in. The ones in the pots were going to be transplanted into larger bags when the roots got going. They are not new anyway, they are Wilja, a roasting spud. .

[ameno]

If he grows them successfully outdoors then he must, by some miraculous coincidence, live in a relatively blight-free part of the UK. Perhaps he has no farmed fields anywhere near him, as potato tips on farms are the most common innitial source of blight spores each year, and it then gradually spreads across people's gardens and allotments.
In most of the UK, blight is an inevitability in outdoor crops. To be honest, him recommending people grow late summer potatoes outdoors seems pretty irresponsible, as he is setting most people up for failure.

Although if you were trying to grow roasting potatoes using this method then that was doomed from the start, anyway. This late planting "potatoes for Christmas" method is to get new potatoes for Christmas. It won't work with roasting potatoes because maincrop need much longer to grow.
Also, there's no need to grow maincrop potatoes in time for Christmas because they keep well. Just grow them at the normal time, harvest them in September, and store them in the shed until you need them. They should keep until next Spring.

[Marb67]

The Wilja variety is marketed as a potato for Christmas but I will take on board what you say. The plot is bang in the middle of farming countryside, very remote.

[smallblueplanet]

Warned ? I didn't cover them like advised. I knew this would happen even before I planted them. The slim chances of blight but I knew it would have to be me. Expect the worst and you won't be dissapointed is my motto.

...Foolish idea? Gardener Sean James Cameron grows his outside in the ground.

It's nothing to do with expecting the worst and a lot to do with your ability as a gardener. When I first started growing I accepted there were many things I did not know nor understand the affect of and tried to grow following 'best practice'. If things failed I would think to myself 'well that could only be expected, trying to grow aubergines outside in Derbyshire'. I then did everything I could to provide the plants I grew with the conditions they needed, not the conditions I wanted them to have. As I have gained more knowledge I know that boundaries can be pushed but still I realise there will be a payback in health or vigorous nature of the plant(s) being grown. I do not blame uncontrollable conditions and say 'expect the worst'.

When you have the experience and ability of Sean James Cameron perhaps you too will be able to grow in a similar manner? You realise you lack knowledge yet when you are given advice you mostly chose to continue along your own path. Your potatoes have blight and you don't seem surprised just disappointed. What does that tell you?

Edit: Mea culpe for the schadenfreude, but you cannot expect to ignore the needs of the plant just because you haven't enough space or the correct conditions. Sorry.

[Penellype]

There is no harm in experimenting or trying to push the boundaries (particularly in the currently rapidly changing climate) as long as you realize that many such experiments will fail. It may not be because it is a bad idea, you may simply be unlucky (or lucky). I have tried to grow Christmas new potatoes on 4 separate occasions, using Charlotte, marketed for the purpose. The first year I tried it I got a reasonable yield from 2 buckets, and decided this was something I could do. The following 3 years all resulted in a total loss from blight and I realized that the first year I had simply been lucky.

This year is a very bad one for blight. The weather has been warm and damp for some time, which are ideal conditions for blight to thrive and spread. For the first time ever some of my main crop Desiree potatoes got it, and I removed most of my tomatoes yesterday as they were showing unmistakeable signs of blight after a couple of earlier scares (I cut off the affected parts immediately, which seemed to help). Some years I have got through to the end of October without blight, usually it strikes around the beginning of October.