Potato Blight.

wayland · Potato Blight.

Not had much experience with potato blight but two of my plants have keeled over. I thought the first signs was black blotches on the leaves but these plants just folded up their leaves and died. Any ideas as to what this problem might be and what to do about it please.

quarryman

If they have flowered you can lift them. If not, cut the foliage back and leave them for another while. They should be fine.

If you do notice the start of blight, cut and remove the foliage and the tubers will continue to mature.

wayland

Thanks for that quarryman. The earlies seem ok and I dont want to lift the maincrop yet but better that than loose the whole lot.

Cheers.

admin

Here is an extract from an earlier thread on this topic . Basically there are 2 types of blight -- Early and Late . You can distinguish them by visual inspection . The Early form will knock back the tops but not harm the spuds beneath . It is the Late type which does all the damage .
HTH Wink

This one is specifically about the Early strain , c/w pictures http://plant-disease.ippc.orst.edu/disease.cfm?RecordID=886
This one covers both Early and Late
http://www.hort.uconn.edu/ipm/veg/htms/bltpot.htm

wayland

Just an update. I lost me bottle and cut of all the tops. I did spray them with copper stuff but the blight was everywhere. Perhaps it would be better to spray by season than by the first signs of blight. We never got blight in the dry fens so there is clearly a lesson to be learnt here. I lifted a few of the main crop tubers and they look fine. Its a pity that what looked to be an exceptional crop had to be cut short . Ho Hum Crying or Very sad

How do you organic guys deel with blight?

squirrel01

buy from tescos Laughing

keithrawlins

i cut of the tops if there is any blight and leave the tubers till the time they are due to lift they seem to grow onfor a bit without the tops

trufflehound

We had blight last year & as some have already suggested, we cut off the tops & left the potatoes in until we were ready to lift them. Majority were fine, although a lot had very small dots of soft creamy white on their surfaces - I presume this is the first stage of blight in the tuber?

Anyway it rubbed off - & certainly washed off - fine.

This year we didn't plant any spuds but still have plenty growing - presumably from the little ones left in from last year. They were quite late in coming up but have started to dig them in the past week & they are lovely!

quarryman

Well the blight struck. So I cut the foliage of all the plants. We only dug up a few spuds and they are fine.
You really do need to keep on top of things or you could loose the lot.

wayland

Interisting tips guys. Thanks Very Happy

. I am now loosing sleep over my outside toms. Come to think of it , the inside ones as well Confused

Graney

I notice they have a blight warning service on Met Eireann. It has been predicting blight conditions this week.

I put on a couple of sprays earlier, but I've been a bit reluctant to do it in recent weeks as we have a growing puppy with a penchant for licking leaves ... well anything actually .... but I could imagine him finding the potato leaves particularly tasty with a blight spray on them.

Seem to have got away with it so far ... no signs of blight yet.

greentree

I have never had blight here and have grown at this spot for 8 years. I think its something to do with my elevation - 820ft.

trufflehound

We are at 960ft & get blight every year! This week has been warm & misty - perfect blight weather, so expect all our potatoes to keel over in next week or two.

wayland

I hope they dont and am surprised that you get the blight at your altitude. I have always been under the impression that over 1000 ft you dont get it. Your only 60 ft short of this. Good luck.

trufflehound

Leaves are turning yellow & spotty as we speak.. Crying or Very sad

But just dug up some of the spuds & they are fine Smile

wayland

Sounds like blight Crying or Very sad

Are you going to remove all the tops? My outside Toms have it now. Crying or Very sad

Aint nature wonderful Smile

trufflehound

Am cutting off the tops once they seem to be affected. Did this last couple of years & most of the spuds seem to last reasonably well for a few weeks at least.

Only have toms in greenhouse, so they seem OK.

My (one & only) aubergine plant is covered in aphids, though!

MrsL

Nothing here, lucky to only have had a bit in 20 years. Hope that's not famous last words............

Graney

blowin

Spraying certainly helps if you do it at the appropriate times . I don't think there is much of an alternative when it comes to blight . Does anyone know of one ?
I call it " pragmatically organic " . You can have a reasonable crop of almost-organic veg , or no veg but a lot of totally organic weeds . Not really desireable but at least you know exactly what has been applied and in what quantity .

Graney

That's exactly my view Blowin.

I tend to use a few slug pellets to prevent total loss of young plants overnight - which can happen. Use them carefully and they should cause no problems to wildlife and no chemicals are absorbed by the crop plants.

And I use blight sprays - only when necessary and again to avoid 100% crop loss. That's what happened last year when I wasn't around to spray when it was needed.

Other than that I use nothing apart from fingers to pick off caterpillars and a good mix of crops to encourage natural enemies of the pests. And I have a degree of tolerance to holes, nibbles and a bit of rot here and there.

In the end the veg I produce has got to be a lot healthier than from the supermarket, but I haven't had to wear a hair shirt to produce it.

wayland

The blight has got to some of the tubers and what a stinking mass they are. So next year I will spray Sad

. I guess I should not plant next years crop near this years spud bed which I would not do anyway, but is one year long enough to clear the spores from the bed> I am told that the Min of ag or some such boddies gives out blight warnings. Can any of you guys tell me where I might get such warnings?

Cheers.

quarryman

The weather forecast on the Irish news will give Blight warnings. The Met service will also do this www.met.ie

wayland

Cheers for that Quarryman. Very Happy

blowin

A lot of ours have suddenly gone mushy too . Sad

The King Edwards went some time before the Desiree . Don't know why .

What is the logic behind leaving them in the ground for a couple of weeks after the infected stalks have been cut off ? Would it not be better to dig , wash and dry the spuds as soon as you see blight up on the leaves ?