Aaarrgghh! tell me its not blight!!!

[Protea]

Went out to peruse my potatoes in bags this morning - only to discover little brown spots all over the leaves

My first thought was blight - but its very 'dotty' unlike splodges of blight. The mature potato plants have it badly and some of the younger ones are showing signs.

I'm on standby with the Dithane if its confirmed. Pictures attached - am i doomed?

Some of my tomatoes which are yet to be planted out, are also looking a bit dodgy - but it looks different to the tatties, and could just be nutrient deficiency from still being in tiny pots.

Cheers for any help

[Cutecumber]

It's not blight - I promise. I have it too, I've had it before. I get it on both tomatoes and potatoes.

I am sure it is a nutrient issue. It has never killed anything yet!

[Protea]

Cheers CC, Phew!

It also looks a bit like chocolate spot on beans, but i'm sure its not the same thing!
Wierd as those tatties had loads of fertilizer (probably too much - i've ended up with to much top growth!).

Going to do a preventative spray with Dithane since the weather has been so wet, and give a general purpose liquid feed.

Fingers crossed.

[Earthbabe]

I've got it this year too and I'm convinced it isn't blight as I've had that as well (well my spuds have!) in the past. Not sure what it is. On some of the "affected" plants it is also combined with the leaves starting to yellow so I don't know if it is to do with harvesting.

[Alice]

It's not blight Protea. I've just emptied a bucket of potatoes. The leaves were all like that. We don't have blight in Scotland. The potatoes (Charlotte) are just beautiful.

[Alice]

I saw that too L J. But the description of magnesium deficiency they give matches with it as we would understand it, but the picture doesn't match the description at all. Could they have got the wrong pic ? We all make mistakes.
Maybe a Grape with time to spare could ask them.

[noidea]

I have this too at the moment but on a pepper plant. It seems healthy enough and hasn't spread to anything else that is in close proximity.

C

[Protea]

OK - have checked my notes and Mg deficiency occurs as interveinal chlorosis on older leaves - its definately not that, there's no interveinal chlorosis, and the spots are occurring on new and old leaves.

I'm actually a member of the RHS - i think i may send a leaf sample off to them to get tested - i'll let you know what they come back with!

However - i think i have 'over-potashed' my tomatoes - whoops! need to get hold of some magnesium foliar feed.
Cheers all - at least its not life threatening

[Protea]

Just found this on Cutecumber's reply to another thread: http://aggie-horticulture.tamu.edu/t...leaves/5c.html

looks more like bacterial speck - and the symptoms and cause seeems to fit - lots of leaf wetness lately!! It suggests a copper spray, which i have.

[Earthbabe]

Thanks Protea. It does indeed look like that. Will definitely ask Mr EB to tackle his sprayer over the weekend.

[heebiejeebie]

noticed today that some of my tatties have the same symptoms!

[spudman]

I noticed the same brown spotting on some of my spuds today, and on one of the plants the leaves have virtually all gone yellow, is this something to be concerned about ? I've looked at some of the other allotments and all their spuds seem fine,it just seems to be mine. Any words of wisdom much appreciated.

[mikk100]

oh dear, i noticed this same thing on my new pots. yesterday and on a few leaves of my old potatoes...(only a few rows apart) I remembered what I'd read in GYO magazine on friday and promptly chopped all the foliage off my new potatoes for burning. I haven't yet massacred the main crop and am very pleased now I've found that it itsn't blight after all...phew...but should I dig up my new pots. now that they have no leaves?

[Earthbabe]

Mr EB very kindly got the sprayer out yesterday so I'll report back when I can see if it has made a difference. He also got the weedkiller sprayer out for the roadway by the plot and sundry other areas on the lottie. Says he enjoys doing it - bless!

[Cutecumber]

I can promise you that, whatever this is, it will not hurt your crop. You do not need to use any pest or disease control - a feed would not hurt, however.

I have had it every year on some of my potatoes and it has not escalated into anything worse, nor affected the yield.

Panic not.

It ain't blight.