Potato Blight in polytunnel

Hello All

Each year I grow 10 pots of early potatoes in my polytunnel, moving them out before the tomatoes go in to reduce "blight" problems.  I planted the bought in (from a different supplier this year) seed potaotes chitted as usual, though a bit later than normal because of  the cold year.

They are in good large pots filled with home made compost (I don't put any blighted haulm into the compost heap) with a good couple of handfuls of seaweed meal.  They have looked a bit wan, so I fed them with some very expensive organic feed a week or two ago, and have covered them with fleece if frosts were forcast.

They still look dire, and today looking them over I think they have got blight.  Does anyone know what could cause this so early?

 I did have blight on the tomatoes last year, but removed all the affected leaves as they came, and put them in the dustbin, and the plants were removed as soon as the tomatoes were havested and they and the compost were put on a burning pile.

I fill the pots half full and top them up once as the haulms grow, so the pots are now full but the haulms are a very weedy looking 6to 8 inches.  Frail, and yellowish green with a few yellowish brown patches on the leaves.

Many thanks for any advice
Susan

PS As I am growing for my own use I prefer to avoid anything too "un-natural"

Most probably frost damage

Hello Susan.  Could you put your location in your profile so we can have an idea of the weather conditions in your area. 

I also say its frost damage.

I think a lot of folk would be very happy to have spuds looking as "dire" as yours!

My bet would be that they have suffered just a touch of frost to a few leaves; most of them look fine to me!

Quite.

Just for reference, there are no incidents of blight reported yet.

All you need to know is here:

http://chat.allotment-garden.org/index.php?topic=56717.0

Hi All and many thanks for the input.

I feel a little happier now - I suppose I had such a "blightly" year last year I was panicking.  Out of interest the last 2 photos on this

http://picasaweb.google.co.uk/marose1234/PotatoPlants#

are self sets which have popped up in the same polytunnel. 

What does everyone think about leaving self-sets to come.  The received wisdom seems to be that self-set carry blight, but they always seem to do better and come so much sooner than  planted seed potatoes.  I feel guilty about them and sometimes root them out and other times my "thrifty" side says leave them and havest some early potatoes.

Many thanks for the replies
Susan

As JayG says - your call, but you can bet your bottom dollar that the first cases of reported blight this year will be in "outgrade piles" (not good enough for market), or "volunteer" spuds. I've never seen the first report in a fresh planted crop.