Blight watch 2017

[cariann88]

I got a email warning this morning saying we are in the red here. I think I am going to keep my outdoor toms inside the greenhouse a bit longer until it clears. My spud I put in the ground ages ago have not even produce leafs :/

[veggiechicken]

In the red again today

[Penellype]

Same here, although I haven't yet had an email alert.

[Nicos]

Not aware if we have a French version of this, but it wouldn't surprise me if we were in the red zone today....warm and very humid....and our spuds are not even up yet!

[seasprout]

I've received a blight warning for LE3.

Not a happy bunny.!

[veggiechicken]

Don't know anything about this stuff, but...................JBA Blight Guard - Hessian sacks & Sundries

[cariann88]

I am going to buy some Epsom salt and see if that works

[lmayhow]

So with a red day in my postcode but pouring rain is it worth putting Epsom salts down when the rain has stopped even if the 'red' stage has passed? Just earthed up my potatoes this morning at the allotment and have been hardening tomatoes outside for a week now again its raining :eek

[Jonnyt]

Late blight in May? Someones having a laugh.

I doubt the spores have even woken up yet.

[seasprout]

Late blight in May? Someones having a laugh.

I doubt the spores have even woken up yet.

Unfortunately there is such a thing as early blight.

I've had another alert today.

[veggiechicken]

After 2 days in the red, I'm back in the green Hope the spuds have survived

[Greenleaves]

Full Hutton here today, but not to worried at moment

[Penellype]

Got an email today but back in the green for tomorrow, when it will be much less wet and also cooler over night.

Red does not mean you will get blight, just that the conditions for it are favourable. Blight takes about a week to show, and the worst conditions are for smith (hutton) periods a week or so apart. Don't panic though - htere were 3 or 4 smith periods last year before my potatoes finally got blight.

Whether Epsom salts will help at this stage I don't know. It can't do much harm to apply it to already wet leaves once the rain stops.

[Penellype]

With the warm and humid conditions returning, blight alerts will be starting to arrive if they haven't already. Blightwatch have updated their page about Hutton periods and explained why they have done this and what is different from Smith periods - they are not quite the same - the old Smith period required 2 consecutive days with 11 hours of 90% humidity - this has been cut to 6.

Now: The Hutton Criteria

Two consecutive days:

Each day has a minimum temperature of 10°C
Each day has at least six hours with relative humidity ≥ 90%
Performance up from 41 to 69 % of > 2000 historic potato late blight outbreaks receiving an alert
Increased proportion of days receiving an alert from 7 to 16% for a 28% gain in performance
Improved consistency in alert performance across all regions of Great Britain
The future for Blight modelling and alert systems.