Kitchen Garden Forum

The leaves on some of my potatoes (Arun Pilot & Desiree) are going yellow. Is this blight? I don't want to dig them up if they are still OK. I did spray with Bordeaux Mixture a month ago, but it may have been washed off by the rain. Thanks for any advice.

I thought leaves (both potato and tomato) went black with blight rather than yellow so wonder if itss lack of nutrients. Have only grown potato's in containers so am sorry I'm not an expert. Hope somebody comes up with an answer for you.

Hi JohnN,

Blight appears as dark brown/black roundish spots on the leaves & then streaks on the stems & then it goes to mush. You will generally find it on the leaves first. I am anticipating I will get an attack this year with this rain & warmth cycle we are having so have some copper spray on hand, but it just delays the inevitable so you can at least harvest & save your crop.

You can sign up to Blightwatch for free & they will send you an alert if the weather conditions are right for blight in your area so you get a chance to spray at the right time.

I’ve had around 5 earlies go yellow ish then die I put it down to lack of water although I’ve watered a few times there’s that much looking for water as it’s been bone dry all June and most of may I dug one up that had died but it was like digging concrete,our council won’t allow sprinklers and frown on hose pipes they expect us to use watering cans ,it’s raining at present with a promise of moore to come

Thanks all for your comments. I dug up one of the yellowing Arun Pilots and the crop was fine - a reasonable yield of medium and small "earlies", some of which are going to grace today's lunch table of fresh grilled salmon!

Our site in Warwickshire has been hit by blight this week. I've topped the potatoes and am praying for the heritage tomatoes which are both outside and in our polytunnel. So far they're OK, but my plot neighbours have lost theirs, including one lot in a polytunnel.

The blight proof tomatoes are fine, so we we will have plenty, but the heritage taste so much better and come in so many shapes, sizes and colours, I do prefer them.

I wouldn,t be surprised to get another blight warning any time now. Just what we need now the fruits are starting to appear on the plants!

I'm registered with Blight Watch and haven't had a warning this year. Just got blight.

When I first had an allotment 20 years ago, we went 5 years with no blight and have had it every year since. Is it getting worse or were we just lucky for a while? The old timers on our site swear it was never a problem until recent years, but the past always looks more rosy

That's bad luck Chantal. I never know what to use for it these days that,s easily available . Most or the previous sprays I previously used like Dilthane seem to have been withdrawn or are no longer available .

I used to use Bordeaux Mixture but gave that up (is it still available?) when blight proof tomatoes became available. My polytunnel is unscathed as yet, but one bed of heritage is fighting the odd leaf spot. I'm removing leaves as soon as I see damage, but I fear that all is already lost. It would take a miracle to avoid this. All around me are stricken.

However, I'm luckier than most with around 40 Crimson Crush, Blush, Plum and Cherry that will make it.

I timed a copper spray just right as got no warning but just knew, so saved the 2nd earlies & main crop except for the odd leaf which is off. Toms are in the tunnel & they had a spray as well as although I have blight resistant toms in the mix it couldn't hurt as they are only meant to be resistant & this year they will need to be! Nothing from Blightwatch either so checked the site to ensure still registered - after changing password as couldn't get on the site it showed a calendar to check & that wouldn't work. Hmm? It was so reliable before!

Well got caught out despite my best efforts & have blight as well. It rained down there on Friday night which was not forecast & I did not get any at home, but definitely blight insitu & just moving into the stems. I was not going to go down but the winter brassica plants were not enjoying their pots & looking a bit stressed so decided I would just go down & plant & net them as way too hot to do much. Mind just planting & netting them took 3 hrs but I would say at least a third of that time was chatting to the neighbours & passer by's as you do!