Potato blight

[David]

Our neighbours have been struck badly by potato blight.  Their whole crop has wilted foliage and they have now cut off all the foliage, and are waiting to inspect the potatoes.

We have planted Rosabelle and Belle de Fontenay, and now one of them is showing signs of blight on about 10% of leaves (we are not sure which as the labels blew off in the recent gales).

Both types are just starting to flower.

We would be grateful for any advice about what to do, and whether we can save any potatoes.

We have not used any chemicals as we are trying to be organic.

Thank you in advance.

David

[Wicce]

David, it does sound like blight.  You could spray, but if the blight is already visible it's probably too late.  Cut all foliage down to ground level and dispose of it - burn it if possible.  Leave the potatoes in the ground, and hope for the best.  If you've cut the greenery down earlier enough you should be able to get a crop.  Good luck.

[David]

Thanks for that Wicce.  Presently it is raining, and 24 degrees, ideal conditions for the blight it seems.  Our tomatoes are presently not affected, so as soon as possible we will follow your advice.

Many thanks,

David

[Benjamin]

[quote user="Wicce"]David, it does sound like blight.  You could spray, but if the blight is already visible it's probably too late.  Cut all foliage down to ground level and dispose of it - burn it if possible.  Leave the potatoes in the ground, and hope for the best.  If you've cut the greenery down earlier enough you should be able to get a crop.  Good luck.[/quote]

Novice gardener question [geek] I also have potato blight, if the potatoes haven't yet flowered is it worth leaving them in or is it better just to dig them up.

I bought certified seed and I've never grown potatoes before so I thought I would at least be safe for the first year.

[Wicce]

Same reply to you, Benjamin.  Blight spreads like wildfire and to be honest once you have spotted the signs it's best just to cut all foliage back asap.  It also affects tomatoes.  Even if the potatoes haven't flowered yet they have probably formed tubers (depending on whether you planted "earlies" etc, and when you planted them), and those tubers will continue to develop.   If you get it early enough there is a chance of getting a crop, but don't wait!

[andyh4]

Certified seed does not protect you against getting blight, only that the tubers you have bought do not have it in the first place (and other deseases as well).  If they have not flowered yet your  crop is likely to be rather small but Wicce is right, best advice is to remove and destroy the affected tops.  You might get away with removing just the affected stems but frankly with this season's weather I doubt that will help unless we now get a prolonged dry spell - not on my weather monitor unfortunately.

[Quillan]

Oh dear I to have blight and have now planted out my toms about10M away from the potatoes. Can I spray the Toms and what with?

[andyh4]

Bordeaux mixture - copper based fungicide - makes the toms taste funny if you pick them too soon so do read the instructions if you go this route.

[Jazzer]

I have 2 varities of potato- Desiree and Charlotte, both planted in April. So far the Desiree's have flowered but not the Charlottes.  Last week I sprayed with Bordeaux. The leaves are yellowing and I think I must have blight. However today I have dug samples of both and the potatoes appear  to be excellent. Any ideas?

[andyh4]

Most likely blight, which affects leaves and stems first, the tubers rather later.

I have had it where the whole tops have died back, but virtually all of the potatoes were fit to cook and eat - however a few weeks later and the potatoes in store were begining to rot.  So it's a  question of time and using tubers from affected plants quickly because they won't store.