Allotment Gardening Advice Help Chat

Growing => Growing in Greenhouses & Polytunnels => Topic started by: sonnycbr on November 17, 2013, 09:41

Title: Blight??
Post by: sonnycbr on November 17, 2013, 09:41
I planted first early spuds in 12" pots a couple of months ago. When the weather got a bit colder, I moved them into the tunnel. Up until a week ago they were growing well. When I went to look at them yesterday, they look totally dead. The tops are all withered and blackened. I've never had blight before but this certainly looks like it to me.Does blight carry over into winter months? What about growing tomatoes in the tunnel next season? Many thanks.
Title: Re: Blight??
Post by: grendel on November 17, 2013, 09:50
frost?
Grendel
Title: Re: Blight??
Post by: DD. on November 17, 2013, 10:03
Blight is one of the banes of growing spuds for a "seasonal" crop.

Blight carries over in live plant material and it appears you may have carried it into your polytunnel.
Title: Re: Blight??
Post by: brianbishop on November 17, 2013, 10:05
I agree with Grendel. FROST, for blight I believe the temp has to be 11c and humidity 90 for a 12 hour period, don't think we have conditions like that recently.
Bish
Title: Re: Blight??
Post by: DD. on November 17, 2013, 10:20
But in a polytunnel?
Title: Re: Blight??
Post by: JayG on November 17, 2013, 10:21
Frost can blacken potato foliage literally overnight, although in theory the tubers could re-sprout as long as they haven't been frosted too.
Although blight can kill the plants quite quickly you would probably have noticed the dark brown lesions on the leaves a few days before they actually died (but not if you were only able to check them once a week, of course.  :unsure:)

According to the RHS there remains a slight doubt as to exactly how blight overwinters, but having grown them in pots you should be OK as long as you don't use the same compost for growing potatoes or tomatoes in next year.
Title: Re: Blight??
Post by: brianbishop on November 18, 2013, 10:05
DD my max/min thermometer has show 2c in my p/tunnel last week!
Bish