[The_Atheling]

Hi All
I'm afraid I'm back with a cucumber question again.
Cukes in G/H (Socrates) are growing in a recirculating hydroponic system. They grow normally until part way through cropping and then older leaves start dying off starting between veins. This accelerates up the plant, cropping slows down but new shoots/vines remain vigorous (see pics).
Dying material does not seem to have yellowing areas around it so it doesn't seem to be blight, alternaria or anthracnose. Some cukes have some superficial scarring, but I guess that might be the rough vines/leaves marking them when they are young. GH is fairly well shaded, but I'm not ruling our scorch.
This only seems to happen in the G/H - my Socrates growing in dirt in the P/T have not seen this problem (yet!). I believe that the cukes have slightly different requirements to the toms that are in the same hydro system and that this problem is a nutrient disorder rather disease, although they grow really well for the first part of their lives.
Any/all thoughts/suggestions very welcome.
Richard

[grinling]

I have had this on cucs poly and courg outside. Both plants keep on producing. Mainly noticed after I had missed a couple of fruits need plucking

[Aunt Sally]

Looks like red spider mite to me 

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