Correction to my earlier complaint about Cara spuds.
They did get blight and I had thought I had no crop at all. Then I noticed a couple on the surface, half-eaten (by voles probably) On closer inspection, there were plenty there, but not as big as they should have been, of course. Harvested them this afternoon. Yum. Hope they'll keep!
Claire: One or two courgette plants (as you've now discovered) is/are plenty, unless you really like courgettes!