David (Normandy) wrote:

snipped

I always have one extreme or the other. Enough courgettes to feed a small
town or none. Usually a few are lost to the end rot so I take care when
watering not to get any on the flowers, but sometimes every plant gets what
I think is some form of mosaic virus and they just stop growing full stop,
plants and courgettes both. Typically if one plant get it they all do even
if the affected plant is pulled up and destroyed.

David.
Both of my plants are outside, in very large tubs and right together.
You would think that a highly contagious plant disease in affecting one
plant would affect the other. But no. One very healthy cropper and one
very sick non-producing plant. The latter does appear to be blossom end
rot in spite of applying calcium once a week and treating with tlc.
Still, as another poster said, the first plant is producing enough crop
to feed an army. And I'm the only one in the house who likes
courgettes.