Bob, have you checked for slugs and snails? They love wet climates.
They crawl onto the stalk of the plant and start eating, they may crawl up further and eat leaves or the stalks of leaves, but mostly they seem to start right at the bottom of the main stalk damaging it so much that the whole plant wilts and falls over.
If slugs and snail are the problem, you can buy traps or you can bury opened cans of beer so that they fall in. The easiest method to control them is to pick them off the plants when they are active at night.
Small snakes like to eat them.
Ken
Bob wrote: