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.
It's a variety of fusarium wilt and comes from bad seed. The bad news
is that it can stay in the soil for years and will affect everything
in the mint family. One needs to be very careful buying basil plants
from garden centers. If they show any brown on the stems, don'f buy
Regards, Dianna (who learned this the hard way)
To reply, please remove "fluff" from my address.
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