Slugs and snails? They can devour Busy Lizzie overnight.

Exactly what I think.

Hi PatK
I didn't see your question, but I have just asked the same. Its also happened to me. They look very sad.:-(

It happened to one of mine over night and just left with the main stalk I put a ring of salt around the other pot base and its not been eaten

There has also been a virus of busy lizzies for the past few years that causes this effect. If this is what has cuased it, the recommendation is not to grow them in the same place next year

Mine have been struggling and very slow to get going but they seem to be picking up a bit now. Last year they were hopeless.