Last year I started pinching off new growth at the end of July. Almost every tomato on the vine ripened before the fall frosts hit. I plan on doing it again this year.
In previous years I had just let them go and always had tons of green tomatoes when the first hard frosts hit. Some people like those little green tomatoes for pickling, but I am not interested.
For those of us with short seasons, I think it makes sense to "nip them in the bud"
