Prolific, heavy producers for a couple of weeks, then nothing. However, if you plant them in succession, you can have them producing all season. Some have had good luck with cutting them back to the second node when production slows/ceases, and they grow and produce another good crop. They do take a lot of space. I had 2/3 of a 4x4 bed filled and they were hard to find, hard to pick. In the future, I'll plant only along the edge of the bed, no deeper than one square.

Granny

Here is a link that might be useful: Annie's Kitchen Garden

Mine never got big, were hard to germinate, and didn't seem to produce much at all. Of course I didn't trim them back at all. I'm going to stick to pole beans. Sorry you had chipmunk problems. Chicken wire may help with that. Ask EG.

Here is a link that might be useful: Sinfonian's garden adventure