I am planning on growing a couple of small rows of Dragon's Tongue beans before long, and was wondering about something...

These are generally described as bush beans in terms of their growing habit. But the descriptions I see in catalogs make it sound like the plants are bigger and more productive that other bush varieties. Can anyone tell me if these are like most bush varieties, that simply produce once before going dormant?

Right now I have one row full of snow peas on the spot where I want to plant one of my two rows of DT. I am trying to decide if it is a good idea to stagger the planting (and let the snow peas grow a bit longer before taking them out) or if I should just plant all both rows as early as possible so I can get a bigger harvest for the whole season. Around here I have to plant around the first or second week of May, and the plants stop producing around the end of September.