I have ONE raspberry bush. It produces from about mid-June to September. Right now we're getting about a pint every third day. It started as a dying twig three years ago and is now about 6 feet wide by 5 feet high, although the canes are much longer and will trail all over the ground. I would plant fewer than you want, because you'll get a lot more volunteers - they're quite invasive (even if you like them). You might even want to put them in pots to contain their zeal. 7 plants, once they get going, would be enough to run a farm stand if they put out like mine.

Thank you badseed for your comments - I will definitely consider scaling back my plant #s based on your experience. I can always add more at a future date if I don't have the same experience.

Thanks again.