scvirginia said:
Is your mom really black-thumbed, or is she maybe just not motivated because you have the green fingers, and will grow stuff for her? 
Yeah, she's really that black thumbed. She killed countless plants during my childhood by spraying their leaves with Johnson wood wax to make them shinier... and smother them to death. And that's without counting the legion of overwatered victims, cold drafts killing expensive orchids etc.
But now back to raspberries.
NR7 refers to a cultivar of raspberry selected in New Zealand around 1999. It's small, spineless, compact, with an upright habit and, this will no doubt interest you, it has been rejected as a commercial variety due to low yields, short fruiting season and serious troubles with pests following field tests in the US and Canada.
If you want my opinion NR7 is a hit or miss affair with excellent PR backing it. It's not something I would buy, and seems overpriced as well.
There's a smaller cultivar introduced in the 90's called Autumn Bliss which, while larger than NR7, is much much better all around. It will grow about 4ft, thus needing a large container (top tip: a wheeled trolley underneath it does miracles), but it's usually erect and much much less fussy than NR7. If you can find it, get this one.
Joan J is supposed to be an improved Autumn Bliss introduced in 2009, but I have no direct experience with it: it's supposed to be even better yielding and to start fruiting earlier.
Now let's speak of ancillaries. Special potting soils and fertilizers are more often than not gimmicks to push home gardeners into buying stuff they don't want and don't need. Get some nice general purpose soil from a farming supply store and it will do well.
Personally I have much shifted my preference for potted plants towards liquid fertilizers: those available nowadays are excellent products. They can be applied both through irrigation and by foliar spray. If you want the absolutely best stuff available head to the nearest shop selling pot growing supply. No, really: these stores have the top growing supplies and the guys running them are much more knowledgeable than your standard big box store employee.
That would be all for now. Any more questions, you know where to find me.
